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单词 crc method
释义 EncyclopediaSeeCRCMedicalSeeCANCER: (A) Ovarian carcinoma cells and (B) adenocarcinoma of the prostate (orig. mag. ×500)Malignant neoplasia marked by the uncontrolled growth of cells, often with invasion of healthy tissues locally or throughout the body. Cancer is the second leading cause of death in the U.S. after cardiovascular disease. In 2006 the American Cancer Society (ACS) reported that 564,830 Americans died of cancer and that twice that number were newly diagnosed with one form or another of the disease. The most common cancers in the U.S. are lung, breast, colon, prostate, and skin. Because most cancers occur in patients who are 65 or older, the incidence of cancer is expected to increase as the population ages. More than 200 kinds of cancer have been identified. Cancers that arise from epithelial tissues are called carcinomas; from mesenchymal tissues, sarcomas; from glial cells, gliomas; from lymphatic cells, lymphomas; from blood-forming cells, leukemias; from pigmented skin cells, melanomas; from plasma cells, myelomas. Synonym: malignancy (2) See: carcinoma; leukemia; lymphoma; oncogene; sarcoma

Cancer cells have several reproductive advantages over normal cells. They can make proteins that stimulate their own growth or new blood vessels to bring them nourishment. They can produce enzymes that prevent their chromosomes from aging. They can invade the lymphatic system and bloodstream and find places to grow in new tissues (metastasis).

Usually, as cancer cells proliferate, they become increasingly abnormal and require more of the body's metabolic output for their growth and development. Damage caused by their invasion of healthy tissues results in organ malfunction, pain, and, often, death. See: table (Estimated New Cancer Cases and Deaths by Sex, U.S. 2008)

Etiology

Ionizing radiation, ultraviolet light, some viruses, and drugs that damage nucleic acids may initiate the genetic lesions that result in cancers. The best-known and most widespread type of carcinogen exposure, however, is consumption of tobacco. The ACS estimates that one third of the cancer deaths that occur annually in the U.S. are related to nutrition and other lifestyle factors. Some cancers are familial, i.e., genetic; others result from occupational exposures to carcinogens. Ironically, chemotherapeutic drugs used to treat some cancers may damage chromosomes and occasionally cause secondary malignancies.

Symptoms

Symptoms of widespread cancer include pain, malnutrition, weakness, fatigue, bone fractures, and strokelike syndromes. Early warning signs of cancer may be remembered by the mnemonic CAUTION: Change in bowel or bladder habit; A sore that does not heal; Unusual bleeding or discharge; Thickening or mass in the breast or other body parts; Indigestion or difficulty in swallowing; Obvious change in a wart or a mole; Nagging cough or hoarseness. People should seek prompt medical attention if they observe any of these signs.

Diagnosis

The location of a suspected lesion often dictates the means to diagnose cancer: men with urinary symptoms may be screened for prostate cancer with a prostate specific antigen (PSA) test; an alpha-fetoprotein (AFP) test may be used to screen for liver cancer. Several other tumor markers (such as the CA 125 test for ovarian cancer) are used only after a diagnosis has already been made by other means. Endoscopy and radiography are typically used to locate and assess the extent of the disease, but definitive diagnosis still rests on the examination of cytological specimens (such as the Papanicolaou [Pap] test) or the pathological review of biopsy specimens. See: illustration; table (Controversies in Cancer Screening in the General Population)

Screening for cancers can identify some malignancies before they have invaded neighboring tissues or become widespread. The most widely used screening tests include the Pap test for cervical cancer, mammography for breast cancer, prostate specific antigen tests for prostate carcinoma, and occult blood tests and colonoscopy for intestinal cancers.

Treatment

Surgery, chemotherapy, immunotherapy, hormone therapy, radiation therapy, and combined-modality therapies often are effective methods for treating patients with cancer. The specific treatment used depends on the type, stage, and location of the cancer and the patient's general health.

The pain associated with cancer is often severe. Cancer patients may suffer depression and anxiety and have nutritional deficits. Guidelines addressing these issues are readily available, e.g., from the U.S. Department of Health and Human Services' Agency for Health Care Policy and Research. Publications may be obtained by calling 1-800-4-CANCER or from websites such as from the ACS (www.cancer.org). See: chemotherapy.

Patient care

There must be close collaboration among the entire health care team and the patient and family must be encouraged to participate in care . The patient's knowledge of the disease is determined, misinformation corrected, and information supplied about the disease, its progression, its treatment, and expected outcome. Such information should be updated regularly. The patient's and family's coping mechanisms are supported, and verbalization of feelings and fears, esp. with changes in body image, pain and suffering, and dying and death, is encouraged. Participation in local support groups is encouraged for both patients and families.

Assistance is provided with personal hygiene and physical care as needed. Physical care is directed at the maintenance of fluid and electrolyte balance and proper nutrition. Nutrition is a special concern because tumors compete with normal tissues for nutrients and grow at their expense and because the disease or treatments can cause anorexia, altered taste sensations, mouth ulcerations, vomiting, diarrhea, and draining fistulas. Nutritional support includes assessing the patient's status and problems, experimenting to find foods that the patient can tolerate, avoiding highly aromatic foods, and offering frequent small meals of high-calorie, high-nutrient soft foods along with fluids to limit fatigue and to encourage overall intake. Intake of noncaffeinated liquids should be encouraged: 2 quarts per day of juices or other caloric beverages in frequent, small amounts rather than water alone. Elimination is maintained by administering stool softeners as necessary if analgesic drugs result in constipation.

Using careful and gentle handling, the health care professional assists with range-of-motion exercises, encourages ambulation and mobility, and turns and repositions the immobile patient frequently to decrease the deleterious multisystemic effects of immobilization. The patient is made comfortable by correct body alignment, noninvasive measures (such as guided imagery and cutaneous stimulation), and medication (preferably administered on a regular schedule to prevent pain, with additional dosing to relieve breakthrough pain). Emotional assistance includes allaying the patient's fears of helplessness and loss of control; providing hope for remission or long-term survival but avoiding giving false hope; and providing the patient with realistic reassurance about pain control, comfort, and rest. Psychological counseling and antidepressant therapies may be helpful.

Hospice care (at home or in a dedicated center), if needed, is discussed with the patient and family. The goal is to provide good quality of life with minimal discomfort, pain, and restrictions rather than to continue specific therapy. Family members are encouraged to assume an active role in caring for the patient. Communication is fostered between patient and family and other health care providers, and the patient is helped to maintain control and to carry out realistic decisions about issues of life and death.

To provide effective emotional support to the patient and family, health care professionals must understand and cope with their own feelings about terminal illness and death and seek assistance with grieving and in developing a personal philosophy about dying and death. They will then be better able to listen sensitively to patients' concerns, to offer genuine understanding and comfort, and to help patients and family work through their grief.

bladder cancer

A malignancy that arises in the cells of the urinary bladder. In Western nations, most of the cases are transitional cell carcinomas. Common causes include cigarette smoking, occupational exposure to carcinogens, or chronic bladder infection. Symptoms of bladder cancer may include painful urination, bloody urination, or frequent or urgent urination. Depending on the extent of invasion or spread of the tumor, it may be treated with endoscopy, surgery, chemotherapy, or immunotherapy.

bone cancer

Any malignancy of bone tissue. Primary bone tumors (such as osteosarcomas) are rare in adults; they are seen more often in children and adolescents. Secondary or metastatic bone tumors are far more common. Tumors arising in other areas of the body that metastasize to the bones most often spread from organs such as prostate or breast.

breast cancer

See: breast cancer

cervical cancer

A malignant neoplasm of the cervix of the uterus. With an incidence of 15:100,000, it is the third most common cancer of the female reproductive tract and causes 5% of all cancer deaths among women. Although it may occur in younger women, the average age at diagnosis is 54. The disease is insidious, asymptomatic in the early stages, and best treated when recognized at an early stage.

Etiology

Some strains of the human papillomavirus (HPV) are carcinogenic to cervical epithelium. While there are other risk factors (such as tobacco smoking, early age at first intercourse, and having multiple sex partners), HPV is the major factor responsible for the development of this cancer.

Diagnosis

Periodic Pap tests are recommended for all sexually active women. The tests identify cellular changes with 95% accuracy. Dilatation and curettage, punch biopsy, and colposcopy may be done if Pap test findings raise the suspicion of cancer. If abnormal cells are detected, HPV testing is often performed to screen for presence of one of the high risk types of the virus. See: Bethesda System, The; cervical intraepithelial neoplasia; colposcopy; cryosurgery; loop electrode excision procedure; Papanicolaou test

Treatment

Management varies from cryotherapy or laser therapy for low-grade squamous intraepithelial lesions, conization for carcinoma in situ, to hysterectomy for preinvasive cervical cancer in women who are not planning to have children. Stage-related management of invasive cervical carcinoma includes radiation and/or hysterectomy.

Prevention

Vaccination against human papillomavirus virus (HPV).

See: HPV vaccine.

chimney sweeps' cancer

Cancer of the skin of the scrotum due to chronic irritation by coal soot.

colorectal cancer

Abbreviation: CRC
A malignancy of the colon or rectum. It is the second leading cause of cancer deaths in the U.S. At some time during their lives 6% of Americans will be diagnosed with the disease. In 2008 the ACS estimated that 154,000 Americans would be newly diagnosed with colorectal cancer and that it would cause 50,500 deaths.

Etiology

The cancer occurs more often in people with a family history of the disease, those with familial adenomatous polyposis, and in those with inflammatory bowel diseases such as ulcerative colitis. It also occurs more often in people who are obese than in those who are not and in those who consume a high fat, low-fiber diet.

Symptoms

Symptoms may be absent or may include change in the usual pattern of bowel habits, esp. in those over 40; recent onset of constipation, diarrhea, or tenesmus in an older patient; bright red or dark blood in the stool. Laboratory findings may include iron-deficiency anemia or positive fecal occult blood tests.

Diagnosis

Diagnosis may be suggested by findings on digital rectal examination, anoscopy, flexible or rigid sigmoidoscopy, colonoscopy, virtual colonoscopy, or barium enema examination. It is confirmed by biopsy of suspicious lesions. Prevention includes screening of asymptomatic men and women of average risk starting at age 50, annual home fecal occult blood testing (over a three-day period), and colonoscopy every 10 years. During colonoscopy, removal of benign polyps prevents progression to malignant tumors. If polyps are found, colonoscopy should be repeated in 3 to 5 years (depending on the presence of other risk factors). Detection of colorectal cancer at an early stage via colonoscopy offers patients a very high likelihood of cure rate at 5 years. Neither digital rectal examination nor testing of a single stool specimen from the digital exam provides adequate screening. Patients at increased risk for colorectal cancer (those who have had previous colorectal adenomas or resected cancers or a history of ulcerative colitis or of colon cancer in a first-degree relative younger than 60) should undergo screening more frequently and at an earlier age. When colorectal carcinoma is diagnosed, additional tests are conducted to determine the stage of the disease (chest radiographs, CT, MRI, and blood studies, including carcinoembryonic antigen levels, and liver function studies).

Treatment

Surgical resection performed by laparotomy, minimally invasive surgery, microsurgery, or laparoscopy can cure localized colorectal cancer. Whatever procedure is used, the type of surgery depends on the location of the tumor, and the goal of the surgery is removal of the malignant tumor and adjacent tissue and any lymph nodes that may contain cancer cells. Adjuvant therapies may include chemoembolization of blood vessels that feed the primary tumor or metastases; radiation therapy; brachytherapy; chemotherapy; or monoclonal antibody therapy. Carcinoembryonic antigen is helpful in monitoring patients during and following treatment to determine effectiveness and detect recurrence or metasasis.

Patient care

Health care providers should teach patients the importance of colorectal screening and indicate applicable lifestyle modifications (a low-fat diet, maintenance of a normal body mass index). Patients with familial colon cancer syndromes, such as familial adenomatous polyposis, should be counseled about the need for close surveillance by professional gastroenterologists.

Aspirin and other nonsteroidal anti-inflammatory drugs appear to reduce the number of colon polyps, thus decreasing the risk of developing colorectal cancer. Patients interested in such therapy should discuss its potential risks and benefits with their health care providers.

Patients diagnosed with colorectal cancer who undergo surgery need counseling about the operation, the duration of recovery, and, in many cases, the use of a postoperative colostomy . Before surgery, a stomal therapist consults with the surgeon regarding appropriate stoma location, and the abdomen is marked. The therapist answers questions from the patient and family and begins to develop a relationship that will support the patient through postoperative care and teaching. Patient and family are encouraged to access the ACS (800-ACS-2345 or www.cancer.org) for additional information.

Synonym: carcinoma of the colon; colorectal carcinoma

epithelial cancer

Basal cell carcinoma.

epithelial cancer of the ovary

See: ovarian cancer

esophageal cancer

See: esophageal cancer

fallopian tube cancer

A malignancy that begins to grow in the cells that form the inner surfaces of the fallopian tubes, usually an adenocarcinoma. It is the least common form of gynecological cancer.

familial medullary thyroid cancer

Abbreviation: FMTC
A rare, autosomal, dominantly inherited predisposition to medullary carcinoma of the thyroid. The disease is genetically related to the multiple endocrine neoplasia (MEN) syndromes. However, families affected by FMTC rarely develop hyperparathyroid tumors or pheochromocytoma.

gastric cancer

Adenocarcinoma of the stomach. About 50% to 60% of all carcinomas of the stomach occur in the pyloric region. About 20% occur along the lesser curvature; the rest are located in the fundus, particularly along the greater curvature. Although this form of cancer is common throughout the world in people of all races, the incidence of gastric cancer exhibits unexplained geographic, cultural, and gender differences, with the highest incidence in men over 40 and higher mortality in China, Korea, Japan, Taiwan, Iceland, Chile, and Austria.

From 1930 to the 1990s, the incidence of gastric cancer declined from about 38 cases per 100,000 to about 6 cases per 100,000. In 2010, the ACS estimated there would be 21,000 new cases of gastric cancer in the U.S. and 10,570 deaths from this disease. The prognosis for a particular patient depends on the stage of the disease at the time of diagnosis, but overall the 5-year survival rate is about 19%.

Predisposing Causes

Although the cause of gastric cancer is unknown, predisposing factors include a diet rich in pickled or smoked foods, a history of gastric surgery, and a history of infection by Helicobacter pylori. The disease runs in some families; therefore, there may also be a genetic component.

Complications

Malnutrition occurs as a result of impaired eating, the metabolic demands of the growing tumor, or obstruction of the GI tract. Iron deficiency anemia results as the tumor causes ulceration and bleeding. The tumor can interfere with the production of the intrinsic factor needed for vitamin B12 absorption, resulting in pernicious anemia. As the cancer spreads to regional lymph nodes and nearby structures and metastasizes to other structures, related complications occur.

Signs and Symptoms

In the early stages, the patient may occasionally experience pain in the back or in the epigastric or retrosternal areas that is relieved with nonprescription analgesics. As the tumor grows, the patient may notice a vague feeling of fullness, heaviness, and abdominal distention after meals. Depending on the progression of the cancer, the patient may report weight loss due to disturbance of the appetite; nausea; and vomiting. There may be dysphagia and coffee-ground vomitus if the tumor is located in the cardia and slowly bleeds. Weakness and fatigue are common. Because early symptoms include chronic dyspepsia and epigastric discomfort, patients may self-treat with OTC antacids or histamine blockers, delaying prescribed therapies and allowing the cancer to progress.

Palpation of the abdomen may disclose a mass. A skilled examiner may be able to palpate enlarged lymph nodes, esp. in the supraclavicular and axillary regions.

Diagnostic Studies

Gastric cancer is diagnosed by fiber-optic endoscopy with biopsy. Studies to rule out specific organ metastases include endoscopic ultrasonography, computed tomography scans, chest radiographs, liver and bone scans, and liver biopsy.

Treatment

Radical surgery to remove the tumor is possible in more than one third of patients. Even in the patient whose disease is not considered surgically curable, resection may temporarily ease symptoms and improve the patient’s response to chemotherapy and radiation therapy. The nature and extent of the lesion determine the type of surgery. Surgical procedures include gastroduodenostomy, gastrojejunostomy, partial gastric resection, and total gastrectomy. If metastasis has occurred, the omentum and spleen may have to be removed.

Chemotherapy for GI tumors may help control signs and symptoms and prolong survival. Gastric adenocarcinomas respond to several agents, including fluorouracil, carmustine, doxorubicin, and mitomycin. Tumors that express HER2 antigens respond to treatment with trastuzumab (a monoclonal antibody that targets the human epidermal growth factor). Antispasmodics, antacids, and proton pump inhibitors may help relieve GI acidity and reflux symptoms. Antiemetics can control nausea, which intensifies as the tumor grows. Analgesics, sedatives, and tranquilizers are used to control pain and anxiety.

Patient care

Nutritional intake is monitored, and the patient is weighed periodically. The health care provider initiates comprehensive clinical and laboratory investigations, including serial studies as indicated, if these have not already been done. The patient is prepared physically and emotionally for surgery, chemotherapy, or radiotherapy. During hospitalization, all general patient care concerns apply.

Throughout the course of the illness, a high-protein, high-calorie diet with vitamin supplementation helps the patient avoid or recover from weight loss, malnutrition, and anemia, and promote wound healing. Frequent small meals are offered.

To stimulate a poor appetite, antidepressant or steroid drugs may be administered. The patient is instructed in use of all drugs and the expected adverse effects of treatment, as well as in management strategies for these effects.

Radiation therapy may cause nausea, vomiting, local skin damage, malaise, diarrhea, and fatigue. Chemotherapy may cause bone marrow suppression, infection, nausea, vomiting, mouth ulcers, and hair loss. During radiation or chemotherapy, oral intake is encouraged to remove toxic metabolites. Bland fruit juices, ginger ale, or other fluids, and prescribed antiemetics are provided to minimize nausea and vomiting; comfort and reassurance are offered as needed. The patient is advised to report persistent adverse reactions.

The patient is encouraged to follow a normal routine as much as possible after recovery from surgery and during radiation therapy and chemotherapy. He should stop activities that cause excessive fatigue (at least temporarily) and incorporate rest periods. The patient should avoid crowds and people with known infections. Home-health care is provided as necessary. If curative treatment fails, palliative care and psychological support continues, with questions answered honestly but tactfully. Home or in-patient hospice care referrals are suggested as available.

Synonym: stomach cancer

hard cancer

A cylindrical cancer composed of fibrous tissue. Synonym: scirrhous cancer; scirrhous carcinoma

head and neck cancer

Squamous cell carcinoma usually arising in the pharynx, oral cavity, or larynx. Research has shown links between human papillomavirus infection, tobacco smoking, and excessive alcohol use and head and neck cancers.

interval cancer

A cancer whose presence is diagnosed in the time between scheduled screening tests, e.g., a breast cancer that is not detected by regular periodic mammography, professional examination, and self-breast exams.

kidney cancer

Renal cell carcinoma.

latent cancer

A cancer that grows slowly and has no important health effect on the patient.

lip cancer

A squamous cell carcinoma of the lower lip usually seen in men or smokers.

liver cancer

Malignancy of the liver that results either from spread from a primary source or from primary tumor of the liver itself. The former is the more frequent cause. Male sex, hepatitis B or C, cirrhosis, and other liver diseases are predisposing factors. The liver is the most common site of metastatic spread of tumors that disseminate through the bloodstream. The prognosis for survival is from a few months to 1 yr.

Symptoms

The disease may cause severe pain and tenderness; cachexia (loss of weight); and encephalopathy. Jaundice is common. The liver is enlarged, its surface is nodular, and a central depression or umbilications can often be detected.

LUNG CANCER: Lung cancer seen endoscopically. The tumor is bleeding after being biopsied.

lung cancer

The deadliest form of cancer in the U.S., responsible for about 159,000 deaths a year, according to statistics published by the ACS in 2011. The term includes four cell types: squamous cell (epidermoid) carcinoma, adenocarcinoma, large cell (anaplastic) cancer, and small cell (oat cell) cancer. The vast majority are caused by carcinogens in tobacco smoke, including second-hand smoke. Other risks include exposure to carcinogenic industrial and air pollutants (asbestos, uranium, arsenic, nickel, chromium, iron oxides, coal dust and radioactive dusts), radon gas concentrations, and familial susceptibility. Survival after diagnosis is poor: only one of seven patients lives for 5 years. However, if detected early (before spreading from the lungs), survival rates rise for most people. Radiofrequency ablation (RFA) is a promising therapy for patients with small lung tumors. Synonym: bronchogenic carcinoma See: illustration

Treatment

Treatment includes lung surgery, radiation therapy, and chemotherapy usually in combination.

Patient care

Staging determines the extent of the disease and aids in planning treatment and predicting the prognosis. Lung cancer is relatively difficult to cure but much easier to prevent. Children and adolescents should be discouraged from smoking tobacco products, and current smokers should be assisted in their efforts to quit, e.g., through referrals to local branches of the ACS, smoking-cessation programs, individual counseling, or group therapy.

Screening and Public Health

Chest x-rays do not show small, early cancers, but CT scanning can be used to screen people who have a long history of smoking and who are 50 to 60 years old. In this high-risk group, screening detects the disease in its early stages when it is most likely to be curable. However, since screening is very expensive, and since there are millions of smokers, the public health costs of mass screening are high compared with the cost of encouraging smokers to quit or of teaching teenagers not to start smoking.

oral cavity cancer

Squamous cell carcinoma of the mouth or tongue. Oral cavity cancers are only rarely caused by salivary gland tumors or sarcomas.

ovarian cancer

Any malignant growth in an ovary. About 85% to 90% of ovarian cancers arise from the surface epithelium of the ovary. In the U.S. in 2008, the ACS estimated there would be about 21,600 new patients diagnosed with ovarian cancer and about 15,200 deaths from the disease. Most cases (70%) are diagnosed when the disease is already at an advanced stage because early detection methods are still unsatisfactory. The early symptoms of the disease are often nonspecific and often mimic irritable bowel (constipation, vague abdominal pain, bloating). Initial laboratory studies (routine blood tests and x-rays) are often unremarkable.

Currently, more women die of epithelial ovarian cancer than of all other gynecological cancers combined. A small percentage of patients with ovarian cancer may have a hereditary predisposition, e.g., they have BRCA-1 or BRCA-2 genes. High-risk women include those with multiple first-degree relatives (mother, sister, daughter) or second-degree relatives (aunt, grandmother, cousin) with histories of breast or ovarian cancer. Preventive surgery to remove the ovaries and fallopian tubes is the only way such women can significantly reduce their risk.

Patient care

Ovarian cancer patients may feel threatened or vulnerable. They benefit from pretreatment support and education. Health care professionals address the patient's psychosocial needs while preparing her for treatment and manage the potential adverse reactions and the treatment and changes related to advancing disease.

The first step in care is typically surgical debulking of the tumor. In this phase of care, the surgical oncologist attempts to remove not only the primary tumor, but also as many small tumorlets found within the peritoneum. The patient and family should be taught about the extensive surgical procedure and what to expect after surgery. After surgery, the patient is monitored for infection, circulatory complications, fluid and electrolyte imbalances, and pain. The patient who is to receive chemotherapy should be taught about major adverse reactions to the usual medications employed, taxanes and platinum-based drugs, such as fatigue, nausea and vomiting, hair loss, diarrhea, constipation, mucositis, neuropathy, arthralgia and myalgia, difficulty concentrating (chemobrain), and myelosuppression, as well as about measures to be taken to prevent and manage these problems. Chemotherapy may be given directly into the peritoneum or intravenously. Depression, anger, frustration, and anxiety are common.

After the acute phase of treatment, the patient may undergo premature menopause; loss of fertility; alterations in body image, sexual function, and family relationships; impaired functional capacity; financial difficulties; and loss of spiritual well-being. The patient should be assessed for mood changes, inability to concentrate, fatigue, insomnia, and other symptoms of depression. Her medical history, current medications and treatments, nutritional status, pain rating, elimination pattern, and sexual history should be reviewed for factors that contribute to depression. Participating in a support group, meeting with mental health professionals, and taking an antidepressant or anti-anxiety medication can help alleviate depression and anxiety.

Advancing or relapsing ovarian cancer may cause complications. These may include development of ascites, intestinal obstruction, deep vein thrombosis, malnutrition and cachexia, lymphedema, and pleural effusion. Current five-year survival rates for ovarian cancer are about 30% to 40%. If ovarian cancer recurs after treatment or fails to regress with treatment, palliative and end-of-life care may aid both patients and their families.

cancer of the pancreas

Pancreatic cancer.

pancreatic cancer

Carcinoma of the pancreas. The American Cancer Society estimated there would be 37,700 new cases of the disease in the U.S. in 2008, with 34,300 deaths caused by the illness that year. Although the causes of pancreatic cancer are unknown, it has been found in more men than women, more blacks than whites, more smokers than nonsmokers, and more patients with a history of chronic pancreatitis and diabetes mellitus than without. When cancer occurs in the head of the pancreas, where it may obstruct the bile ducts and cause jaundice, the disease is most likely to be diagnosed at an early stage, when it may be most responsive to therapy. Surgical excision of the tumor and treatment with chemotherapy or radiotherapy may prolong survival in some patients. Only 4% of victims of pancreatic cancer survive 5 years. Synonym: carcinoma of the pancreas; cancer of the pancreaspancreatic carcinoma

primary cancer

The original cell or tissue type from which a metastatic cancer arises.

prostate cancer

See: prostate cancer

scirrhous cancer

Hard cancer.

skin cancer

A broad term that includes basal cell carcinomas, squamous cell carcinomas, and melanomas. Together, these skin cancers are the most common cancers in the U.S. They are all associated with excessive exposure to ultraviolet light, e.g., sun exposure. See: basal cell carcinoma; squamous cell carcinoma; melanoma

Patient care

According to the U.S. Preventative Services Task Force (USPSTF), benefits from routine screening for skin cancers with a total body skin examination are unproven, even in high-risk patients.

stomach cancer

Gastric cancer.

terminal cancer

Widespread or advanced cancer, from which recovery is not expected.

testicular cancer, germ-cell

Any of a group of testicular cancers that include choriocarcinomas, embryonal carcinomas, seminomas, spermatocytic seminomas, sex cord tumors, teratomas, and tumors with mixtures of several different malignant cell types.

cancer of unknown primary site

Disseminated cancer in which the original tissue type is uncertain. Such cancers generally have poor prognoses.

Etiology

Patients with such cancers are usually evaluated for tumors that might respond well to therapy, such as a lymphoma, a thyroid cancer, a germ cell tumor, or neoplasms of the breast or prostate.

cancer of uterus

A malignant neoplasm of the uterus, usually of the endometrium, found most often in women over 50. Other uterine cancers include those that arise in the muscular wall of the uterus (sarcomas), cervical cancers, and trophoblastic cancers. Symptoms may include post menopausal bleeding, bleeding between periods, and irregular, long, heavy periods. Pain during urination and during intercourse may be reported. Diagnosis of endometrial cancer is made by endometrial biopsy. The most common treatment is hysterectomy, although radiation and hormone therapy may be used. See: Bethesda System, The; cervical cancer; cervical intraepithelial neoplasia

vulvar cancer

Any malignant neoplasm of the vulva. Of these, 90% are squamous cell carcinomas; the rest are caused by adenocarcinomas, sarcomas, or Paget's disease.

Vulvar cancer accounts for 4% of all gynecological malignancies. More than 50% of cases occur in postmenopausal women between 65 and 70. Generally, vulvar cancers are localized, slow-growing, and marked by late metastasis to the regional lymph nodes. Treatment may include surgery and/or radiation therapy. See: vulvectomy

*Excludes basal and squamous cell skin cancers and in situ carcinomas except urinary bladder. Carcinoma in situ of the breast accounts for about 67,770 new cases annually, and melanoma in situ accounts for about 54,020 new cases annually. Estimates of new cases are based on incidence rates from the NCI SEER program, 1995 to 2004. SOURCE: ©2008, American Cancer Society, Inc., Surveillance Research
Estimated New CasesEstimated Deaths
MaleFemaleMaleFemale
All sites745,180692,000294,120271,530
Oral cavity & pharynx25,31010,0005,2102,380
Esophagus12,9703,50011,2503,030
Stomach13,1908,3106,4504,430
Colon & rectum77,25071,56024,26025,700
Liver & intrahepatic bile duct15,1906,18012,5705,840
Pancreas18,77018,91017,50016,790
Lung & bronchus114,690100,33090,81071,030
Melanoma-skin34,95027,5305,4003,020
Breast1,990182,46045040,480
Uterine corpus40,1007,470
Ovary21,65015,520
Prostate186,32028,660
Urinary bladder21,23017,5809,9504,150
Kidney & renal pelvis33,13021,2608,1004,910
Brain & other nervous system11,78010,0307,4205,650
Thyroid8,93028,410680910
Non-Hodgkin lymphoma35,45030,6709,7909,370
Leukemia25,18019,09012,4609,250
*Note: Cancer screening tests are most likely to be useful when: (1) the cancer is common and deadly; (2) the test reliably distinguishes between healthy and diseased people; (3) early detection of the disease leads to improved treatments; (4) treatments are safe and well-tolerated; (5) the psychological effects of test results are addressed sensitively and carefully; (6) the tests are applied to people who will truly benefit from them.
TestTo DetectDiscussion
Breast self-examinationBreast cancerMonthly self-examination by women is a noninvasive way to screen for changes in the breast. This method detects many benign and cancerous lumps, but its ability to prolong life is still debated.
MammographyBreast cancerMammography is clearly effective screening in women over 50. Most mammograms are obtained by women in their 40s. The incidence of cancer is higher in later life, when mammography use tends to decline.
Digital rectal examination (DRE)Colorectal cancer, prostate cancerDRE is easy to perform and inexpensive but its cancer screening value is unproven; and, when it detects cancers, there is no proof that the test results in better patient outcomes. In addition, DRE detects a very small number of cancers, only those within the reach of the examiner.
Fecal occult blood testColorectal cancerIn people over 50, testing stool specimens for hidden bleeding detects many cancers; this detection results in earlier treatment and prolongation of life. The accuracy and value of the test relative to sigmoidoscopy and colonoscopy are uncertain.
Chest x-ray, sputum cytology, CT of the chestLung cancerProspective studies have yielded conflicting results for any method of screening for lung cancer in smokers, and the costs of screening, e.g., with computed tomography of the chest, may be prohibitive. The tests are of no value to nonsmokers.
Prostate specific antigen (PSA)Prostate cancerPSA testing detects many previously undetected prostate cancers but may result in increased death and disease due to complications from subsequent surgery. Refinements in its application may improve its usefulness as a screening tool.
Genetic testingFor predisposition to a variety of cancersThe predictive value of genetic testing for cancer is very small. Experts are debating the emotional and ethical consequences of genetic cancer screening tests.

colorectal cancer

Abbreviation: CRC
A malignancy of the colon or rectum. It is the second leading cause of cancer deaths in the U.S. At some time during their lives 6% of Americans will be diagnosed with the disease. In 2008 the ACS estimated that 154,000 Americans would be newly diagnosed with colorectal cancer and that it would cause 50,500 deaths.

Etiology

The cancer occurs more often in people with a family history of the disease, those with familial adenomatous polyposis, and in those with inflammatory bowel diseases such as ulcerative colitis. It also occurs more often in people who are obese than in those who are not and in those who consume a high fat, low-fiber diet.

Symptoms

Symptoms may be absent or may include change in the usual pattern of bowel habits, esp. in those over 40; recent onset of constipation, diarrhea, or tenesmus in an older patient; bright red or dark blood in the stool. Laboratory findings may include iron-deficiency anemia or positive fecal occult blood tests.

Diagnosis

Diagnosis may be suggested by findings on digital rectal examination, anoscopy, flexible or rigid sigmoidoscopy, colonoscopy, virtual colonoscopy, or barium enema examination. It is confirmed by biopsy of suspicious lesions. Prevention includes screening of asymptomatic men and women of average risk starting at age 50, annual home fecal occult blood testing (over a three-day period), and colonoscopy every 10 years. During colonoscopy, removal of benign polyps prevents progression to malignant tumors. If polyps are found, colonoscopy should be repeated in 3 to 5 years (depending on the presence of other risk factors). Detection of colorectal cancer at an early stage via colonoscopy offers patients a very high likelihood of cure rate at 5 years. Neither digital rectal examination nor testing of a single stool specimen from the digital exam provides adequate screening. Patients at increased risk for colorectal cancer (those who have had previous colorectal adenomas or resected cancers or a history of ulcerative colitis or of colon cancer in a first-degree relative younger than 60) should undergo screening more frequently and at an earlier age. When colorectal carcinoma is diagnosed, additional tests are conducted to determine the stage of the disease (chest radiographs, CT, MRI, and blood studies, including carcinoembryonic antigen levels, and liver function studies).

Treatment

Surgical resection performed by laparotomy, minimally invasive surgery, microsurgery, or laparoscopy can cure localized colorectal cancer. Whatever procedure is used, the type of surgery depends on the location of the tumor, and the goal of the surgery is removal of the malignant tumor and adjacent tissue and any lymph nodes that may contain cancer cells. Adjuvant therapies may include chemoembolization of blood vessels that feed the primary tumor or metastases; radiation therapy; brachytherapy; chemotherapy; or monoclonal antibody therapy. Carcinoembryonic antigen is helpful in monitoring patients during and following treatment to determine effectiveness and detect recurrence or metasasis.

Patient care

Health care providers should teach patients the importance of colorectal screening and indicate applicable lifestyle modifications (a low-fat diet, maintenance of a normal body mass index). Patients with familial colon cancer syndromes, such as familial adenomatous polyposis, should be counseled about the need for close surveillance by professional gastroenterologists.

Aspirin and other nonsteroidal anti-inflammatory drugs appear to reduce the number of colon polyps, thus decreasing the risk of developing colorectal cancer. Patients interested in such therapy should discuss its potential risks and benefits with their health care providers.

Patients diagnosed with colorectal cancer who undergo surgery need counseling about the operation, the duration of recovery, and, in many cases, the use of a postoperative colostomy . Before surgery, a stomal therapist consults with the surgeon regarding appropriate stoma location, and the abdomen is marked. The therapist answers questions from the patient and family and begins to develop a relationship that will support the patient through postoperative care and teaching. Patient and family are encouraged to access the ACS (800-ACS-2345 or www.cancer.org) for additional information.

Synonym: carcinoma of the colon; colorectal carcinomaSee also: cancer">CRC of the prostate (orig. mag. ×500)" href="javascript:eml2('davisTab', 'c04.jpg')">CANCER: (A) Ovarian carcinoma cells and (B) adenocarcinoma of the prostate (orig. mag. ×500)Malignant neoplasia marked by the uncontrolled growth of cells, often with invasion of healthy tissues locally or throughout the body. Cancer is the second leading cause of death in the U.S. after cardiovascular disease. In 2006 the American Cancer Society (ACS) reported that 564,830 Americans died of cancer and that twice that number were newly diagnosed with one form or another of the disease. The most common cancers in the U.S. are lung, breast, colon, prostate, and skin. Because most cancers occur in patients who are 65 or older, the incidence of cancer is expected to increase as the population ages. More than 200 kinds of cancer have been identified. Cancers that arise from epithelial tissues are called carcinomas; from mesenchymal tissues, sarcomas; from glial cells, gliomas; from lymphatic cells, lymphomas; from blood-forming cells, leukemias; from pigmented skin cells, melanomas; from plasma cells, myelomas. Synonym: malignancy (2) See: carcinoma; leukemia; lymphoma; oncogene; sarcoma

Cancer cells have several reproductive advantages over normal cells. They can make proteins that stimulate their own growth or new blood vessels to bring them nourishment. They can produce enzymes that prevent their chromosomes from aging. They can invade the lymphatic system and bloodstream and find places to grow in new tissues (metastasis).

Usually, as cancer cells proliferate, they become increasingly abnormal and require more of the body's metabolic output for their growth and development. Damage caused by their invasion of healthy tissues results in organ malfunction, pain, and, often, death. See: table (Estimated New Cancer Cases and Deaths by Sex, U.S. 2008)

Etiology

Ionizing radiation, ultraviolet light, some viruses, and drugs that damage nucleic acids may initiate the genetic lesions that result in cancers. The best-known and most widespread type of carcinogen exposure, however, is consumption of tobacco. The ACS estimates that one third of the cancer deaths that occur annually in the U.S. are related to nutrition and other lifestyle factors. Some cancers are familial, i.e., genetic; others result from occupational exposures to carcinogens. Ironically, chemotherapeutic drugs used to treat some cancers may damage chromosomes and occasionally cause secondary malignancies.

Symptoms

Symptoms of widespread cancer include pain, malnutrition, weakness, fatigue, bone fractures, and strokelike syndromes. Early warning signs of cancer may be remembered by the mnemonic CAUTION: Change in bowel or bladder habit; A sore that does not heal; Unusual bleeding or discharge; Thickening or mass in the breast or other body parts; Indigestion or difficulty in swallowing; Obvious change in a wart or a mole; Nagging cough or hoarseness. People should seek prompt medical attention if they observe any of these signs.

Diagnosis

The location of a suspected lesion often dictates the means to diagnose cancer: men with urinary symptoms may be screened for prostate cancer with a prostate specific antigen (PSA) test; an alpha-fetoprotein (AFP) test may be used to screen for liver cancer. Several other tumor markers (such as the CA 125 test for ovarian cancer) are used only after a diagnosis has already been made by other means. Endoscopy and radiography are typically used to locate and assess the extent of the disease, but definitive diagnosis still rests on the examination of cytological specimens (such as the Papanicolaou [Pap] test) or the pathological review of biopsy specimens. See: illustration; table (Controversies in Cancer Screening in the General Population)

Screening for cancers can identify some malignancies before they have invaded neighboring tissues or become widespread. The most widely used screening tests include the Pap test for cervical cancer, mammography for breast cancer, prostate specific antigen tests for prostate carcinoma, and occult blood tests and colonoscopy for intestinal cancers.

Treatment

Surgery, chemotherapy, immunotherapy, hormone therapy, radiation therapy, and combined-modality therapies often are effective methods for treating patients with cancer. The specific treatment used depends on the type, stage, and location of the cancer and the patient's general health.

The pain associated with cancer is often severe. Cancer patients may suffer depression and anxiety and have nutritional deficits. Guidelines addressing these issues are readily available, e.g., from the U.S. Department of Health and Human Services' Agency for Health Care Policy and Research. Publications may be obtained by calling 1-800-4-CANCER or from websites such as from the ACS (www.cancer.org). See: chemotherapy.

Patient care

There must be close collaboration among the entire health care team and the patient and family must be encouraged to participate in care . The patient's knowledge of the disease is determined, misinformation corrected, and information supplied about the disease, its progression, its treatment, and expected outcome. Such information should be updated regularly. The patient's and family's coping mechanisms are supported, and verbalization of feelings and fears, esp. with changes in body image, pain and suffering, and dying and death, is encouraged. Participation in local support groups is encouraged for both patients and families.

Assistance is provided with personal hygiene and physical care as needed. Physical care is directed at the maintenance of fluid and electrolyte balance and proper nutrition. Nutrition is a special concern because tumors compete with normal tissues for nutrients and grow at their expense and because the disease or treatments can cause anorexia, altered taste sensations, mouth ulcerations, vomiting, diarrhea, and draining fistulas. Nutritional support includes assessing the patient's status and problems, experimenting to find foods that the patient can tolerate, avoiding highly aromatic foods, and offering frequent small meals of high-calorie, high-nutrient soft foods along with fluids to limit fatigue and to encourage overall intake. Intake of noncaffeinated liquids should be encouraged: 2 quarts per day of juices or other caloric beverages in frequent, small amounts rather than water alone. Elimination is maintained by administering stool softeners as necessary if analgesic drugs result in constipation.

Using careful and gentle handling, the health care professional assists with range-of-motion exercises, encourages ambulation and mobility, and turns and repositions the immobile patient frequently to decrease the deleterious multisystemic effects of immobilization. The patient is made comfortable by correct body alignment, noninvasive measures (such as guided imagery and cutaneous stimulation), and medication (preferably administered on a regular schedule to prevent pain, with additional dosing to relieve breakthrough pain). Emotional assistance includes allaying the patient's fears of helplessness and loss of control; providing hope for remission or long-term survival but avoiding giving false hope; and providing the patient with realistic reassurance about pain control, comfort, and rest. Psychological counseling and antidepressant therapies may be helpful.

Hospice care (at home or in a dedicated center), if needed, is discussed with the patient and family. The goal is to provide good quality of life with minimal discomfort, pain, and restrictions rather than to continue specific therapy. Family members are encouraged to assume an active role in caring for the patient. Communication is fostered between patient and family and other health care providers, and the patient is helped to maintain control and to carry out realistic decisions about issues of life and death.

To provide effective emotional support to the patient and family, health care professionals must understand and cope with their own feelings about terminal illness and death and seek assistance with grieving and in developing a personal philosophy about dying and death. They will then be better able to listen sensitively to patients' concerns, to offer genuine understanding and comfort, and to help patients and family work through their grief.

bladder cancer

A malignancy that arises in the cells of the urinary bladder. In Western nations, most of the cases are transitional cell carcinomas. Common causes include cigarette smoking, occupational exposure to carcinogens, or chronic bladder infection. Symptoms of bladder cancer may include painful urination, bloody urination, or frequent or urgent urination. Depending on the extent of invasion or spread of the tumor, it may be treated with endoscopy, surgery, chemotherapy, or immunotherapy.

bone cancer

Any malignancy of bone tissue. Primary bone tumors (such as osteosarcomas) are rare in adults; they are seen more often in children and adolescents. Secondary or metastatic bone tumors are far more common. Tumors arising in other areas of the body that metastasize to the bones most often spread from organs such as prostate or breast.

breast cancer

See: breast cancer

cervical cancer

A malignant neoplasm of the cervix of the uterus. With an incidence of 15:100,000, it is the third most common cancer of the female reproductive tract and causes 5% of all cancer deaths among women. Although it may occur in younger women, the average age at diagnosis is 54. The disease is insidious, asymptomatic in the early stages, and best treated when recognized at an early stage.

Etiology

Some strains of the human papillomavirus (HPV) are carcinogenic to cervical epithelium. While there are other risk factors (such as tobacco smoking, early age at first intercourse, and having multiple sex partners), HPV is the major factor responsible for the development of this cancer.

Diagnosis

Periodic Pap tests are recommended for all sexually active women. The tests identify cellular changes with 95% accuracy. Dilatation and curettage, punch biopsy, and colposcopy may be done if Pap test findings raise the suspicion of cancer. If abnormal cells are detected, HPV testing is often performed to screen for presence of one of the high risk types of the virus. See: Bethesda System, The; cervical intraepithelial neoplasia; colposcopy; cryosurgery; loop electrode excision procedure; Papanicolaou test

Treatment

Management varies from cryotherapy or laser therapy for low-grade squamous intraepithelial lesions, conization for carcinoma in situ, to hysterectomy for preinvasive cervical cancer in women who are not planning to have children. Stage-related management of invasive cervical carcinoma includes radiation and/or hysterectomy.

Prevention

Vaccination against human papillomavirus virus (HPV).

See: HPV vaccine.

chimney sweeps' cancer

Cancer of the skin of the scrotum due to chronic irritation by coal soot.

colorectal cancer

Abbreviation: CRC
A malignancy of the colon or rectum. It is the second leading cause of cancer deaths in the U.S. At some time during their lives 6% of Americans will be diagnosed with the disease. In 2008 the ACS estimated that 154,000 Americans would be newly diagnosed with colorectal cancer and that it would cause 50,500 deaths.

Etiology

The cancer occurs more often in people with a family history of the disease, those with familial adenomatous polyposis, and in those with inflammatory bowel diseases such as ulcerative colitis. It also occurs more often in people who are obese than in those who are not and in those who consume a high fat, low-fiber diet.

Symptoms

Symptoms may be absent or may include change in the usual pattern of bowel habits, esp. in those over 40; recent onset of constipation, diarrhea, or tenesmus in an older patient; bright red or dark blood in the stool. Laboratory findings may include iron-deficiency anemia or positive fecal occult blood tests.

Diagnosis

Diagnosis may be suggested by findings on digital rectal examination, anoscopy, flexible or rigid sigmoidoscopy, colonoscopy, virtual colonoscopy, or barium enema examination. It is confirmed by biopsy of suspicious lesions. Prevention includes screening of asymptomatic men and women of average risk starting at age 50, annual home fecal occult blood testing (over a three-day period), and colonoscopy every 10 years. During colonoscopy, removal of benign polyps prevents progression to malignant tumors. If polyps are found, colonoscopy should be repeated in 3 to 5 years (depending on the presence of other risk factors). Detection of colorectal cancer at an early stage via colonoscopy offers patients a very high likelihood of cure rate at 5 years. Neither digital rectal examination nor testing of a single stool specimen from the digital exam provides adequate screening. Patients at increased risk for colorectal cancer (those who have had previous colorectal adenomas or resected cancers or a history of ulcerative colitis or of colon cancer in a first-degree relative younger than 60) should undergo screening more frequently and at an earlier age. When colorectal carcinoma is diagnosed, additional tests are conducted to determine the stage of the disease (chest radiographs, CT, MRI, and blood studies, including carcinoembryonic antigen levels, and liver function studies).

Treatment

Surgical resection performed by laparotomy, minimally invasive surgery, microsurgery, or laparoscopy can cure localized colorectal cancer. Whatever procedure is used, the type of surgery depends on the location of the tumor, and the goal of the surgery is removal of the malignant tumor and adjacent tissue and any lymph nodes that may contain cancer cells. Adjuvant therapies may include chemoembolization of blood vessels that feed the primary tumor or metastases; radiation therapy; brachytherapy; chemotherapy; or monoclonal antibody therapy. Carcinoembryonic antigen is helpful in monitoring patients during and following treatment to determine effectiveness and detect recurrence or metasasis.

Patient care

Health care providers should teach patients the importance of colorectal screening and indicate applicable lifestyle modifications (a low-fat diet, maintenance of a normal body mass index). Patients with familial colon cancer syndromes, such as familial adenomatous polyposis, should be counseled about the need for close surveillance by professional gastroenterologists.

Aspirin and other nonsteroidal anti-inflammatory drugs appear to reduce the number of colon polyps, thus decreasing the risk of developing colorectal cancer. Patients interested in such therapy should discuss its potential risks and benefits with their health care providers.

Patients diagnosed with colorectal cancer who undergo surgery need counseling about the operation, the duration of recovery, and, in many cases, the use of a postoperative colostomy . Before surgery, a stomal therapist consults with the surgeon regarding appropriate stoma location, and the abdomen is marked. The therapist answers questions from the patient and family and begins to develop a relationship that will support the patient through postoperative care and teaching. Patient and family are encouraged to access the ACS (800-ACS-2345 or www.cancer.org) for additional information.

Synonym: carcinoma of the colon; colorectal carcinoma

epithelial cancer

Basal cell carcinoma.

epithelial cancer of the ovary

See: ovarian cancer

esophageal cancer

See: esophageal cancer

fallopian tube cancer

A malignancy that begins to grow in the cells that form the inner surfaces of the fallopian tubes, usually an adenocarcinoma. It is the least common form of gynecological cancer.

familial medullary thyroid cancer

Abbreviation: FMTC
A rare, autosomal, dominantly inherited predisposition to medullary carcinoma of the thyroid. The disease is genetically related to the multiple endocrine neoplasia (MEN) syndromes. However, families affected by FMTC rarely develop hyperparathyroid tumors or pheochromocytoma.

gastric cancer

Adenocarcinoma of the stomach. About 50% to 60% of all carcinomas of the stomach occur in the pyloric region. About 20% occur along the lesser curvature; the rest are located in the fundus, particularly along the greater curvature. Although this form of cancer is common throughout the world in people of all races, the incidence of gastric cancer exhibits unexplained geographic, cultural, and gender differences, with the highest incidence in men over 40 and higher mortality in China, Korea, Japan, Taiwan, Iceland, Chile, and Austria.

From 1930 to the 1990s, the incidence of gastric cancer declined from about 38 cases per 100,000 to about 6 cases per 100,000. In 2010, the ACS estimated there would be 21,000 new cases of gastric cancer in the U.S. and 10,570 deaths from this disease. The prognosis for a particular patient depends on the stage of the disease at the time of diagnosis, but overall the 5-year survival rate is about 19%.

Predisposing Causes

Although the cause of gastric cancer is unknown, predisposing factors include a diet rich in pickled or smoked foods, a history of gastric surgery, and a history of infection by Helicobacter pylori. The disease runs in some families; therefore, there may also be a genetic component.

Complications

Malnutrition occurs as a result of impaired eating, the metabolic demands of the growing tumor, or obstruction of the GI tract. Iron deficiency anemia results as the tumor causes ulceration and bleeding. The tumor can interfere with the production of the intrinsic factor needed for vitamin B12 absorption, resulting in pernicious anemia. As the cancer spreads to regional lymph nodes and nearby structures and metastasizes to other structures, related complications occur.

Signs and Symptoms

In the early stages, the patient may occasionally experience pain in the back or in the epigastric or retrosternal areas that is relieved with nonprescription analgesics. As the tumor grows, the patient may notice a vague feeling of fullness, heaviness, and abdominal distention after meals. Depending on the progression of the cancer, the patient may report weight loss due to disturbance of the appetite; nausea; and vomiting. There may be dysphagia and coffee-ground vomitus if the tumor is located in the cardia and slowly bleeds. Weakness and fatigue are common. Because early symptoms include chronic dyspepsia and epigastric discomfort, patients may self-treat with OTC antacids or histamine blockers, delaying prescribed therapies and allowing the cancer to progress.

Palpation of the abdomen may disclose a mass. A skilled examiner may be able to palpate enlarged lymph nodes, esp. in the supraclavicular and axillary regions.

Diagnostic Studies

Gastric cancer is diagnosed by fiber-optic endoscopy with biopsy. Studies to rule out specific organ metastases include endoscopic ultrasonography, computed tomography scans, chest radiographs, liver and bone scans, and liver biopsy.

Treatment

Radical surgery to remove the tumor is possible in more than one third of patients. Even in the patient whose disease is not considered surgically curable, resection may temporarily ease symptoms and improve the patient’s response to chemotherapy and radiation therapy. The nature and extent of the lesion determine the type of surgery. Surgical procedures include gastroduodenostomy, gastrojejunostomy, partial gastric resection, and total gastrectomy. If metastasis has occurred, the omentum and spleen may have to be removed.

Chemotherapy for GI tumors may help control signs and symptoms and prolong survival. Gastric adenocarcinomas respond to several agents, including fluorouracil, carmustine, doxorubicin, and mitomycin. Tumors that express HER2 antigens respond to treatment with trastuzumab (a monoclonal antibody that targets the human epidermal growth factor). Antispasmodics, antacids, and proton pump inhibitors may help relieve GI acidity and reflux symptoms. Antiemetics can control nausea, which intensifies as the tumor grows. Analgesics, sedatives, and tranquilizers are used to control pain and anxiety.

Patient care

Nutritional intake is monitored, and the patient is weighed periodically. The health care provider initiates comprehensive clinical and laboratory investigations, including serial studies as indicated, if these have not already been done. The patient is prepared physically and emotionally for surgery, chemotherapy, or radiotherapy. During hospitalization, all general patient care concerns apply.

Throughout the course of the illness, a high-protein, high-calorie diet with vitamin supplementation helps the patient avoid or recover from weight loss, malnutrition, and anemia, and promote wound healing. Frequent small meals are offered.

To stimulate a poor appetite, antidepressant or steroid drugs may be administered. The patient is instructed in use of all drugs and the expected adverse effects of treatment, as well as in management strategies for these effects.

Radiation therapy may cause nausea, vomiting, local skin damage, malaise, diarrhea, and fatigue. Chemotherapy may cause bone marrow suppression, infection, nausea, vomiting, mouth ulcers, and hair loss. During radiation or chemotherapy, oral intake is encouraged to remove toxic metabolites. Bland fruit juices, ginger ale, or other fluids, and prescribed antiemetics are provided to minimize nausea and vomiting; comfort and reassurance are offered as needed. The patient is advised to report persistent adverse reactions.

The patient is encouraged to follow a normal routine as much as possible after recovery from surgery and during radiation therapy and chemotherapy. He should stop activities that cause excessive fatigue (at least temporarily) and incorporate rest periods. The patient should avoid crowds and people with known infections. Home-health care is provided as necessary. If curative treatment fails, palliative care and psychological support continues, with questions answered honestly but tactfully. Home or in-patient hospice care referrals are suggested as available.

Synonym: stomach cancer

hard cancer

A cylindrical cancer composed of fibrous tissue. Synonym: scirrhous cancer; scirrhous carcinoma

head and neck cancer

Squamous cell carcinoma usually arising in the pharynx, oral cavity, or larynx. Research has shown links between human papillomavirus infection, tobacco smoking, and excessive alcohol use and head and neck cancers.

interval cancer

A cancer whose presence is diagnosed in the time between scheduled screening tests, e.g., a breast cancer that is not detected by regular periodic mammography, professional examination, and self-breast exams.

kidney cancer

Renal cell carcinoma.

latent cancer

A cancer that grows slowly and has no important health effect on the patient.

lip cancer

A squamous cell carcinoma of the lower lip usually seen in men or smokers.

liver cancer

Malignancy of the liver that results either from spread from a primary source or from primary tumor of the liver itself. The former is the more frequent cause. Male sex, hepatitis B or C, cirrhosis, and other liver diseases are predisposing factors. The liver is the most common site of metastatic spread of tumors that disseminate through the bloodstream. The prognosis for survival is from a few months to 1 yr.

Symptoms

The disease may cause severe pain and tenderness; cachexia (loss of weight); and encephalopathy. Jaundice is common. The liver is enlarged, its surface is nodular, and a central depression or umbilications can often be detected.

LUNG CANCER: Lung cancer seen endoscopically. The tumor is bleeding after being biopsied.

lung cancer

The deadliest form of cancer in the U.S., responsible for about 159,000 deaths a year, according to statistics published by the ACS in 2011. The term includes four cell types: squamous cell (epidermoid) carcinoma, adenocarcinoma, large cell (anaplastic) cancer, and small cell (oat cell) cancer. The vast majority are caused by carcinogens in tobacco smoke, including second-hand smoke. Other risks include exposure to carcinogenic industrial and air pollutants (asbestos, uranium, arsenic, nickel, chromium, iron oxides, coal dust and radioactive dusts), radon gas concentrations, and familial susceptibility. Survival after diagnosis is poor: only one of seven patients lives for 5 years. However, if detected early (before spreading from the lungs), survival rates rise for most people. Radiofrequency ablation (RFA) is a promising therapy for patients with small lung tumors. Synonym: bronchogenic carcinoma See: illustration

Treatment

Treatment includes lung surgery, radiation therapy, and chemotherapy usually in combination.

Patient care

Staging determines the extent of the disease and aids in planning treatment and predicting the prognosis. Lung cancer is relatively difficult to cure but much easier to prevent. Children and adolescents should be discouraged from smoking tobacco products, and current smokers should be assisted in their efforts to quit, e.g., through referrals to local branches of the ACS, smoking-cessation programs, individual counseling, or group therapy.

Screening and Public Health

Chest x-rays do not show small, early cancers, but CT scanning can be used to screen people who have a long history of smoking and who are 50 to 60 years old. In this high-risk group, screening detects the disease in its early stages when it is most likely to be curable. However, since screening is very expensive, and since there are millions of smokers, the public health costs of mass screening are high compared with the cost of encouraging smokers to quit or of teaching teenagers not to start smoking.

oral cavity cancer

Squamous cell carcinoma of the mouth or tongue. Oral cavity cancers are only rarely caused by salivary gland tumors or sarcomas.

ovarian cancer

Any malignant growth in an ovary. About 85% to 90% of ovarian cancers arise from the surface epithelium of the ovary. In the U.S. in 2008, the ACS estimated there would be about 21,600 new patients diagnosed with ovarian cancer and about 15,200 deaths from the disease. Most cases (70%) are diagnosed when the disease is already at an advanced stage because early detection methods are still unsatisfactory. The early symptoms of the disease are often nonspecific and often mimic irritable bowel (constipation, vague abdominal pain, bloating). Initial laboratory studies (routine blood tests and x-rays) are often unremarkable.

Currently, more women die of epithelial ovarian cancer than of all other gynecological cancers combined. A small percentage of patients with ovarian cancer may have a hereditary predisposition, e.g., they have BRCA-1 or BRCA-2 genes. High-risk women include those with multiple first-degree relatives (mother, sister, daughter) or second-degree relatives (aunt, grandmother, cousin) with histories of breast or ovarian cancer. Preventive surgery to remove the ovaries and fallopian tubes is the only way such women can significantly reduce their risk.

Patient care

Ovarian cancer patients may feel threatened or vulnerable. They benefit from pretreatment support and education. Health care professionals address the patient's psychosocial needs while preparing her for treatment and manage the potential adverse reactions and the treatment and changes related to advancing disease.

The first step in care is typically surgical debulking of the tumor. In this phase of care, the surgical oncologist attempts to remove not only the primary tumor, but also as many small tumorlets found within the peritoneum. The patient and family should be taught about the extensive surgical procedure and what to expect after surgery. After surgery, the patient is monitored for infection, circulatory complications, fluid and electrolyte imbalances, and pain. The patient who is to receive chemotherapy should be taught about major adverse reactions to the usual medications employed, taxanes and platinum-based drugs, such as fatigue, nausea and vomiting, hair loss, diarrhea, constipation, mucositis, neuropathy, arthralgia and myalgia, difficulty concentrating (chemobrain), and myelosuppression, as well as about measures to be taken to prevent and manage these problems. Chemotherapy may be given directly into the peritoneum or intravenously. Depression, anger, frustration, and anxiety are common.

After the acute phase of treatment, the patient may undergo premature menopause; loss of fertility; alterations in body image, sexual function, and family relationships; impaired functional capacity; financial difficulties; and loss of spiritual well-being. The patient should be assessed for mood changes, inability to concentrate, fatigue, insomnia, and other symptoms of depression. Her medical history, current medications and treatments, nutritional status, pain rating, elimination pattern, and sexual history should be reviewed for factors that contribute to depression. Participating in a support group, meeting with mental health professionals, and taking an antidepressant or anti-anxiety medication can help alleviate depression and anxiety.

Advancing or relapsing ovarian cancer may cause complications. These may include development of ascites, intestinal obstruction, deep vein thrombosis, malnutrition and cachexia, lymphedema, and pleural effusion. Current five-year survival rates for ovarian cancer are about 30% to 40%. If ovarian cancer recurs after treatment or fails to regress with treatment, palliative and end-of-life care may aid both patients and their families.

cancer of the pancreas

Pancreatic cancer.

pancreatic cancer

Carcinoma of the pancreas. The American Cancer Society estimated there would be 37,700 new cases of the disease in the U.S. in 2008, with 34,300 deaths caused by the illness that year. Although the causes of pancreatic cancer are unknown, it has been found in more men than women, more blacks than whites, more smokers than nonsmokers, and more patients with a history of chronic pancreatitis and diabetes mellitus than without. When cancer occurs in the head of the pancreas, where it may obstruct the bile ducts and cause jaundice, the disease is most likely to be diagnosed at an early stage, when it may be most responsive to therapy. Surgical excision of the tumor and treatment with chemotherapy or radiotherapy may prolong survival in some patients. Only 4% of victims of pancreatic cancer survive 5 years. Synonym: carcinoma of the pancreas; cancer of the pancreaspancreatic carcinoma

primary cancer

The original cell or tissue type from which a metastatic cancer arises.

prostate cancer

See: prostate cancer

scirrhous cancer

Hard cancer.

skin cancer

A broad term that includes basal cell carcinomas, squamous cell carcinomas, and melanomas. Together, these skin cancers are the most common cancers in the U.S. They are all associated with excessive exposure to ultraviolet light, e.g., sun exposure. See: basal cell carcinoma; squamous cell carcinoma; melanoma

Patient care

According to the U.S. Preventative Services Task Force (USPSTF), benefits from routine screening for skin cancers with a total body skin examination are unproven, even in high-risk patients.

stomach cancer

Gastric cancer.

terminal cancer

Widespread or advanced cancer, from which recovery is not expected.

testicular cancer, germ-cell

Any of a group of testicular cancers that include choriocarcinomas, embryonal carcinomas, seminomas, spermatocytic seminomas, sex cord tumors, teratomas, and tumors with mixtures of several different malignant cell types.

cancer of unknown primary site

Disseminated cancer in which the original tissue type is uncertain. Such cancers generally have poor prognoses.

Etiology

Patients with such cancers are usually evaluated for tumors that might respond well to therapy, such as a lymphoma, a thyroid cancer, a germ cell tumor, or neoplasms of the breast or prostate.

cancer of uterus

A malignant neoplasm of the uterus, usually of the endometrium, found most often in women over 50. Other uterine cancers include those that arise in the muscular wall of the uterus (sarcomas), cervical cancers, and trophoblastic cancers. Symptoms may include post menopausal bleeding, bleeding between periods, and irregular, long, heavy periods. Pain during urination and during intercourse may be reported. Diagnosis of endometrial cancer is made by endometrial biopsy. The most common treatment is hysterectomy, although radiation and hormone therapy may be used. See: Bethesda System, The; cervical cancer; cervical intraepithelial neoplasia

vulvar cancer

Any malignant neoplasm of the vulva. Of these, 90% are squamous cell carcinomas; the rest are caused by adenocarcinomas, sarcomas, or Paget's disease.

Vulvar cancer accounts for 4% of all gynecological malignancies. More than 50% of cases occur in postmenopausal women between 65 and 70. Generally, vulvar cancers are localized, slow-growing, and marked by late metastasis to the regional lymph nodes. Treatment may include surgery and/or radiation therapy. See: vulvectomy

*Excludes basal and squamous cell skin cancers and in situ carcinomas except urinary bladder. Carcinoma in situ of the breast accounts for about 67,770 new cases annually, and melanoma in situ accounts for about 54,020 new cases annually. Estimates of new cases are based on incidence rates from the NCI SEER program, 1995 to 2004. SOURCE: ©2008, American Cancer Society, Inc., Surveillance Research
Estimated New CasesEstimated Deaths
MaleFemaleMaleFemale
All sites745,180692,000294,120271,530
Oral cavity & pharynx25,31010,0005,2102,380
Esophagus12,9703,50011,2503,030
Stomach13,1908,3106,4504,430
Colon & rectum77,25071,56024,26025,700
Liver & intrahepatic bile duct15,1906,18012,5705,840
Pancreas18,77018,91017,50016,790
Lung & bronchus114,690100,33090,81071,030
Melanoma-skin34,95027,5305,4003,020
Breast1,990182,46045040,480
Uterine corpus40,1007,470
Ovary21,65015,520
Prostate186,32028,660
Urinary bladder21,23017,5809,9504,150
Kidney & renal pelvis33,13021,2608,1004,910
Brain & other nervous system11,78010,0307,4205,650
Thyroid8,93028,410680910
Non-Hodgkin lymphoma35,45030,6709,7909,370
Leukemia25,18019,09012,4609,250
*Note: Cancer screening tests are most likely to be useful when: (1) the cancer is common and deadly; (2) the test reliably distinguishes between healthy and diseased people; (3) early detection of the disease leads to improved treatments; (4) treatments are safe and well-tolerated; (5) the psychological effects of test results are addressed sensitively and carefully; (6) the tests are applied to people who will truly benefit from them.
TestTo DetectDiscussion
Breast self-examinationBreast cancerMonthly self-examination by women is a noninvasive way to screen for changes in the breast. This method detects many benign and cancerous lumps, but its ability to prolong life is still debated.
MammographyBreast cancerMammography is clearly effective screening in women over 50. Most mammograms are obtained by women in their 40s. The incidence of cancer is higher in later life, when mammography use tends to decline.
Digital rectal examination (DRE)Colorectal cancer, prostate cancerDRE is easy to perform and inexpensive but its cancer screening value is unproven; and, when it detects cancers, there is no proof that the test results in better patient outcomes. In addition, DRE detects a very small number of cancers, only those within the reach of the examiner.
Fecal occult blood testColorectal cancerIn people over 50, testing stool specimens for hidden bleeding detects many cancers; this detection results in earlier treatment and prolongation of life. The accuracy and value of the test relative to sigmoidoscopy and colonoscopy are uncertain.
Chest x-ray, sputum cytology, CT of the chestLung cancerProspective studies have yielded conflicting results for any method of screening for lung cancer in smokers, and the costs of screening, e.g., with computed tomography of the chest, may be prohibitive. The tests are of no value to nonsmokers.
Prostate specific antigen (PSA)Prostate cancerPSA testing detects many previously undetected prostate cancers but may result in increased death and disease due to complications from subsequent surgery. Refinements in its application may improve its usefulness as a screening tool.
Genetic testingFor predisposition to a variety of cancersThe predictive value of genetic testing for cancer is very small. Experts are debating the emotional and ethical consequences of genetic cancer screening tests.

colorectal cancer

Abbreviation: CRC
A malignancy of the colon or rectum. It is the second leading cause of cancer deaths in the U.S. At some time during their lives 6% of Americans will be diagnosed with the disease. In 2008 the ACS estimated that 154,000 Americans would be newly diagnosed with colorectal cancer and that it would cause 50,500 deaths.

Etiology

The cancer occurs more often in people with a family history of the disease, those with familial adenomatous polyposis, and in those with inflammatory bowel diseases such as ulcerative colitis. It also occurs more often in people who are obese than in those who are not and in those who consume a high fat, low-fiber diet.

Symptoms

Symptoms may be absent or may include change in the usual pattern of bowel habits, esp. in those over 40; recent onset of constipation, diarrhea, or tenesmus in an older patient; bright red or dark blood in the stool. Laboratory findings may include iron-deficiency anemia or positive fecal occult blood tests.

Diagnosis

Diagnosis may be suggested by findings on digital rectal examination, anoscopy, flexible or rigid sigmoidoscopy, colonoscopy, virtual colonoscopy, or barium enema examination. It is confirmed by biopsy of suspicious lesions. Prevention includes screening of asymptomatic men and women of average risk starting at age 50, annual home fecal occult blood testing (over a three-day period), and colonoscopy every 10 years. During colonoscopy, removal of benign polyps prevents progression to malignant tumors. If polyps are found, colonoscopy should be repeated in 3 to 5 years (depending on the presence of other risk factors). Detection of colorectal cancer at an early stage via colonoscopy offers patients a very high likelihood of cure rate at 5 years. Neither digital rectal examination nor testing of a single stool specimen from the digital exam provides adequate screening. Patients at increased risk for colorectal cancer (those who have had previous colorectal adenomas or resected cancers or a history of ulcerative colitis or of colon cancer in a first-degree relative younger than 60) should undergo screening more frequently and at an earlier age. When colorectal carcinoma is diagnosed, additional tests are conducted to determine the stage of the disease (chest radiographs, CT, MRI, and blood studies, including carcinoembryonic antigen levels, and liver function studies).

Treatment

Surgical resection performed by laparotomy, minimally invasive surgery, microsurgery, or laparoscopy can cure localized colorectal cancer. Whatever procedure is used, the type of surgery depends on the location of the tumor, and the goal of the surgery is removal of the malignant tumor and adjacent tissue and any lymph nodes that may contain cancer cells. Adjuvant therapies may include chemoembolization of blood vessels that feed the primary tumor or metastases; radiation therapy; brachytherapy; chemotherapy; or monoclonal antibody therapy. Carcinoembryonic antigen is helpful in monitoring patients during and following treatment to determine effectiveness and detect recurrence or metasasis.

Patient care

Health care providers should teach patients the importance of colorectal screening and indicate applicable lifestyle modifications (a low-fat diet, maintenance of a normal body mass index). Patients with familial colon cancer syndromes, such as familial adenomatous polyposis, should be counseled about the need for close surveillance by professional gastroenterologists.

Aspirin and other nonsteroidal anti-inflammatory drugs appear to reduce the number of colon polyps, thus decreasing the risk of developing colorectal cancer. Patients interested in such therapy should discuss its potential risks and benefits with their health care providers.

Patients diagnosed with colorectal cancer who undergo surgery need counseling about the operation, the duration of recovery, and, in many cases, the use of a postoperative colostomy . Before surgery, a stomal therapist consults with the surgeon regarding appropriate stoma location, and the abdomen is marked. The therapist answers questions from the patient and family and begins to develop a relationship that will support the patient through postoperative care and teaching. Patient and family are encouraged to access the ACS (800-ACS-2345 or www.cancer.org) for additional information.

Synonym: carcinoma of the colon; colorectal carcinomaSee also: cancer
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