breast cancer
Noun | 1. | breast cancer - cancer of the breast; one of the most common malignancies in women in the US |
单词 | breast cancer | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
释义 | breast cancer
breast cancerbreast cancer,cancercancer,in medicine, common term for neoplasms, or tumors, that are malignant. Like benign tumors, malignant tumors do not respond to body mechanisms that limit cell growth. ..... Click the link for more information. that originates in the breast. Breast cancer is the second leading cause of cancer death in women (following lung cancerlung cancer, cancer that originates in the tissues of the lungs. Lung cancer is the leading cause of cancer death in the United States in both men and women. Like other cancers, lung cancer occurs after repeated insults to the genetic material of the cell. ..... Click the link for more information. ). Although the vast majority of the cases occur in women, some men also get breast cancer. Even allowing for improvements in detection (i.e., the introduction of routine mammography), there has been a long-term gradual increase in the incidence of breast cancer since the early 1970s, but because of the more effective treatment afforded by such early detection, overall mortality began to decrease by the mid-1990s. Breast cancers can arise in the lobes or lobules (lobular carcinoma) or in the ducts (ductal carcinoma) of the breast. Lobular carcinoma often affects both breasts. CausesEpidemiological study has identified certain risk factors that increase the possibility that a woman will get breast cancer, although not all women with breast cancer have these traits, and many women with all of these traits do not develop the disease. Risk factors include age (the incidence of breast cancer is rare in women under 35—most cases occur in women over 60); a history of breast cancer in a close blood relative; and a history of breast cancer or benign proliferative breast disease. A high cumulative exposure to female sex hormones (estrogen and progesterone) appears to increase the risk of some breast cancers. Hormonally related risk factors include early menarch (before age 12), late menopause (after age 55), having no children or postponing childbirth, and obesity in women over 50. Many other possible associations are under study, such as those relating to postmenopausal estrogen replacement, alcohol and fat consumption, lack of exercise, and exposure to pesticides and other environmental chemicals. A 2002 report on the association of estrogen replacement therapy with an increased risk of breast cancer led to a large drop in prescriptions for the drugs used in such therapy; a coincident drop in the incidence of breast cancer tumors, especially estrogen-positive tumors, which apparently could not be accounted for by other causes, strongly suggested a link between the two. Tumors in women of African descent are known to be particularly aggressive. Like all cancers, breast cancers result from changes in the structure or function of genes that are key to the regulation of cellular growth, differentiation, or repair. Acquired changes in a number of specific genes have been associated with the disease; these are changes that occur during a person's lifetime but are not inherited or passed on. About 5% of women with breast cancer have an inherited susceptibility to the disease, and most of these women have an inherited mutation in one of two genes. In 1994 it was discovered that women who inherit a mutated BRCA1 gene have an almost 85% chance of developing breast cancer and an increased chance of developing uterine cancer. BRCA1 normally acts to prevent tumors by repairing damage to the genetic material caused by oxidation, a chemical process that in the body occurs naturally during metabolism. Defective BRCA1 genes cannot repair this damage, allowing its effects to accumulate over time. Cells with oxidative damage to the genes that control their growth can proliferate, or become cancerous. The defective gene can be inherited from either parent, but appears to cause breast cancer only in women. Young women who get breast cancer often come from families that carry a BRCA1 mutation. BRCA1 mutations account for about half of known hereditary breast cancers. Another gene, named BRCA2, has also been identified. BRCA2 mutations have been associated with both female and rare male breast cancers. The two genes may also play a role in some ovarian cancers and sporadic (nonhereditary) breast cancer cases. Early Detection and PreventionMonthly breast self-examination and regular mammographymammography, TreatmentIn most cases, treatment for breast cancer begins with surgical excision of the tumor. Modern treatment attempts to preserve as much tissue as possible for both functional and cosmetic reasons. This may mean a lumpectomy (simple excision of only the cancerous tumor) or mastectomymastectomy Many women who have had a mastectomy decide to have breast reconstruction surgery. This reconstruction is done with breast implantsbreast implant, BibliographySee Y. Hirshaut and P. I. Pressman, Breast Cancer: The Complete Guide (3d ed. 2000). See also publications of the National Cancer Institute, the American Cancer Society, the National Breast Cancer Association, and the National Lymphedema Network. breast cancerBreast cancerDefinitionBreast cancer is caused by the development of malignant cells in the breast. The malignant cells originate in the lining of the milk glands or ducts of the breast (ductal epithelium), defining this malignancy as a cancer. Cancer cells are characterized by uncontrolled division leading to abnormal growth and the ability of these cells to invade normal tissue locally or to spread throughout the body, in a process called metastasis. DescriptionBreast cancer arises in the milk-producing glands of the breast tissue. Groups of glands in normal breast tissue are called lobules. The products of these glands are secreted into a duct system that leads to the nipple. Depending on where in the glandular or ductal unit of the breast the cancer arises, it will develop certain characteristics that are used to sub-classify breast cancer into types. The pathologist will note the subtype at the time of evaluation with the microscope. Ductal carcinoma begins in the ducts, lobular carcinoma has a pattern involving the lobules or glands. The more important classification is related to the evaluated tumor's capability to invade, as this characteristic defines the disease as a true cancer. The stage before invasive cancer is called in situ, meaning that the early malignancy has not yet become capable of invasion. Thus, ductal carcinoma in situ is considered a minimal breast cancer. How breast cancer spreadsThe primary tumor begins in the breast itself, but once it becomes invasive, it may progress beyond the breast to the regional lymph nodes or travel (metastasize) to other organ systems in the body and become systemic in nature. Lymph is the clear, protein-rich fluid that bathes the cells throughout the body. Lymph will work its way back to the bloodstream via small channels known as lymphatics. Along the way, the lymph is filtered through cellular stations known as nodes, thus they are called lymph nodes. Nearly all organs in the body have a primary lymph node group filtering fluid that comes from that organ. In the breast, the primary lymph nodes are under the armpit, or axilla. Classically, the primary tumor begins in the breast and the first place to which it is likely to spread is the regional lymph nodes. Cancer, as it invades in its place of origin, may also work its way into blood vessels. If cancer gets into the blood vessels, the blood vessels provide yet another route for the cancer to spread to other organs of the body. Breast cancer follows this classic progression though it often becomes systemic or widespread early in the course of the disease. By the time one can feel a lump in the breast it is often 0.4 inches, or one centimeter, in size and contains roughly a million cells. It is estimated that a tumor of this size may take one to five years to develop. During that time, the cancer may metastasize, or spread by lymphatics or blood to areas elsewhere in the body. When primary breast cancer spreads, it may first go to the axillary nodes. If this occurs, regional metastasis exists. If it proceeds elsewhere either by lymphatic or blood-borne spread, the patient develops systemic metastasis that may involve a number of other organs in the body. Favorite sites of systemic involvement for breast cancer are the lung, bones, liver, skin, and soft tissue. As it turns out, the presence of, and the actual number of, regional lymph nodes containing cancer remains the single best indicator of whether or not the cancer has become widely metastatic. Because tests to discover metastasis in other organs may not be sensitive enough to reveal minute deposits of cancer cells, the evaluation of the axilla for regional metastasis becomes very important in making treatment decisions for this disease. If breast cancer spreads to other major organs of the body, its presence will compromise the function of those organs. Death is the result of extreme compromise of vital organ function. DemographicsEvery woman is at risk for breast cancer. If she lives to be 85, there is a one in eight chance (12%) that she will develop breast cancer sometime during her life. As a woman ages, her risk of developing breast cancer rises dramatically regardless of her family history. The breast cancer risk of a 25-year-old woman is only one out of 19,608; by age 45, it is one in 93. In fact, fewer than 5% of cases are discovered before age 35 and the majority of all breast cancers are found in women over age 50. In 2008, about 182,500 new cases of breast cancer and 67,800 cases of cancer in situ were diagnosed in the United States. About 40,000 women die of breast cancer each year; breast cancer is the second leading cause of cancer death in women. However, in the United States, there 2.5 million breast cancer survivors. Deaths from breast cancer are declining in recent years, a reflection of earlier diagnosis from screening mammograms, improving therapies and a dramatic decrease in the use of hormone replacement therapy (HRT) in post-menopausal women. Causes and symptomsAll cancer is thought to occur because of small changes (mutations) in genes. A gene is a small packet of deoxyribonucleic acid (DNA), the genetic master molecule of all cells that is inherited from each parent. Genes control all aspects of development and metabolism. Small changes in the structure of genes can cause changes in proteins that regulate metabolic functions. In healthy cells, cell division is controlled by proteins regulated by genes. Specific genes make proteins that signal healthy cells when to stop dividing. In cancer, the controlling gene(s) is damaged or mutated and does not produce the proteins necessary to signal cells to stop dividing. The mutations that cause breast cancer do not have a single cause. Genetic, environmental, and lifestyle factors all play a role in determining who gets breast cancer. Although men can get breast cancer, women are 100 times more likely to develop the disease. There are a number of risk factors for the development of breast cancer; however, among experts there is some disagreement about how important each of these factors is. Risk factors include:
HRT provides significant relief of menopausal symptoms, prevention of osteoporosis, and possibly protection from cardiovascular disease and stroke. While physicians have long known a small increased risk for breast cancer was linked to use of HRT, a landmark study released in 2003 proved the risk was greater than thought. The Women's Health Initiative found that even relatively short-term use of estrogen plus progestin is associated with increased risk of breast cancer, diagnosis at a more advanced stage of the disease, and a higher number of abnormal mammograms. Of all the risk factors listed above, family history is the most important. Some studies have found that about half of all familial breast cancer cases (families in which there is a high breast cancer frequency) have mutations affecting the genes BRCA-1 or BRCA-2. Other genes (e.g., ATM, CHEK2, p53, PTEN) have been identified that may influence the development of breast cancer, but their impact is much less than the BRCA genes. Nevertheless, breast cancer due to heredity is only a small proportion of breast cancer cases; only 5%-10% of all breast cancer cases will be women who inherited a high susceptibility through their genes. Although there are many recognized risk factors, it is important to note that more than 70% of women who get breast cancer have no known risk factors. Having several risk factors may increase a woman's chance of developing breast cancer, but the interplay of predisposing factors is complex. In addition to those accepted factors listed above, some studies suggest that high-fat diets, obesity, or the use of alcohol may contribute to the risk profile. Not all lumps detected in the breast are cancerous. Fibrocystic changes in the breast are extremely common. Also known as fibrocystic condition of the breast, fibrocystic changes are a leading cause of non-cancerous lumps in the breast. Fibrocystic changes also cause symptoms of pain, swelling, or discharge and may become evident to the patient or physician as a lump that is either solid or filled with fluid. Complete diagnostic evaluation of any significant breast abnormality is mandatory because, although women commonly develop fibrocystic changes, breast cancer is common also, and the signs and symptoms of fibrocystic changes overlap with those of breast cancer. Certain benign changes in the breast may now be linked to increased risk for breast cancer. DiagnosisThe diagnosis of breast cancer is accomplished by the biopsy of any suspicious lump or mammographic abnormality that has been identified. (A biopsy is the removal of tissue for examination by a pathologist. A mammogram is a low-dose, 2-view, x-ray examination of the breast.) The patient may be prompted to visit her doctor upon finding a lump in a breast, or she may have noticed skin dimpling, nipple retraction, or discharge from the nipple. A patient may not have noticed a symptom or abnormality, before a lump was detected by a screening mammogram. When a patient has no signs or symptomsScreening involves the evaluation of women who have no symptoms or signs of a breast problem. Mammography has been helpful in detecting breast cancer that cannot be identified on physical examination. More than 90% of all breast cancers are detected by mammogram screening. However, about 10% of breast cancer does not show up on mammography, and a similar number of patients with breast cancer have an abnormal mammogram and a normal physical examination. These figures emphasize the need for regular examination as part of the screening process. ScreeningAll women are encouraged to do regular, monthly breast self-examinations. This involves feeling the breasts for any abnormal lumps or pain. If an uncertainty or a lump is found, evaluation by an experienced physician and a mammogram is recommended. The American Cancer Society (ACS) has made recommendations for the use of mammography on a screening basis. In 2009, the ACS guidelines recommended that women should begin annual screening at age 40 For women at high risk for breast cancer, the ACS recommends beginning screenings at an earlier age, having screening at more frequent intervals, and having magnetic resonance imaging (MRI) screening in addition to a standard mammogram. A list of conditions considered to put women at high risk for breast cancer can be found on the ACS Web site. Because of the greater awareness of breast cancer in recent years, screening evaluations by examinations and mammography are performed much more frequently than in the past. As a result, the number of breast cancers diagnosed has increased, but the disease is being diagnosed at an earlier stage than previously. The earlier the stage of disease at the time it is discovered, the better the long-term outcome (prognosis) becomes. When a patient has physical signs or symptomsA common finding that leads to diagnosis is the presence of a lump within the breast. Skin dimpling, nipple retraction, or discharge from the nipple are less frequent initial findings prompting biopsy. Though bloody nipple discharge is distressing, it is most often caused by benign disease. Skin dimpling or nipple retraction in the presence of an underlying breast mass on examination is a more advanced finding. Actual skin involvement, with swelling (edema) or ulceration of the skin, are late findings. The presence of a breast lump is a common sign of breast cancer. If the lump is suspicious and the patient has not had a mammogram by this point, a study should be done on both breasts prior to anything else so that the original characteristics of the lesion can be studied. The opposite breast should also be evaluated mammographically to determine if other problems exist that were undetected by physical examination. Whether an abnormal screening mammogram or one of the signs mentioned above followed by a mammogram prompted suspicion, the diagnosis is established by obtaining tissue by biopsy of the area. There are different types of biopsy, each used with its own indication. If signs of widespread metastasis are already present, biopsy of the metastasis itself may establish diagnosis. BiopsyDepending on the situation, different types of biopsy may be performed. The types include incisional and excisional biopsies. In an incisional biopsy, the physician takes a sample of tissue, and in excisional biopsy, the mass is removed. Fine needle aspiration biopsy and core needle biopsy are kinds of incisional biopsies. Fine needle aspiration biopsyIn a fine needle aspiration biopsy, a fine-gauge needle may be passed into the lesion and cells from the area suctioned into the needle can be quickly prepared for microscopic evaluation (cytology). (The patient experiencing nipple discharge also can have a sample taken of the discharge for cytological evaluation.) Fine needle aspiration is a simple procedure that can be done under local anesthesia, and will tell if the lesion is a fluid-filled cyst or whether it is solid. The sample obtained will yield much diagnostic information. Fine needle aspiration biopsy is an excellent technique when the lump is palpable and the physician can easily hit the target with the needle. If the lesion is a simple cyst, the fluid will be evacuated and the mass will disappear. If it is solid, the diagnosis may be obtained. Care must be taken, however, because if the mass is solid and the specimen is non-malignant, a complete removal of the lesion may be appropriate to be sure. Core needle biopsyCore needle biopsies also are obtained simply under local anesthesia. The larger piece of tissue obtained with its preserved architecture may be helpful in confirming the diagnosis short of open surgical removal. An open surgical incisional biopsy is rarely needed for diagnosis because of the needle techniques. If there remains question as to diagnosis, a complete open surgical biopsy may be required. Excisional biopsyWhen performed, the excisional (complete removal) biopsy is a minimal outpatient procedure often done under local anesthesia. Non-palpable lesionsAs screening increases, non-palpable lesions (abnormalities that can not be felt by hand examination) demonstrated only by mammography are becoming more common. The use of x rays and computers to guide the needle for biopsy or to place markers for the surgeon performing the excisional biopsy are commonly employed. Some benign lesions can be fully removed by multiple directed core biopsies. These techniques are very appealing because they are minimally invasive; however, the physician needs to be careful to obtain a good sample. Other testsIf a lesion is not palpable and has simple cystic characteristics on mammography, ultrasound may be used both to determine that it is a cyst and to guide its evacuation. Ultrasound may also be used in some cases to guide fine needle or core biopsies of the breast. Computed tomography (CT) scans are used only rarely in the evaluation of breast lesions. MRI is recommended for high-risk women and to follow up on suspicious findings from mammograms or for certain patients. TreatmentStagingOnce diagnosis is established and before treatment is begun, more tests are done to determine if the cancer has spread beyond the breast. These tests include a chest x ray and blood count with liver function tests. Along with the liver function measured by the blood sample, the level of alkaline phosphatase, an enzyme from bone, is also determined. A radionuclear bone scan may be ordered. This test looks at the places in the body to which breast cancer usually metastasizes. A CT scan also may be ordered. The physician will do a careful examination of the axillae to assess likelihood of regional metastasis. Sometimes, the physician will remove all of the axillary lymph nodes to assess breast cancer stage. However, recent studies show great success with sentinel lymph node biopsy. This technique removes the sentinel lymph node, or that lymph node that receives fluid drainage first from the area where the cancer is located. If this node is free of cancer, staging can be assigned accordingly. This method saves women the discomfort and side effects associated with removing additional lymph nodes in her armpit. Using the results of these studies, the stage of cancer is defined for the patient. This helps establish a treatment protocol and prognosis. In the United States, formal staging is done using the TNM system. This system considers the tumor size and how much it has grown (T), whether the cancer has spread to the lymph nodes (N), and whether it has metastasized (M) to distant sites in the body. Stages are summarized below.
TreatmentSurgery, radiation, and chemotherapy all may be used in the treatment of breast cancer. Depending on the stage, they will be used in different combinations or sequences to effect an appropriate strategy for the type and stage of the disease being treated. SurgeryHistorically, surgical removal of the entire breast and axillary lymph nodes, along with the muscles down to the chest wall (radical mastectomy), was performed as the preferred therapy for breast cancer. In the past 30 years, surgery remains a primary option, but other therapies have risen in importance. Recent studies have suggested that breast conserving treatment (as opposed to radical mastectomy) improves the quality of life for women without compromising survival. Ultimately, the extent of surgery depends on the type of breast cancer, whether the disease has spread, and the patient's age and health. If the tumor is less than 1.5 (4 cm) in size and located so that it can be removed without destroying the reasonable cosmetic appearance of the residual breast, just the primary tumor and a rim of normal tissue will be removed. The axillary nodes will still be removed for staging purposes, usually through a separate incision. Because of the risk of recurrence in the remaining breast tissue, radiation therapy is used to lessen the chance of local recurrence. This type of primary therapy is known as lumpectomy, (or segmental mastectomy), and axillary dissection. Sentinel lymph node biopsy, a technique for identifying which nodes in the axilla drain the tumor, has been developed to provide selective sampling and further lessen the degree of surgical trauma the patient experiences. When patients are selected appropriately based on the preoperative clinical stage, all of these surgical approaches have been shown to produce similar results. In planning primary surgical therapy, it is imperative that the operation is tailored to fit the clinical circumstance of the patient. The pathologic stage of the cancer is evaluated after surgical treatment and defines additional treatment. In addition to stage, other tests may be necessary to aid in decisions regarding additional adjuvant therapies. Adjuvant therapies are treatments used after the primary treatment to help ensure that no microscopic disease exists and to help prolong patients' survival time or reduce pain. Radiation therapyLike surgical therapy, radiation therapy is a local modality-it treats only the specific tissue exposed to radiation and not the rest of the body. Radiation is usually given post-operatively after surgical wounds have healed. The pathologic stage of the primary tumor is now known and this aids in treatment planning. The extent of the local surgery also influences the planning. Radiation may not be needed at all after modified radical mastectomy for stage I disease but is usually used when breast-preserving surgery is performed. If the tumor was extensive or if multiple nodes were involved, the field of tissue exposed will vary accordingly. Radiation is used as an adjunct to surgical therapy and is considered important to gaining local control of the tumor. In the past, radiation was used as an alternative to surgery on occasion. However, now that breast-preserving surgical protocols have been developed, primary radiation treatment of the tumor is no longer performed. Radiation also has an important role in the treatment of the patient with widespread (disseminated) disease, particularly if it involves the skeleton. Radiation therapy can affect pain control and prevention of fracture in this circumstance. ChemotherapySurvival after breast cancer surgery is improved by the addition of postoperative chemotherapy. Post-surgical chemotherapy therapy in patients who have no evidence of residual disease is now performed on the basis that some patients have metastases that are too small to be detectable. This occurs because it is unlikely that the surgeon has removed every single cancerous cell. Loose cancer cells, if not killed by chemotherapy, may travel through the circulatory system and form new tumors elsewhere. Chemotherapy may also be given in some circumstances before surgery. Chemotherapy is administered either orally or by injection into a blood vessel and usually involves multiple drugs. It is given in cycles, followed by a period of time for recovery, followed by another course of drugs. Chemotherapy can produce significant side effects, including nausea and vomiting, temporary hair loss, mouth or vaginal sores, fatigue, weakened immune system, and infertility. Complementary therapies are often helpful in reducing some of these side effects. Hormone therapyMany breast cancers, particularly those originating in post-menopausal women, are responsive to hormones. These cancers have receptors on their cells for the hormone estrogen. Part of the post-surgery primary tumor assessment is evaluation for the presence of estrogen and progesterone receptors. If they are present on the cancer cells, altering the hormone status of the patient will slow tumor growth and have a positive impact on survival. Hormonal status may be changed with drug therapy. The drug tamoxifen binds to estrogen receptors on the cancer cells, so that hormones cannot interact with the cells and stimulate their growth. If the patient has these receptors present, tamoxifen is commonly prescribed for five years as an adjunct to primary treatment. In women whose cancer cells have estrogen receptors, tamoxifen reduces the chance of breast cancer reoccurring by about 50%. Toremifene (Fareston) and fulvestrant (Faslodex) are drugs similar to tamoxifen in that they target hormone receptors on cancer cells. They are often used when cancer cells are unresponsive to tamoxifen. In addition, a new group of drugs called aromatase inhibitors that block the enzymes that produce estrogen in postmenopausal (but not premenopausal) women have been used to treat both early and late advanced breast cancer. These drugs include drugs are letrozole (Femara), anastrozole (Arimidex), and exemestane (Aromasin). Because of these agents, there is rarely any need for surgical removal of hormone-producing glands, such as the ovary or adrenal, that was sometimes necessary in the past. BiotherapeuticsBiotherapeutics are a type of targeted therapy. Large amounts of antibodies of a single type (called monoclonal antibodies) that react with specific receptors on cancer cells are made in the laboratory. When given to the patient, they inactivate or destroy those cells containing that specific receptor, but do not react with other cells. Trastuzumab (Herceptin) and Lapatinib (Tykerb) target cells that contain a growth protein known as HER/2. Between 15% and 25% of women have breast cancer that responds to these drugs. Bevacizumab (Avastin) is a biotherapeutic used to treat breast cancer that has metastasized. It helps prevent tumors from becoming established by interfering with the growth of blood vessels into the tumor. Without access to nutrients in the blood, the tumors cannot increase in size. Biotherapeutics are normally used in addition to chemotherapy drugs. Complementary adjuvant therapyComplementary treatments used along with conventional medicine are often successful in moderating side effects and improving the patient's quality of life. For example, acupuncture and guided imagery may be useful tools in treating pain symptoms and side effects of chemotherapy associated with breast cancer. Acupuncture involves the placement of a series of thin needles into the skin at targeted locations on the body, known as acupoints, in order to harmonize the energy flow within the human body. Guided imagery involves creating a visual mental image of pain. Once the pain can be visualized, the patient can adjust the image to make it more pleasing, and thus more manageable. Many herbal remedies are available to lessen pain symptoms and chemotherapy side effects such as nausea, and to promote relaxation and healing. However, breast cancer patients should consult with their healthcare professional before taking any herbal treatments. Depending on the preparation and the type of herb, these remedies may interact with and enhance or diminish the effects of other prescribed medications. One herb that is generally regarded as helpful in relieving the nausea that accompanies chemotherapy, is ginger (Zingiber officinale). PrognosisThe prognosis for breast cancer depends on the type and stage of cancer. Lymph node involvement is one of the best indicators of breast cancer survival rates. According to the American Cancer Society, As of 2009, the five-year survival rate for American women with carcinoma in situ and stage I breast cancer was 100%. The five-year survival rate for women with stage II breast cancer 86% About 53% of stage III patients survive five years, and about 20% of stage IV patients do so. PreventionWhile breast cancer cannot be prevented, making lifestyle choices that eliminate the risk factors listed above is both prudent and promotes general health and well being. While regular breast exams and screening mammograms will not prevent breast cancer, they significantly aid in its early detection and treatment, thus increasing the chances of survival. 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Cancer treatment Cancer diagnosis Hormone therapy Breast biopsy Breast cancer breast[brest]At the tip of each breast is an area called the areola, usually reddish in color; at the center of this area is the nipple. About 20 separate lactiferous ducts empty into a depression at the top of the nipple. Each duct leads from alveoli within the breast called lobules, where the milk is secreted. Along their length, the ducts have widened areas that form reservoirs in which milk can be stored. The ducts and lobules form the glandular tissue of the breasts. Connective tissue covers the glandular tissue and is itself sheathed in a layer of fatty tissue. The fatty tissue gives the breast its smooth outline and contributes to its size and firmness. ![]() ![]() As with other forms of cancer, early detection and prompt treatment of malignancy of the breast are the keys to eradication of the disease. Studies have shown that breast self-examination has contributed to earlier detection and improved survival rates. It should be done monthly; more than 90 percent of breast cancers are discovered by the patients themselves either by chance or by routine self-examination. The American Cancer Society reports that only about 69 percent of women polled in the past had done self-examination at any time during the past year and less than 29 percent did it routinely each month. Screening should begin by age 40 and should consist of a clinical examination every year and screening mammography every one or two years. Beginning at age 50, both the clinical examination and the mammography should be done once a year. mammography is considered to be the best diagnostic method for early detection when tumors are small and not readily found by palpation. Other diagnostic techniques include thermography, ultrasonography, magnetic resonance imaging, and computerized tomography, but none of these is believed to be as accurate as mammography. The first symptom noted is usually a lump or nodule in the breast tissue; however, dimpling of the breast skin or changes in the nipple may be noted before a lump is found. Diagnosis of a malignant tumor is confirmed by biopsy. Additional information can be obtained by calling the National Cancer Institute's Cancer Information Service Hotline at 1-800-4-CANCER. Statistics BC is the most common CA in women; occurs in 12% of all US women, killing 3.5%—it is the leading COD in women age 40–55; in Japan, BC is 1/5 as common as it is in the US; it has doubled from 1930s to 1990s—± 55 to 105/100,000 Statistics Incidence: 450/100,000/year, age 75, US; mortality 125/100,000/year, age 75 Diagnosis Self-, doctor examination, mammography, ultrasonography, biopsy Surveillance The American Cancer Society recommends a baseline mammogram at age 35 to 40; between 41 and 50, every other year, after age 50, annually; the thicker the bone, the greater the risk of BC; cause unknown, related to use of postmenopausal estrogens; ever active smokers have an odds ratio of 2.0 for breast CA, when compared to never active, never passive smokers Risk factors Breast feeding—6 months—decreases risk of BC; lactation and breast feeding before age 20 is associated with a RR of 0.54 Susceptibility genes BRCA1, BRCA2, genes for Li-Fraumeni syndrome, Cowden disease, Muir-Torre syndrome, ataxia-telangiectasia predispose to breast CA; such genes account for 1/5 of breast CA Chemotherapy Maximum effect with early treatment and maximum tolerable doses with cyclophosphamide, doxorubicin, fluorouracil Surveillance Early detection, monthly breast self-examination, mammography at age-appropriate intervals Therapeutic trends 1985–1993 Breast-conserving therapy, 31% 54%; axillary node dissection 52% 40%; RT 38% 54% breast cancerOncology An uncontrolled growth of abnormal breast tissue, usually epithelial in nature Statistics BC is the most common CA in ♀; occurs in 12% of all US ♀, killing 3.5%–it is the leading COD in ♀ age 40-55; in Japan, BC is1⁄5 as common as the US, but there has doubled from the mid-1930s to 1990s–± 55 to 105/105 StatisticsDeaths/Newly diagnosed44.5/185.7 Diagnosis Self- and physician examination, mammography, ultrasonography, biopsy Risk factors Breast feeding–≥ 6 months ↓ risk of BC; lactation and breast feeding before age 20 is associated with a RR of 0.54 Chemotherapy Maximum effect with early treatment and maximum tolerable doses with cyclophosphamide, doxorubicin, fluorouracil Surveillance Early detection, monthly breast self-examination, mammography at age-appropriate intervals Therapeutic trends 1985-1993 Breast-conserving therapy, 31%→54%; axillary node dissection 52%→40%; RT 38%→54%. See BRCA1, BRCA2.Breast cancer staging
breast cancer![]() EtiologyThere are several known risk factors for breast cancer. See: table SymptomsA dominant breast mass; bloody, brown, or serous discharge from a nipple; and/or breast nodularity or lumpiness are the most common symptoms of breast cancer. DiagnosisRegular breast self-examination, professional breast examination, and mammography are the keys to screening for breast cancer. All these screenings identify many more benign lesions than malignant ones, esp. in younger patients, and none of these techniques can definitively exclude breast cancer. Many mammographically detected lesions are benign, and about 15% of the time mammography will fail to detect lesions that are truly malignant. Digital mammography provides significantly better detection in women with dense breasts, those under age 50, and those who are premenopausal or perimenopausal. If a suspicious mass is identified, fine needle aspiration, core biopsy, or excisional biopsy must be used to obtain tissue for analysis. Ultrasonography can be used before biopsy to identify solid masses and cysts. Solid breast masses have a much greater chance of being malignant than cysts. Other imaging techniques used to help identify breast cancers include magnetic resonance imaging, positron emission tomography, and ductal imaging. See: table See: breast self-examination; double reading; mammography StagingThe size of tumors and their possible metastasis to the chest wall, skin, axillae, or distant sites all determine the stage of breast cancer. Lymphatic mapping during cancer surgery can be used to find metastases to sentinel lymph nodes and guide therapies. Staging provides important information about the need for particular forms of therapy and the prognosis. See: illustration CAUTION!A biopsy (obtained by fine needle aspiration, with a stereotactic core needle, or by surgical lumpectomy) is usually recommended for any breast mass that does not resolve spontaneously within one or two menstrual cycles and for all postmenopausal women. Negative results from mammography and ultrasonography are not always accurate enough to rule out a malignant diagnosis.TreatmentCombined modalities (including surgery, radiation, or drug therapies) are offered to many women with breast cancer, depending on their menopausal status and the stage of their disease at the time of diagnosis. Patients with stage I or II disease are offered either modified radical mastectomy (removal of the breast and 20 to 30 axillary lymph nodes) or lumpectomy with sentinal node or axillary dissection (as required) and radiotherapy, provided they have no contraindications to either of these choices. A variety of radiotherapy options are available, depending upon the individual patient's cancer. In premenopausal women with tumors larger than a centimeter, adjuvant chemotherapy prolongs survival, probably by eliminating microscopic metastases. Chemotherapeutic regimens commonly used include CMF (cyclophosphamide, methotrexate, and fluorouracil), CAF (cyclophosphamide, doxorubicin [Adriamycin], and fluorouracil), AC (doxorubicin [Adriamycin] and cyclophosphamide), doxorubicin (Adriamycin) followed by CMF, or FEC (fluorouracil, epirubicin, and cyclophosphamide). All of these agents are given several times in cycles of treatment. These same regimens are offered to vigorous postmenopausal women whose cancer has spread to axillary lymph nodes. Hormonal therapies like tamoxifen or raloxifene (two estrogen-receptor blockers) are also beneficial in patients with estrogen-receptor–positive tumors. Aromatase inhibitors (such as letrozole), and monoclonal antibodies (such as trastuzumab) may be prescribed to selected patients. After breast surgery, some women choose to have cosmetic restoration of the breast, either with saline- or silicone-filled implants or with tissue reconstructions made from the abdominal muscles. If breast cancer recurs after treatment, very high-dose chemotherapies are prescribed and peripheral stem cell transplantation is occasionally considered, but only in research settings. Bone metastases may be treated with monthly dosing of intravenous zoledronic acid (Zometa). See: ductal carcinoma in situ of breast Patient careThe patient's feelings and level of knowledge about her disease are determined. She is encouraged to express fears and concerns, and her family, supporters, or health care professionals stay with her during periods of anxiety or anguish. If surgery is planned, the procedure, postoperative care, and expected outcomes are explained. While undergoing chemotherapy, the patient is monitored for adverse reactions (such as nausea, vomiting, anorexia, stomatitis, gastrointestinal ulceration, anemia, leukopenia, thrombocytopenia, and bleeding), so that they can be managed early. Weight and nutrition status are evaluated. Skin is inspected for redness, irritation, or breakdown if radiation therapy is prescribed, and aloe or a prescribed cream is applied. Bisphosphate drugs (such as alendronate or zolendronic acid) are administered to prevent or treat bone metastases or hypercalcemia, but their use may be associated with osteonecrosis of the jaw. Comfort measures are used to promote relaxation and rest and to relieve anxiety. If immobility develops late in the disease, careful repositioning, excellent skin care, respiratory toilet, and low-pressure mattresses are used to prevent complications, e.g., skin breakdown, respiratory problems, pathological fractures. The patient's and family's coping abilities are evaluated, and referral for counseling and support services may be necessary. End-stage disease patients benefit from hospice care. Women judged to be at highrisk for breast cancer may have tamoxifen or ralozifene prescribed as preventative therapy. locally advanced breast cancerAbbreviation: LABC.triple negative breast cancerTriple negative disease.
breast cancerThe commonest form of cancer in women, affecting about 1 in 12 women in Britain. Early breast cancer hardly ever causes pain and the only sign is a slowly growing lump. Later signs are distortion of the normal breast contour by skin dimpling, indrawing of the nipple, bleeding from the nipple, an orange-skin appearance (peau d'orange) of the breast skin, and rubbery, firm, easily felt lymph nodes in the armpit. Mammography for non-dense breast tissue and ultrasound scanning for dense tissue are the most effective screening methods. Most cases are treated by lumpectomy and radiotherapy or chemotherapy. Chemotherapy is an integral part of the management of resected node-positive cancer. Various combinations of drugs such as doxorubicin, cyclophosphamide and the taxane paclitaxel are used.Breast Cancer
One in eight women in the United States will develop breast cancer in her lifetime. The Centers for Disease Control and Prevention report that breast cancer is the most common cancer among women and the second leading cause of cancer death after lung cancer for women in the United States. The American Cancer Society (ACS) estimates that there were 232,340 cases of breast cancer in 2013, and 39,620 women died from the disease in that year. If it is found in early stages (in situ with no node involvement), the 10-year survival rate is 70% to 75% compared with 20% to 25% when the nodes are positive. Breast cancer can recur even 20 to 30 years after the first diagnosis. Carcinoma of the breast stems from the epithelial tissues of the ducts and lobules. Ductal carcinoma is the most common type of breast cancer. Breast cancer is classified as either noninvasive or invasive. Noninvasive carcinoma refers to cancer in the ducts or lobules and is also called carcinoma in situ (5% of breast cancers). Invasive carcinoma (also known as infiltrating carcinoma) occurs when the cancer cells invade the tissue beyond the ducts or lobules. The rate of cell division of the cancerous growth varies, but it is estimated that the time it takes for a tumor to be palpable ranges from 5 to 9 years. When the cancer cells become invasive, they grow in an irregular or sunburst pattern that is palpated as a poorly defined lump or thickening. As the tumor continues to grow, fibrosis forms around the cancer, causing the Cooper’s ligaments to shorten, which results in dimpling of the skin. Advanced tumors will interrupt the lymph drainage, resulting in skin edema and an “orange peel” (peau d’orange) appearance. Untreated cancer may erupt on the skin as an ulceration. CausesThe origin of breast cancer is a complex interaction between the biologic and endocrine properties of the person and environmental exposures that may precipitate the mutation of cells to a malignancy. The greatest risk by far is family history of breast cancer. Other risk factors include European ancestry, residence in North America or Europe, an age greater than 40, personal history of breast cancer (three- to four-fold increased risk), history of benign breast disease, nulliparity or an age greater than 30 for first-time pregnancy, menarche before age 12, menopause after age 55, postmenopausal obesity (especially if the excess fat is in the waist area as opposed to the hips and thighs), and diethylstilbestrol (DES) exposure. Recent studies support an association of breast cancer with moderate alcohol intake, a high-fat diet, and prolonged hormonal replacement therapy. Other environmental factors include exposure to radiation (during childhood or significant chest radiation) or pesticide residues. Many women with breast cancer have no identifiable risk factors. Genetic considerationsBreast cancer is a feature of several cancer syndromes including Cowden’s syndrome, Li-Fraumeni syndrome, Peutz-Jeghers syndrome, Bloom’s syndrome, Werner’s syndrome, ataxia-telangiectasia, and xeroderma pigmentosum, but these syndromes account for less than 1% of all breast cancers. More familiar to most people are the nonsyndromic breast cancer susceptibility genes, which account for 5% to 10% of breast cancer cases. The two most widely known genes are BRCA1 and BRCA2, both tumor suppressor genes. The lifetime risk of becoming affected by breast cancer for mutation carriers has been estimated at between 60% and 88%. Breast cancer is considered a complex (multifactorial) disorder caused by both nongenetic and genetic factors. Several genes have been shown to contribute to susceptibility. These include the tumor suppressor genes CHEK2 and TP53 as well as BRCA3, BWSCR1A, TP53, BRIP1, RB1CC1, RAD51, and BARD1. Gender, ethnic/racial, and life span considerationsBreast cancer is predominantly a disease of women over the age of 40, with incidence rates increasing with age. The mean age of diagnosis for women is 61. The annual incidence of breast cancer is less than 60 per 100,000 individuals below age 40; 100 per 100,000 individuals by age 50; and nearly 200 per 100,000 individuals at age 70. Only 1% of breast cancer affects men, and it usually occurs when they are over the age of 60. The case of the elderly patient with breast cancer is essentially the same as with younger patients. Breast cancer rates among women with various ancestries follow: Non-Hispanic white: 125.4/100,000; black/African American: 116.1/100,000; Hispanic/Latina: 91.0/100,000; American Indian/Alaska Native: 89.2/100,000; Asian American/Pacific Islander: 84.9/100,000. While white women have a higher frequency of breast cancer, blacks/African Americans are more likely to die from the disease; this is attributed to late detection of the cancer and perhaps more aggressive tumors. Global health considerationsThe global incidence of breast cancer in women is 37.4 per 100,000 females. In developed countries, the incidence is almost three times higher than in developing nations. Rates are higher in developed Western nations likely because of lifestyle factors: dietary patterns, decreased physical activity, high rates of obesity, and the use of exogenous hormones for contraception and menopausal symptoms. AssessmentHistoryAssess the patient’s and family’s previous medical history of breast cancer or other cancers. Obtain a detailed history of hormonal and reproductive sequences and medications (specifically hormonal supplements). Assess lifestyle variables such as diet, exercise, alcohol use, and occupational history. Determine how, when, and by whom the lump was found (breast self-examination [BSE], mammogram, accident) and if any discharge from the breast was noted. Ask how much time elapsed between finding the lump and seeking professional care in order to estimate the length of time the tumor has been present. Proceed with the systemic review with attention to areas where metastasis is common. Physical examinationCommon symptoms include breast mass, change in breast size or shape, skin dimpling, recent nipple inversion, discharge, and/or axillary lumps. Inspect the breast skin for signs of advanced disease: the presence of inflammation, dimpling, orange peel effect, distended vessels, and nipple changes or ulceration. Palpate both breasts to evaluate the tissues and identify the mass. Examine the axillary and supraclavicular areas for enlarged nodes. You may note the tumor is firm and immovable. Assess the patient for pain or tenderness at the tumor site. PsychosocialPatients present a wide range of responses: denial, fighting spirit, hopelessness, stoic acceptance, anxious preoccupation. Elicit a careful and ongoing assessment of the patient’s feelings (anger, depression, anxiety, fear) and body image concerns. Identify the patient’s perceptions of how breast cancer will affect her role relationships, lifestyle, femininity, and sexuality. Be sure to include the husband or significant other and children in the psychological assessment to learn of their emotional needs. Diagnostic highlightsGeneral Comments: Because early diagnosis and treatment increase survival, the ACS recommends the following guidelines for early breast cancer detection:
Other Tests: Computed tomography (CT) scan; MRI; estrogen receptor (ER) assay and progesterone receptor (PR) assay; flow cytometry; DNA ploidy; full-field digital mammography (recently approved by the U.S. Federal Drug Administration but not widely used); computer-aided detection and diagnosis; ductogram Primary nursing diagnosisDiagnosisBody image disturbance related to significance of loss of part or all of the breastOutcomesBody image; Psychosocial adjustment: Life change; Acceptance: Health statusInterventionsBody image enhancement; Support group; Support system enhancement; Wound carePlanning and implementationCollaborativeTreatment and prognosis for breast cancer are based on the stage of disease at diagnosis according to the TNM classification (T = tumor size, N = involvement of regional lymph nodes, M = metastasis) (Table 1). It is now recognized that treatment of breast cancer requires a multimodal approach. Surgery and radiation, either alone or in combination, control cancer in the breast and regional lymph nodes. Chemotherapy and hormonal therapy are intended to provide systemic control. Adjuvant therapy (pharmacologic treatment given to patients with no detectable cancer after surgery) is often recommended because cancer cells can break away from the primary breast tumor and begin to spread through the bloodstream, even in the early stages of disease. These cells cannot be felt or detected on x-ray.
surgical.The goal of surgery is control of cancer in the breast and the axillary nodes. Most women have a choice of surgical procedures, but it depends on the clinical stage, tumor location, contraindications to radiation (pregnancy, collagen disease, prior radiation, multifocal tumors), and the presence of other health problems. Several types of surgical therapy are commonly available, as follows.modified radical mastectomy (total mastectomy).The most common surgical procedure for mastectomy removes the entire breast and some or all of the axillary nodes as well as the lining over the pectoralis major muscle. At times, the pectoralis minor muscle is removed. Contralateral prophylactic mastectomy (CPM) is being implemented in ductal carcinoma in situ (DCIS) to decrease the risk of cancer in the opposite breast. Rates of CPM have increased 148% from 1998 to 2005.breast-preserving surgeries.The breast-preserving surgeries combined with radiotherapy are recognized to be equivalent to modified radical mastectomy for stages I and II breast cancer for survival rates and local control.Sentinel lymph node biopsy, a procedure using a radioactive tracer to determine which lymph nodes need to be removed during a mastectomy, is under investigation. This procedure allows fewer lymph nodes to be removed, decreasing the uncomfortable side effect of lymphedema that can occur with surgery. complications of surgery.The complications of breast surgery may be infection, seroma (fluid accumulation at the operative site), hematoma, limited range of motion (ROM), sensory changes, and lymphedema. A seroma is usually prevented with the placement of a gravity drainage device (Hemovac, Jackson-Pratt) in the site for up to 7 days postoperatively. Drains are usually removed when drainage has decreased to about 30 cc per day. ROM for the lower arm is begun within 24 hours postoperation, and full ROM and other shoulder exercises are ordered by the surgeon after the drains are removed. Sensory changes include numbness, weakness, skin sensitivity, itching, heaviness, or phantom sensations that may last a year.radiation therapy.Radiotherapy is routinely given 2 to 4 weeks after breast-preserving surgery for stage I and stage II breast cancer. Sometimes it is indicated after modified radical surgery if four or more nodes are positive. The incision needs to be healed, and ROM of the shoulder should be restored. Radiotherapy may consist of an external beam to the breast for 4 to 6 weeks, by an experimental method called brachytherapy (interstitial iridium-192 implants) directly to the tumor site, or both. Radiation can be given at the same time as chemotherapy.chemotherapy/hormonal therapy.Combination chemotherapy is recommended for premenopausal and postmenopausal patients with positive nodes. Hormonal therapy is used to change the levels of hormones that promote cancer growth and increase survival time in women with metastatic breast cancer. Tumors with a positive ER assay (tumors that need estrogen to grow) have a response rate to hormonal therapy of 65% compared with a 10% response rate with a negative ER assay. PR assays that are also positive enhance endocrine therapy response even more. There is a 77% response rate if both ER and PR are positive as compared with a 5% response rate if both are negative.autologous bone marrow transplant (abmt).Certain patients (with chemosensitive tumors) with stage III cancer are being treated with high-dose chemotherapy preceded by removal of the patient’s bone marrow, which is then restored after chemotherapy.reconstruction.Approximately 30% of women who have mastectomies choose to have breast reconstruction (Table 2).
Almost all patients who have mastectomies are candidates. It can be immediate (at the time of mastectomy) or delayed for several years. Postoperatively, use a flow sheet every hour and assess adequate blood supply to the flap and donor site by evaluating the following: color (to verify that it is the same as skin from the donor area [not the opposite breast]), temperature (warm), tissue turgor (to verify that it is not tight or tense), capillary refill (a well-perfused flap will blanch for 1 to 3 seconds), and anterior blood flow using ultrasonic or laser Doppler. Unusual pain or decreased volume of drainage may indicate vascular impairment to the flap. Early detection of impaired circulation can be treated with anticoagulants or antispasmodics and possibly prevent further surgical interventions. Provide emotional support for the patient who is distraught over her appearance to reassure her the breast will look more normal with healing. The nipple and areola can be added 6 to 9 months later. Pharmacologic highlights
Other Drugs: Capecitabine, vinorelbine, and gemcitabine hydrochloride; carboplatin; methotrexate; raloxifene to reduce breast cancer risk; antiestrogen medications include fulvestrant; letrozole (taken after 5 years of tamoxifen to lower breast cancer reoccurrence) IndependentThe focus of nursing care for a patient with a mastectomy during the 2- to 3-day hospital stay is directed toward early surgical recovery. Teach pain management, mobility, adequate circulation, and self-care activities to prepare the patient for discharge. In the immediate postoperative period, keep the head of the bed elevated 30 degrees, with the affected arm elevated on a pillow to facilitate lymph drainage. Instruct the patient not to turn on the affected side. Place a sign at the head of the bed immediately after surgery with directions for no blood pressures, blood draws, injections, or intravenous lines on the arm of the operative side; this should help prevent circulatory impairment. Emphasize the importance of ambulation and using the operative side within 24 hours. Initially, the arm will need to be supported when the patient is out of bed. As ambulation progresses, encourage the patient to hang her arm at her side normally, keeping her shoulders back to avoid the hunchback position and to prevent contractures. Within 24 hours, begin with exercises that do not stress the incision. Teach the patient how to empty the drainage device (Hemovac or other), measure the drainage accurately, and observe for the color and consistency of the drainage. Create a flow sheet for record-keeping in the hospital, and send it home with the patient to use until the drain is removed. At the dressing change, begin teaching the dressing change procedure and the indications of complications such as infection (purulent drainage, redness, pain), presence of fluid collection, or hematoma formation at the incision. Be sensitive to the patient’s reactions upon seeing the incision for the first time with full realization that her breast is gone. Explain that phantom breast sensations and numbness at the operative site along the inner side of the armpit to the elbow are normal for several months because of interruptions of nerve endings. Women may have feelings of loss not only of their breast, but also of lifestyle, social interactions, sexuality, and even life itself. Patients often feel more comfortable expressing their feelings with nurses than with family members or the physician. Effective coping requires expression of feelings. Discuss the services and goals of Reach to Recovery (psychological and physical support). If the patient is willing, arrange for an in-hospital visit or early home visit. Evidence-Based Practice and Health PolicyBasu, M., Linebarger, J., Gabram, S.G., Patterson, S.G., Amin, M., & Ward, K.C. (2013). The effect of nurse navigation on timeliness of breast cancer care at an academic comprehensive cancer center. Cancer, 119(14), 2524–2531.
Documentation guidelines
Discharge and home healthcare guidelinespatient teaching.The patient can expect to return home with dressings and wound drains. Instruct the patient to do the following: Empty the drainage receptacle twice a day, record the amount on a flow sheet, and take this information along when keeping a doctor’s appointment; report symptoms of infection or excess drainage on the dressing or the drainage device; sponge bathe until the sutures and drains are removed; continue with daily lower arm ROM exercises until the surgeon orders more strenuous exercises; avoid caffeinated foods and drinks, nicotine, and secondary smoke for 3 weeks postoperatively. Review pain medication instructions for frequency and precautions.Teach precautions to prevent lymphedema after node dissection (written directions or a pamphlet from ACS is desirable for lifetime referral):
follow-up.Prepare the patient and family for a variety of encounters with healthcare providers (radiologist, oncologist, phlebotomist). Try to provide a continuity between the providers (yourself, the clinical nurse specialist, or a nurse consultant system, if available) as a resource for the patient or family to call with questions.Provide lists and information of local community resources and support groups for emotional support: Reach to Recovery, Y-ME, Wellness Center, Can Surmount, I Can Cope; a list of businesses that specialize in breast prostheses; phone numbers for ACS and the Cancer Information System. Recurrence is a lifetime threat. Inform the patient that it is necessary to continue monthly BSEs (even on the operative side) and annual mammogram and physician examinations of both the reconstructed and the nonreconstructed breasts. Be certain the patient can demonstrate an accurate BSE. Patient discussion about breast cancerQ. what is inflamatory breast cancer? Q. what are the risks for breast cancer? Q. Is it a breast cancer? My cousin, 30/female. She says that while she do some heavy work her right side breast is paining heavily. I am scared, whether is it a symptom of a breast cancer or something else. I like to help & comfort her? See BRCA breast cancer
Words related to breast cancer
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