olfactory neuroblastoma
ol·fac·to·ry neu·ro·blas·to·ma
esthesioneuroblastoma
A rare malignant neuroectodermal tumour of the nasal cavity in the retrobulbar region, middle cranial fossa, near the cribriform plate. It is thought to arise from the olfactory membrane of the sinonasal tract.Clinical findings
Bimodal age distribution, affecting those in the 2nd and 6th decades of life; presents as a unilateral nasal obstruction, epistaxis, anosmia and headache, accompanied by nonspecific symptoms similar to other intranasal lesions—i.e., congestion, rhinorrhoea.
DiffDx
Small round cell malignancies that occur in the sinonasal tract—e.g., sinonasal undifferentiated carcinoma, lymphoma, rhabdomyosarcoma and neuroendocrine carcinomas.
Prognosis
5-year survival 50–60%; late recurrence is common. Hyams’ grading system is used for grading; it incorporates architecture, rosette formation, mitoses, necrosis and pleomorphism, and correlates with survival.