olfactory neuroblastoma

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ol·fac·to·ry neu·ro·blas·to·ma

a rare, often slowly growing malignant tumor of primitive nerve cells, usually arising in the olfactory area of the nasal cavity.
Farlex Partner Medical Dictionary © Farlex 2012


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.
Small round cell malignancies that occur in the sinonasal tract—e.g., sinonasal undifferentiated carcinoma, lymphoma, rhabdomyosarcoma and neuroendocrine carcinomas.

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.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
References in periodicals archive ?
We retrieved 36 cases of Olfactory neuroblastoma from the surgical pathology database of Section of Histopathology, Aga Khan University Hospital reported between January 1993 and December 2014 through "Integrated Laboratory Management System (ILMS)" software.
Hyams Grading System for Olfactory Neuroblastoma Lobular Architecture Nuclear Grade Preservation Mitotic Index Pleomorphism I Present Zero None II Present Low Low III May or may not be present Moderate Moderate IV May or may not be present High High Grade Fibrillary Matrix Rosettes Necrosis I Prominent HW rosettes None II Present HW rosettes None III Low FW rosettes Rare IV Absent None Frequent Abbreviations: FW, Flexner-Wintersteiner; HW, Homer-Wright.
Olfactory neuroblastoma is an uncommon malignant neoplasm.
Squamous cell carcinoma (SCC) of the maxillary sinus was the most common malignant lesion encountered (17.6%) followed by 2 cases (5.9%) of melanoma and sinonasal lymphoma each and one case of olfactory neuroblastoma (2.9%).
* Olfactory neuroblastoma is nonepithelial and the most differentiated of the neuroectodermal tumors.
One of the characteristic radiographic findings of olfactory neuroblastoma is a dumbbell-shaped mass that extends across the cribriform plate; erosion of the cribriform plate, lamina papyracea, and/or fovea ethmoidalis may also be seen.
Olfactory neuroblastoma was the second common lesion observed in the study showing peak incidence in fifth decade unlike study done by Morita.
The tumor must be differentiated from melanoma, olfactory neuroblastoma, lymphoma, and rhabdomyosarcoma.
This was highly suggestive of Olfactory Neuroblastoma. A diagnosis of Olfactory neuroblastoma, Kadish (modified) Stage C was made.
However, there is a broad histologic differential diagnosis, which includes melanoma, rhabdomyosarcoma, lymphoma, olfactory neuroblastoma, Ewing's sarcoma, and primitive neuroectodermal tumors.
* Among all the 100 patients, 83% were histopathologically diagnosed to have nasal polyps, angiofibroma in 7%, rhinosporidiosis in 2%, septal angioma in 2%.One case each of capillary haemangioma, squamous cell carcinoma, angiosarcoma, transitional cell carcinoma, nasopharyngeal carcinoma, olfactory neuroblastoma was present.