Abstract
The article describes a classic case of olfactory neuroblastoma in a 33-year-old female patient diagnosed with «nasal cavity neoplasm (polyp?)» who was referred to the National Centre for Neurosurgery JSC from the ENT Department of the City Hospital No. 1. The first symptoms of the tumor occurred during her pregnancy. The aggressive tumor has invaded the anterior cranial fossa and spread into the right half of the ethmoid sinuses and the orbit. The tumor diagnostics was complicated by the prevalence of symptoms of a nasal cavity neoplasm. The “olfactory neuroblastoma” diagnosis was verified by clinical observations, MRI, and pathomorphological studies. Histological examination of the tumor showed a typical structure of olfactory neuroblastoma. IHC examination showed an expression of neuronal differentiation markers. The degree of malignancy was determined by Hyams grading.