Case History
A 52-year-old male presents with an epistaxis and nasal obstruction. Imaging shows a 2.1 cm mass involving the cribriform plate of the ethmoid sinus.
What is the diagnosis?
- Neuroendocrine carcinoma
- NUT carcinoma
- Mucosal Melanoma
- Olfactory Neuroblastoma
Answer: D. Olfactory Neuroblastoma
Olfactory Neuroblastoma is a rare malignancy with a bimodal age distribution that usually involves the cribriform plate of the ethmoid sinus. It is derived from the sensory neuroepithelial olfactory cells and like the olfactory neuroepithelium contains 3 cell types: Basal cells, olfactory neurosensory cells, and sustentacular cells. The cytology slide shows loosely cohesive intermediate sized cells with fine chromatin. H & E shows round small blue cells arranged in a lobular configuration with a stroma composed of neurofibrillary material. Immunohistochemistry was positive for synaptohysin and chromogranin.