Synonyms:
a.k.a. olfactory neuroblastoma a.k.a. esthesioneuroblastoma:
Diagnosis:
Suggested by MRI and confirmed by pathology (brain biopsy/resection)
Findings on Investigations:
CT: for bone erosion, homogenous mass
MRI:
- Mass beneath the cribriform plate in the nasal cavity, extending into the nasal sinus, orbit (via lamina papyrecea) or frontal lobe (via cribriform plate). Superior cystic component
- T1: hypointense
- T2: iso- or hyper-intense
- Homogenous or inhomogeneity
- Moderate enhancement
- Dumbbell shape around the cribriform plate
Pathology:
Histology:
- Small round blue cell tumor
- Arranged in nests, Homer Wright pseudorosettes (around neuritic processes) & Flexner Wintersteiner rosettes (around a lumen) may be seen.
Immunohistochemistry:
- NSE, synaptophysin & chromogranin positive. Some S100 positivity in the periphery.
- Negative for: cytokeratin, CLA, HMB45, GFAP, desmin, vimentin,
Treatment:
Treatment modalities:
- Surgical resection
- Radiation therapy
- chemotherapy