Olfactory Neuroblastoma (Esthesioneuroblastoma) following Retro-Orbital Irradiation for Graves' Ophthalmopathy

Background: Olfactory neuroblastoma is a rare malignancy of the nasal cavity. Methods: We describe a case of radiation-induced olfactory neuroblastoma in a patient with a history of radiation for Graves' ophthalmopathy. We also reviewed the literature and found four other cases of radiation-induced olfactory neuroblastoma reported since 2000, suggesting prior radiotherapy as one risk factor for this disease. Results: We treated the patient with multimodality treatment consisting of surgery, radiotherapy and chemotherapy (6 cycles of cisplatin/ etoposide). Despite the previously irradiation, treatment was well tolerated without excessive short or long term radiation toxicity. The patient remains in long term remission with no evidence of loco-regional recurrence or systemic metastasis after 12 years of follow-up. Conclusions: Prior radiotherapy appears to be a risk factor in a handful of cases of this rare malignancy. Although the literature is limited for radiation-related olfactory neuroblastoma, outcomes appear generally poorer for this group but highly variable. With careful patient selection, aggressive multi-modality therapy including post-operative radiotherapy may be feasible.