Olfactory Neuroblastoma: A 35-Year Experience and Suggested Follow-up Protocol

Objectives/Hypothesis: To validate a follow-up protocol based on the long-term outcomes and recurrence rates in patients who have undergone surgical treatment for olfactory neuroblastoma. Methods: A prospective review of all patients treated for olfactory neuroblastoma at our institution over a 35-year period. Results: Ninety-five patients were treated from 1978 to 2013, with craniofacial (65 patients) or endoscopic resection (30 patients). Duration of follow-up ranged from 1 to 309 months (mean, 88.66 months). Fifty-six patients were alive and well, and 13 were alive with recurrent disease. Twenty-one patients had died of disease, and three had died of intercurrent disease. Overall survival was 83.4% at 5 years and 76.1% at 10 years. Disease-free survival at 5 years was 80% and at 10 years was 62.8%. A Cox regression analysis showed orbital extension and intracranial involvement to be significant independent factors affecting outcome. Local and regional recurrence occurred after an average of 49 months but with a range of 3 to 233 months. Conclusions: In our series, olfactory neuroblastoma most commonly recurred within the first 4 years but can recur very late, after 19.4 years in one case. There is currently no universally accepted follow-up regime, but even late recurrence is eminently treatable. We therefore propose a protocol for lifelong follow-up with both clinical examination and serial imaging, including the neck and entire intracranial compartment.