Long-term outcomes of locally advanced and borderline resectable esthesioneuroblastoma and sinonasal tumor with neuroendocrine differentiation treated with neoadjuvant chemotherapy

Background: Sinonasal tumors are a rare group of neoplasms with limited data available regarding their treatment. Objectives: To estimate the 5 year outcomes and late adverse events of locally advanced sinonasal tumors treated with neoadjuvant therapy (NACT) followed by local therapy. Methods: Twenty-five patients with locally advanced esthesioneuroblastoma or sinonasal neuroendocrine tumors treated between August 2010 and August 2014 with NACT followed by local therapy were selected. The 5-year outcome and late adverse events (CTCAE version 4.02) were noted. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method. COX regression analysis was used to identify factors impacting PFS and OS. Results: The median follow-up was 5.15 years. The 5-year PFS in the esthesioneuroblastoma cohort and in the sinonasal neuroendocrine carcinoma (SNEC) cohort was 63.5% (95% confidence interval [CI]: 28.9–84.7) and 34.6% (95% CI: 10.1–61.1), respectively (P = 0.1). The only factor impacting PFS on multivariate analysis was a response to NACT (P = 0.033). The 5-year OS in the esthesioneuroblastoma cohort and in the SNEC cohort was 91.7% (95% CI: 53.9–98.9) and 46.2% (95% CI: 19.2–69.6), respectively (P = 0.024). Any grade late adverse events were seen in 20 patients (80%). Metabolic late adverse events were seen in 19 patients (76%). Conclusion: NACT in advanced sinonasal cancers is associated with an improvement in 5-year outcomes. However, late side effects, especially metabolic, are seen in these patients and should be evaluated during follow-up.