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

Abstract

e18507 Background: Sinonasal tumors are a rare subgroup of head and neck cancers. Locally advanced esthesioneuroblastoma and sinonasal neuroendocrine tumors (SNEC) are treated with a multidisciplinary approach with combination of surgery followed by adjuvant radiation or chemo radiation; but have unsatisfactory outcomes. Hence we devised the approach of administering neoadjuvant chemotherapy (platinum and etoposide) followed by surgery and adjuvant chemoradiation. This approach had the advantage of improved response rates, orbital preservation and improvement in short term outcomes. The present analysis was done to estimate the 5 year outcomes and late adverse events of locally advanced sinonasal tumors treated with induction chemotherapy followed by local therapy. Methods: Twenty five patients with locally advanced esthesioneuroblastoma or SNEC treated between August 2010 to August 2014 with induction chemotherapy followed by local therapy were selected. The 5 year outcomes 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 esthesioneuroblastoma cohort and in SNEC cohort was 63.5% (95%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 response to neoadjuvant chemotherapy (p = 0.033). The 5 year OS in esthesioneuroblastoma cohort and in SNEC cohort were 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 event was seen in 20 patients (80%). Metabolic late adverse events were seen in 19 patients (76%). Conclusions: Neoadjuvant chemotherapy in advanced sinonasal cancers is associated with improvement in 5 year outcomes. However late side effects especially metabolic are seen in these patients and should be evaluated during follow up. Keywords: Sinonasal; Adverse event; Esthesioneuroblastoma; SNEC; Induction; Neoadjuvant [Table: see text]