FOLFIRINOX: The best adjuvant treatment for ampullary adenocarcinoma?

e16261 Background: Ampullary adenocarcinoma is a rare cancer for which there are no standard adjuvant treatment recommendations due to the lack of randomized clinical trials. The primary aim of this analysis is to investigate the efficacy of adjuvant FOLFIRINOX treatment in patients with resected ampullary adenocarcinoma. Methods: This multicenter retrospective cohort study was conducted at 15 institutions in Turkey between August 2007 and January 2024, involving 211 patients with resected, non-metastatic ampullary adenocarcinoma receiving adjuvant chemotherapy with various chemotherapy regimens with or without chemoradiation. Clinicopathological and treatment-related parameters were recorded. Disease-free survival (DFS) and overall survival (OS) were analyzedusing Kaplan-Meier estimates. Cox proportional hazards regression was used to identify covariates associated with OS. Results: The median follow-up time was 52 months, and 116 patients (55.2%) were alive at the timeof the analysis. The median age was 61 years (32-82). mFOLFIRINOX was administered to 16.6% of the patients (n = 35). The median DFS was non-reached (NR) (NR; NR-NR) in patients treated with mFOLFIRINOX, while it was 27 (20.1-33.3) months in patients received other treatment modalities (P = 0.034). Median OS was NR in patients receiving mFOLFIRINOX treatment, while it was 51 months in patients receiving other treatments (P = 0.071). While no statistically significant results was reached, a trend toward statistical significant survival times were obtained in the FOLFIRINOX arm. After adjusted for other prognostic parameters, mFOLFIRINOX treatment was an independent statistically significant parameter for better OS (HR; 95% CI: 3.24; 1.02-10.9; P = 0.046). Conclusions: FOLFIRINOX treatment has shown efficacy in the adjuvant treatment of ampullary cancer, independent of histological subtype. Until phase trials are published, this study provides the strongest evidence of its efficacy.