Prognostic ımpact of the modified Ryan tumor regression score in gastric and GEJ adenocarcinomas treated with neoadjuvant FLOT regimen.

[OBJECTIVE] This study aimed to evaluate the prognostic significance of the Modified Ryan Tumor Regression Score (TRG) in predicting overall survival (OS) and disease-free survival (DFS) among patients with locally advanced gastric and gastroesophageal junction (GEJ) adenocarcinomas treated with neoadjuvant FLOT chemotherapy (5-fluorouracil, leucovorin, oxaliplatin, and docetaxel). We aimed to evaluate whether the modified Ryan TRG independently predicts DFS and OS in a homogeneous FLOT-treated cohort.

[MATERIALS AND METHODS] Patients with locally advanced gastric or GEJ adenocarcinomas who received neoadjuvant FLOT and underwent curative surgery were retrospectively reviewed. The Modified Ryan TRG was categorized into four grades (0-3) according to the proportion of residual viable tumor cells.

[RESULTS] A total of 154 patients were included in the analysis. Among all patients, 26.6% achieved a good pathological response (TRG 0-1), 24.7% had a partial response (TRG 2), and 48.7% showed minimal or no response (TRG 3). Median DFS and OS were not reached in the TRG 0-1 group, whereas they were 16.1 and 29.9 months, respectively, in the TRG 3 group (p < 0.001). Lower TRG (0-1) independently predicted improved DFS (HR = 0.07, p < 0.001) and OS (HR = 0.10, p = 0.002).

[CONCLUSION] The Modified Ryan Tumor Regression Score represents a strong and independent prognostic indicator in patients with locally advanced gastric and GEJ adenocarcinomas treated with the FLOT regimen. Patients with low TRG (0-1) scores exhibit superior survival outcomes, while those with high TRG (3) scores may benefit from closer follow-up and intensified adjuvant strategies. Prospective studies are warranted to validate TRG-based individualized treatment approaches.