Real world evidence of survival in locally advanced esophago-gastric cancers treated with perioperative chemotherapy vs preoperative chemoradiotherapy.

e16162 Background: Upper GI (UGI) adenocarcinoma - esophageal, gastroesophageal junction (GEJ), and gastric - are among the leading causes of cancer death globally and in the US. Among patients (pts) with localized disease, the 5-year survival rate is low at 30%. Based on the FLOT4 trial, perioperative FLOT chemotherapy (CT) was established as the standard of care for resectable gastric and GEJ adenocarcinoma. In the recently published ESOPEC trial, perioperative CT with FLOT led to improved survival compared with preoperative chemoradiotherapy (CRT) among patients with resectable esophageal adenocarcinoma. This study aims to evaluate the real-world treatment patterns and outcomes in patients with localized UGI adenocarcinoma treated with these different modalities. Methods: Pts diagnosed with locally advanced UGI adenocarcinoma in 2004-2021 were identified in the National Cancer Database (NCDB). Inclusion criteria included age 18 years or older, AJCC Stage Ib-III (cT1b-4,N0-1,M0), pre- or perioperative treatment with chemotherapy or radiation or combination. Exclusion criteria were histology not adenocarcinoma, or missing treatment data. Four treatment groups were created (Table 1). Kaplan-Meier analysis and multivariate Cox regression were used to compare survival outcomes. All analyses were conducted using SAS 9.4 (SAS Institute Inc., Cary, NC). Results: Among the 840 patients in the analysis, mean age at diagnosis was 62 years, 85% were white, and 77% males. The median follow up was 118.6, 65.5, 43.2, and 38 months for Group 1, 2, 3, and 4 respectively. After adjustment for age, sex, race, Charles-Deyo Comorbidity score, compared with pts who received preoperative CRT only (group 4), preop CT (group 1) and perioperative CT (group 2) were associated with statistically significant improved OS; Group 1 vs. 4 (HR [95% CI] = 0.56 (0.40, 0.79); p = 0.001) and Group 2 vs. 4 (HR = 0.55 (0.36, 0.83); p = 0.005). There was no statistically significant OS difference between preop CT followed by CRT (Group 3) and preop CRT only (HR 0.87 (0.63, 1.19, p = 0.384)). Conclusions: These real-world data from the largest cohort of localized UGI adenocarcinoma support findings from recent clinical trials showing the superiority of peri- or preop chemotherapy over CRT. Overall survival among patients with localized UGI adenocarcinoma treated with different modalities. Group No. of pts Event Censored Median follow up, months (95% CI) 5 yr-Survival Rate (95% CI) 1 (At least 4 months of preoperative CT only) 304 130 (43%) 174 (57%) 118.6 (61.3, 145) 48.8% (39.7%, 57.3%) 2 (Perioperative CT only) 98 43 (44%) 55 (56%) 65.5 (54.6, NA) 45.4% (31.9%, 57.9%) 3 (Preoperative CT followed by CRT) 380 238 (63%) 142 (37%) 43.2 (34.3, 54.3) 24.5% (18.4%, 31.1%) 4 (Preoperative CRT only) 58 47 (81%) 11 (19%) 38 (22.2, 73.3) 26.8% (16.0%, 38.7%)