Clinicopathological Predictors of Pathological Response and Survival in Older Patients Undergoing Perioperative FLOT Chemotherapy for Resectable Gastric and Gastroesophageal Junction Adenocarcinoma.

Background and Objectives: Evidence regarding predictors of pathological response and long-term outcomes in older patients receiving perioperative FLOT chemotherapy for resectable gastric or gastroesophageal junction cancer remains limited. We aimed to identify factors associated with pathological response and survival in patients aged ≥65 years treated with neoadjuvant FLOT. Materials and Methods: This retrospective single-center study included 86 consecutive patients (median age, 69 years; 72.1% male) aged ≥65 years with resectable gastric or gastroesophageal junction adenocarcinoma who underwent neoadjuvant FLOT chemotherapy followed by curative-intent gastrectomy. Major pathological response was defined as College of American Pathologists tumor regression grade (CAP TRG) 0-1. Logistic regression analyses were performed to identify predictors of pathological response. Disease-free survival (DFS) and overall survival (OS) were analyzed using the Kaplan-Meier method and Cox proportional hazards regression analyses. Results: Overall, 14 patients (16.3%) achieved a major pathological response. Body mass index (BMI) ≥ 25 kg/m2 (OR 5.13, p = 0.04) was independently associated with a major pathological response. During a median follow-up of 29.2 months, 39 patients (45.3%) developed recurrence and 35 (40.7%) died. ECOG performance status (ECOG PS) ≥ 1 was independently associated with both inferior DFS (HR = 2.76, p = 0.02) and OS (HR = 2.52, p = 0.045). In addition, ypN stage 2-3 (HR = 2.58, p = 0.008) was independently associated with worse DFS, whereas positive surgical margins were independently associated with worse OS (HR = 2.62, p = 0.02). Conclusions: In older patients with resectable gastric or gastroesophageal junction adenocarcinoma treated with perioperative FLOT chemotherapy, baseline BMI was independently associated with major pathological response, whereas ECOG PS and postoperative pathological factors were independently associated with survival. These findings highlight the importance of careful patient selection and individualized multimodal treatment in this population.