Predictive Significance of Ki-67 and Platelet Lymphocyte Ratio in Patients with Gastric Cancer Receiving Neoadjuvant FLOT Chemotherapy

Objective: We aimed to determine the predictive significance of Ki-67 and platelet lymphocyte ratio (PLR) in patients with gastric cancer (GC), who received fluorouracil, leucovorin, oxaliplatin, docetaxel (FLOT) as neoadjuvant chemotherapy (NAC). Study Design: Descriptive study. Place and Duration of Study: Department of Medical Oncology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey from March 2016 to January 2020. Methodology: Seventy-five patients with GC, who received FLOT treatment as NAC were included in the study. Ki-67 and PLR, which were examined pre-NAC and aft-NAC, were recorded. Associations between clinical-histopathological parameters with disease-free survival (DFS) and overall survival (OS) were analysed using Kaplan-Meier curves. Cox-regression analysis was used to assess their prognostic values. Results: There was a statistically significant difference between pre-NAC and aft-NAC Ki-67, and aft-NAC PLR values between groups with complete response, partial response, and stable disease aft-NAC (p: 0.023, p: <0.001; and p: 0.001, respectively). When the patients were grouped according to the pre-NAC and aft-NAC Ki-67 changes, a significant difference was found in terms of OS (p < 0.001). High pre-NAC and high aft-NAC Ki-67 were associated with shorter DFS and OS (p: 0.042, p: 0.049; p: 0.027, and p: 0.001, respectively). The high pre-NAC PLR was associated with shorter OS, while the high aft-NAC PLR was associated with shorter DFS (p: 0.018, and p: 0.001, respectively). In multivariate analysis, aft-NAC Ki-67 was found to be an independent prognostic factor for OS. Conclusion: Ki-67 and PLR have predictive significance in GC patients treated with neoadjuvant FLOT. Ki-67 is an independent prognostic marker for OS in gastric cancer.