The Efficacy of Adjuvant FOLFOX6 for Patients With Gastric Cancer after D2 Lymphadenectomy: A Propensity Score-matched Analysis

Adjuvant 5-fluorouracil, folinic acid, and oxaliplatin (FOLFOX6) are widely used for treating resected gastric cancer in clinics in China, but only few clinical trials have investigated its efficacy. Using propensity score matching, we evaluated the efficacy of adjuvant FOLFOX6 following D2 lymphadenectomy. Patients who received adjuvant FOLFOX6 following D2 lymphadenectomy (FOLFOX6, n = 113) or D2 lymphadenectomy only (surgery-only, n = 512) between 1998 and 2007 at our center were propensity score-matched; we identified a balanced 1:2 cohort, with 96 patients in the FOLFOX6 group and 192 patients in the surgery-only group. The overall survival (OS) was estimated using the Kaplan–Meier method; factors affecting survival were identified by Cox regression models. A nomogram incorporating independent prognosticators was constructed for predicting the 3-, 5-, and 7-year OS, and bootstrap validation was performed. The median follow-up was 9.3 years, and the 7-year OS was 52.1% in the FOLFOX6 group and 43.8% in the surgery-only group (P = 0.04), with an adjusted hazard ratio of 0.69 (95% confidence interval = 0.49–0.98). A prognostic nomogram was generated with the identified significant prognosticators (adjuvant FOLFOX6, number of total harvested nodes, the interaction effect between these two variables, tumor size, T and N stage). Internal validation of the nomogram revealed good predictive abilities, with a bootstrap-corrected concordance index of 0.70. Adjuvant FOLFOX6 following D2 lymphadenectomy is associated with survival benefit in resected gastric cancer. Receiving adjuvant FOLFOX6 can be developed into a nomogram with other independent prognosticators to refine OS prediction and estimation of benefit from adjuvant FOLFOX6 for resected gastric cancer.