Impact of Delay in Adjuvant Chemoradiation on Survival in Resected Gastric Cancer

BackgroundAdjuvant chemo(radio)therapy is known to improve survival in resected gastric cancer. However, there is scant data on the effect of delay in start of adjuvant treatment (AT) after surgery, and guidelines regarding optimal timing are mostly empirical.MethodsIn this ambispective analysis, we evaluated the survival outcome of patients who underwent upfront curative intent radical gastrectomy followed by AT at our center from 2002 through 2019. Cox proportional hazards model was used to identify predictors of recurrence-free survival (RFS) and overall survival (OS).ResultsTwo-hundred and thirty patients (median age 53 years) with stage I-III carcinoma stomach were included. Seventy-six percent patients underwent D2 lymphadenectomy; 12% received adjuvant chemotherapy alone while 88% received chemoradiotherapy. AT was initiated at a median 42 days after surgery; 17% started within 4 weeks, 55% between 4–8 weeks, and 28% after 8 weeks. Five-year RFS and OS for full cohort were 42.3±4.2% and 63.2±4.4%, respectively. On multivariate analysis, disease stage, ECOG performance status and time to AT emerged as significant predictors of RFS and OS while extent of lymphadenectomy, number of resected lymph nodes and margin positivity did not. Initiation of AT after 8 weeks was associated with significantly worse 5-year RFS (HR 2.28; 95% CI, 1.29–4.04; p=0.005) and OS (HR 2.65; 95% CI, 1.27–5.52; p=0.010).ConclusionsDelaying AT beyond 8 weeks after radical gastrectomy may be detrimental to disease recurrence and survival in patients with gastric cancer. If patients have adequately recovered, AT should preferably be initiated within 8 weeks of surgery.