Does Adjuvant Chemoradiotherapy Improve the Prognosis of Gastric Cancer After an R1 Resection? Results from a Dutch Cohort Study

Objective The aim of this study was to investigate the impact of adjuvant chemoradiotherapy (CRT) on survival of non-metastatic gastric cancer patients who had undergone an R1 resection. Methods We compared the survival of patients after an R1 gastric cancer resection from the population-based Netherlands Cancer Registry who did not receive adjuvant CRT (no-CRT group) with the survival of resected patients who had been treated with adjuvant CRT (CRT group) at our institute. Patients who had a resection between 2002 and 2011 were included. CRT consisted of radiotherapy (45 Gy) combined with concurrent cisplatin- or 5-fluorouracil-based chemotherapy. The impact of CRT treatment on overall survival was assessed using multivariable Cox regression and stratified propensity score analysis. Results A series of 409 gastric cancer patients who had undergone an R1 resection were studied (no-CRT, N = 369; CRT, N = 40). In the no-CRT group, median age was higher (70 vs. 57 years; p