Prognostic significance of tumor regression grade for patients with esophageal squamous cell carcinoma after neoadjuvant chemotherapy followed by surgery

Background and objectivesTo clarify prognostic factors for the patients with esophageal squamous cell carcinoma (ESCC) through an assessment of surgically resected specimens modified by neoadjuvant chemotherapy (nCT). MethodsWe retrospectively reviewed the clinicopathological data of 143 consecutive patients with ESCC who underwent nCT followed by surgery between 2008 and 2012 at our institution and conducted survival analysis. The tumor regression grade (TRG) was classified based on the proportion of residual tumor cells in the area where the tumor was thought to have existed before nCT as follows: Grade 0 (no therapeutic effect), Grade 1a (residual tumor cells 2/3), Grade 1b (1/3 residual tumor cells <2/3), Grade 2 (residual tumor cells <1/3), and Grade 3 (no residual tumor). ResultsThe 3-year OS and RFS of patients with tumor regression grade 0/1a/1b-3 were 53.6%/73.3%/88.6% and 37.7%/60.5%/83.8%, respectively. A multivariate analysis demonstrated that TRG was an independent predictor of OS (TRG 1a-3: HR, 0.46; 95%CI, 0.23-0.89), in addition to venous invasion, and of RFS (TRG 1a-3: HR, 0.49; 95%CI, 0.28-0.84), in addition to ypT factor, and venous invasion. ConclusionsTRG is a critical prognostic factor in patients with ESCC who had undergone nCT followed by surgery. J. Surg. Oncol. 2016;113:390-396. (c) 2016 Wiley Periodicals, Inc.