PS02.114: CLINICAL SIGNIFICANCE OF PREOPERATIVE CHEMORADIOTHERAPY FOR RESECTABLE ESOPHAGEAL CANCER PATIENTS USING PROPENSITY SCORE

Abstract

Abstract Background Preoperative chemoradiotherapy(CRT) for advanced resectable esophageal cancer patients is controversial in Japan, and it is different from other countries. We examine the clinical significance of it using propensity score(PS). Methods 142 patients in resectable cStageII/III/IV(TNM 6th edition) esophageal cancer patients were studied. There were 55 preoperative CRT cases (Group A), 87 patients with surgery alone(Group B). The survival was analyzed between the two groups. PS was calculated by Logistic analysis and the background factor was adjusted by the PS matching and IPTW(Inverse probability of treatment weighting) method for the preoperative CRT (Group A) vs surgery alone group (GroupB), Cox model was used to analyzed the prognostic factors. Results 1, Unmatched situation: In OS(Overall survival), no difference was found between the two groups. In DFS(Disease free survival), the prognosis of group A was better than that of group B (5 years DFS: 52.2% vs 34.55%, P < 0.05). 2, After PS matching: OS, GroupA was tended to be better(P = 0.097). DFS: the prognosis of the Group A was better (5 years DFS: 57.2 vs 28.1%, P < 0.01). With Cox analysis, the presence or absence of preoperative CRT was a significant prognostic factor. 3, After IPTW: Prognosis of group A in both OS and DFS was better (5 years OS: 77.25 vs 41.13%, P < 0.05, 5 years DFS: 76.7 vs 32.14%, P < 0.01). In Cox analysis, preoperative CRT and TNM stages were independent prognostic factors. Conclusion 1, Preoperative CRT for resectable advanced esophageal cancer is a recommended treatment by analyzing the PS. 2, IPTW and PS matching are different methods for evaluating PS, and since there is a possibility that different results may be occurred when evaluated between two groups by PS, the evaluation of it should be done more carefully. Disclosure All authors have declared no conflicts of interest.