257 CHEMORADIOTHERAPY FOLLOWED BY ACTIVE SURVEILLANCE VERSUS SURGERY FOR ESOPHAGEAL CANCER: A SYSTEMATIC REVIEW AND INDIVIDUAL PATIENT DATA META-ANALYSIS

Abstract Up to 50% of patients with esophageal cancer have a pathologically complete response after neoadjuvant chemoradiotherapy (nCRT) plus surgery. An active surveillance strategy may be feasible in patients with a complete clinical response (cCR) after nCRT. The aim of this study was to perform a meta-analysis using data of individual patients that underwent active surveillance with surgery for recurrent disease versus standard surgery after nCRT. Methods A systematic search was performed in Embase, Medline, Web of Science, Scopus and Cochrane from inception to February 2020. Studies were sought that reported on overall survival and recurrence rates in patients with cCR after nCRT that underwent active surveillance versus standard surgery. Authors were contacted to supply individual patient data. Pooled hazard ratio (HR) comparing survival outcomes and distant dissemination rates (DDR) between patients with cCR undergoing active surveillance or standard surgery were estimated using a random-effect meta-analysis. Cumulative incidence of locoregional recurrences in active surveillance were assessed using a Cox Frailty model. Results Seven studies including 788 patients (256 active surveillance and 532 surgery) were identified. All authors provided anonymized patient data. Pooled two- and five-year overall-survival was 75% and 58% for active surveillance and 76% and 60% for standard surgery with a pooled HR of 1.04 (95%CI:0.73–1.49) (Figure 1). Two-years DDR was 18% and 19% for active surveillance and standard surgery, respectively (HR 1.10,95%CI:0.75–1.63). Locoregional recurrence rate necessitating esophagectomy in patients undergoing active surveillance was 24% at one year, 33% at two years and 38% at five years. Active surveillance patients undergoing postponed surgery had R0 in 91% of cases. Conclusion Overall survival is comparable in patients undergoing active surveillance with postponed surgery compared to standard surgery after neoadjuvant chemoradiation. Distant dissemination rate is also comparable between both groups. During active surveillance, local regrowths developing after two years are rare. Although these data support an active surveillance strategy, randomized trials have to be completed before an active surveillance strategy can be actively proposed to patients with esophageal cancer.