Surveillance and outcomes after curative resection for gastroesophageal adenocarcinoma (GEAC).

Abstract

162 Background: Although commonly performed, the benefit of routine surveillance testing (SvT) following curative resection of GEAC is undefined. We aimed to determine frequency of successful salvage therapy (SST) in patients (pts) with relapsed GEAC who were surveyed post curative therapy. Methods: Between 2011 and 2016, 210 consecutive pts with locally advanced GEAC underwent curative surgery and subsequent surveillance at Princess Margaret Cancer Center. SST was defined as any potentially curative therapy for recurrence which resulted in post-recurrence survival (PRS) two years without further relapse. Time-to-event outcomes were analyzed using Kaplan-Meier and Cox regression methods. Results: Median age was 64.1 years. Esophageal (14%), gastroesophageal junction (41%), and gastric adenocarcinomas (45%) were included. Pts received surgery alone (29%), surgery with perioperative chemotherapy (26%) or perioperative chemoradiation (45%) as primary curative therapy. At median follow-up of 33.6 months (m, range 6.0-122.4), 3- and 5-year overall survival (OS) rates were 68% (95% CI 61-75%) and 59% (95% CI 51-68%) respectively. SvT modalities included imaging (69%), endoscopy (19%), tumor markers (4%), and clinical visits only (9%). Recurrences occurred in 95 (45%) pts, 51% were surveillance-detected (SvDR), and 47% were non-SvDR. Types of recurrences included locoregional only (4%), distant (87%) or both (9%). Salvage therapy was attempted in 14 pts (7%) with SvDR and 1 with non-SvDR. In four pts with SvDR (1.9%) salvage therapy was successful with chemoradiation or surgery perioperative chemotherapy, six were unsuccessful, and 5 had immature follow-up. Compared with pts with non-SvDR, pts with SvDR had longer median OS (34.8 vs. 24.0m, p=0.03) and PRS (14.4 vs. 4.8m, p < 0.001), and similar time-to-relapse (15.6 vs. 12.0m, p = 0.67). Palliative chemotherapy was administered in 25 pts with SvDR and 18 pts with non-SvDR with similar median duration (3.5m vs. 3.3m, p=0.64). Conclusions: Following curative therapy, 96% of relapses were distant. SvT enabled SST in only 1.9% of pts, and did not extend duration of palliative chemotherapy. These data do not support the use of routine SvT in resected GEAC.