Safety of surveillance endoscopy and EUS of the esophagus after neoadjuvant chemoradiotherapy: Results from the (pre)SANO trial.

Background and study aims: Active surveillance has been proposed for patients with esophageal cancer and a clinical complete response after neoadjuvant chemoradiotherapy (nCRT). This strategy involves repeated esophagogastroduodenoscopy (EGD) with bite-on-bite biopsies and endoscopic ultrasonography (EUS) with fine-needle aspiration (FNA) to detect tumor regrowth or residual disease. The aim of this study was to assess safety of endoscopic procedures during active surveillance. Patients and methods: A prospective multicenter cohort including patients who were treated with nCRT for esophageal cancer and who underwent EGD with bite-on-bite biopsies and/or EUS (with fine-needle aspiration) was retrospectively analyzed. The primary outcome was the difference in number of serious adverse events (SAEs) in endoscopic procedures performed within vs. more than 3 months after nCRT. The secondary outcome was mechanical injury. Results: In 920 patients, 2291 endoscopic procedures were performed (57% EGD combined with EUS, 39% EGD only and 4% EUS only). Of these procedures, 819 (36%) were performed more than 3 months after nCRT in 186 patients. Two gastrointestinal bleedings were reported during endoscopic procedures performed within 3 months after nCRT. One gastrointestinal bleeding and two infections were reported after 3 months following nCRT. Frequency of SAEs before and after 3 months following completion of nCRT was not significantly different (2 vs. 3, odds ratio 2.7, 95% confidence interval 0.3-32.4, Conclusions: EGD with bite-on-bite biopsies and EUS with FNA seem to be safe during an active surveillance strategy in esophageal cancer patients after nCRT.