Roux-en-Y gastric bypass has transformed obesity management, yet concerns remain regarding cancer risk in the excluded stomach, where endoscopic access is limited. In this large population-based cohort study from Denmark, Finland, and Sweden including 109,097 bariatric procedures (82,394 gastric bypass), 46 patients developed gastric non-cardia adenocarcinoma over up to 44 years of follow-up. Gastric bypass was associated with an increased risk of non-cardia adenocarcinoma 10–44 years postoperatively compared with other bariatric procedures (HR 4.0; 95% CI 1.2–13.7) and the general population (SIR 2.5; 95% CI 1.4–5.0), although no excess risk was observed within the first 1–9 years.
Among affected patients, gastrectomy rates appeared lower and all-cause mortality higher after gastric bypass, suggesting possible delayed detection. Importantly, despite the relative risk increase, absolute…
