Incidental GIST in Patients Undergoing Bariatric Surgery: A Systematic Review of Incidence and Management

There has been a rapid increase in prevalence of obesity, and bariatric surgery is the most effective treatment to reduce all-cause mortality. Gastrointestinal stromal tumors (GISTs) comprise approximately 1% of GI tumors and are the most commonly encountered incidental tumor at the time of bariatric surgery. They have a reported prevalence of approximately 0.5%; however, there are no established guidelines for incidental GISTs.

This study performed a systematic literature search using PubMed to identify 100 articles from 2005 to 2023 on incidental GIST tumors found during bariatric operations.

Total prevalence of GISTs was 0.54% with an average size of 7.04 mm. Management of these lesions should prioritize negative margins with the least invasive resection. Tumors able to be resected without alteration to bariatric surgery should be managed with a complete wedge resection prioritizing negative margins. In tumors where resection requires alteration to bariatric surgical plan, the decision to proceed with resection and alteration of bariatric surgical plan should be made only if previous discussions have been made with patient. Lastly, if resection of the GIST precludes the ability to perform the bariatric procedure, consideration to resect the GIST with the goal of negative margins should be prioritized with a plan to discuss future bariatric procedures after.

The goal of this paper is to remind bariatric surgeons to be aware of GISTs and provide the possible approaches to management.