Laparoscopic sleeve gastrectomy performed in a morbidly obese patient with gastrointestinal stromal tumor: a case report and literature review

Background Gastrointestinal stromal tumor (GIST) is the most frequent submucosal tumor, and with advancements of diagnostic modalities, the incidence of GIST cases diagnosed have increased. Similarly, prevalence of morbid obesity has also rapidly increased over the past decade. Notably, the incidence of GIST in obese patients was reported to be more frequent as compared to the general population. Despite local resection being the first choice for GIST treatment, extensive surgery should also be considered depending on the tumor size and location. Laparoscopic sleeve gastrectomy (LSG), the most popular bariatric procedure, could also be a concomitant treatment option for both morbid obesity and GIST when the tumor is contained within LSG the excision range. There are, however, few reports about LSG planned for GIST preoperatively. Case presentation A morbidly obese 46-year-old Japanese male (body weight of 105.4 kg, body mass index (BMI) of 36.6 kg/m 2 ) was diagnosed with an intramural GIST in the gastric fundus. Because of his extreme visceral fat dominated obesity (visceral fat area of 386 cm 2 ), in addition to the size and location of the tumor, we determined that it would be difficult to perform local resection. We planned LSG as a concomitant treatment for both GIST and morbid obesity. After the preoperative examination and 6 months of weight control, the patient lost enough weight to undergo LSG safely. Keeping enough distance away from the tumor, which we observed with an endoscope, we performed LSG to successfully resect the tumor. The patient was discharged uneventfully. Weight loss was successful as his BMI was 21.0 kg/m 2 at 3 months post-surgery. Conclusion We successfully performed LSG in a morbidly obese patient with a large GIST. This is the largest GIST concomitantly resected with LSG reported within current literature.