Incidental Gastrointestinal Stromal Tumors (GIST) During Laparoscopic Sleeve Gastrectomy Procedures: a Retrospective Study

Abstract

Purpose: Gastrointestinal stromal tumors (GIST) are the most frequently occurring form of mesenchymal tumors in the gastrointestinal tract. Laparoscopic sleeve gastrectomy (LSG) is a commonly performed bariatric operation in which a portion of the gastric body and fundus is removed and sent for pathological examination. Increasingly, bariatric surgeons have incidentally identified neoplasms in the excised portion of the stomach. The aim of this study is to explore the incidence of GIST in obese patients undergoing LSG.

Material and methods: This is a single-center, single-surgeon retrospective case series which included 305 obese patients who underwent LSG. All excised stomach specimens were sent for pathologic analysis.. In the case of pathologically verified GIST (n = 6; 1.97%), detailed analysis was performed.

Results: In 305 LSG procedures, six cases of GIST (1.97%) were identified. The tumors were measured between 1 and 7 mm and were all low grade with negative resection margins. The mean BMI was 46.38 ± 3.94 kg/m² (range: 41.61-51.77). The mean age at time of surgery was 55.33 ± 12.9 years (range: 37-73 years). All cases were asymptomatic and showed no evidence of metastatic disease.

Conclusion: The incidental rate of GIST in the excised portion of the stomach in our 305 obese patients who underwent LSG is 6/305 (1.97%). This adds relevant data to the overall goal of determining whether obesity is a risk factor for GIST. Radical surgical resection of these tumors with adequate disease-free margins performed on a low-grade malignancy serves as a definitive oncological treatment, especially when there is an intact pseudocapsule.

Keywords: Gastrointestinal stromal tumor; Incidental findings in bariatric surgery; Incidental gist; Mesenchymal tumor; Morbid obesity; Sleeve gastrectomy.