Classification of GIST and other benign gastric tumors based on minimally invasive surgical strategy

Purpose: Gastrointestinal mesenchymal tumors (GMTs) include malignant, intermediate malignancy, and benign lesions. The aim is to propose a new surgical classification to guide the intraoperative minimally invasive surgical strategy in case of non-malignant GMTs less than 5 cm.

Methods: Primary endpoint is the creation of a classification regarding minimally invasive surgical technique for these tumors based on their gastric location. Secondary endpoint is to analyze the R0 rate and the postoperative morbidity and mortality rates. Tumors were classified in two groups based on their morphology (group A: exophytic, group B: transmural/intragastric). Each group is then divided based on the tumor location and consequently surgical technique used in subgroup: AI (whole stomach area) and AII (iuxta-cardial and pre-pyloric areas) both for the anterior and posterior gastric wall; BIa (greater curvature on the anterior and posterior wall), BIb (lesser curvature on the anterior wall); BII (iuxta-cardial and pre-pyloric area in the anterior and posterior wall, including the lesser curvature on the posterior wall).

Results: Forty-two patients were classified and allocated in each subgroup: 17 in AI, 2 in AII, 5 in BIa, 3 in BIb, and 15 in BII. Two postoperative Clavien-Dindo I complications (4.8%, subgroup BIa and BIb) occurred. One patient (2.4%, subgroup AI) underwent reintervention due to R0 resection.

Conclusions: This classification proved to be able to classify gastric lesions based on their morphology, location, and surgical treatment, obtaining encouraging perioperative results. Further studies with wider sample of patients are required to draw definitive conclusions.