Risk Factors for Mucosal Ulceration in Gastric Gastrointestinal Stromal Tumors (GIST)

Abstract

Background: Gastrointestinal stromal tumors (GIST) are the most common subepithelial tumors in the gastrointestinal (GI) tract and they are usually located in the stomach. To date, only a few studies have investigated the risk factors for GIST ulceration and bleeding and there have been no prior publications focused on role of Helicobacter pylori in GIST ulceration. The aim of current study was to investigate the risk factors of mucosal ulceration in gastric GISTs. Methods: A retrospective study was conducted of 130 patients with a histological diagnosis of gastric GIST, recruited from four medical centers in Israel. The following details were extracted fom each patient: patient's age and gender; tumor location, size, mitotic rate and Ki-67 index; whether or not metastases were present, the patients' international normalization ratio (INR) and the use of antiplatelets, anticoagulants or proton pump inhibitors (PPI). Results: The median age of the patients was 69 years. Approximately one third of lesions demonstrated a mucosal ulceration. Upper GI bleeding or iron deficiency anemia (77.5%) were the most common indication for endoscopy in patients found to have an ulcerated GIST at endoscopy. On univariate analysis, mucosal ulceration in gastric GIST was associated with older age, increased number of mitoses, high Ki-67 index, location in the cardia and fundus and an elevated INR. Multivariate analysis showed significant differences only for number of mitoses (OR = 1.287, 95% CI 1.054-1.57, p = 0.013). Conclusion: In this large retrospective study, the only risk factor associated with tumor ulceration in gastric GISTs was increased mitotic rate.