Impact of preoperative tumor rupture timing on gastrointestinal stromal tumor prognosis: a retrospective multicentric cohort study.

Background: A gastrointestinal stromal tumor rupture entails a high risk of recurrence even after curative surgery. However, the definition of rupture is unclear, and the question of whether patients with a minor rupture should be treated with adjuvant imatinib remains controversial.

Methods: The present, retrospective, multicentric study enrolled 57 patients with gastrointestinal stromal tumor with a minor/major tumor rupture, of whom 46 were finally found to be eligible for analysis. Tumor ruptures were subclassified by their degree, timing and cause. Multivariate analysis was performed to identify the risk factors of all types of recurrence as well as of peritoneal recurrence only.

Results: The study cohort included minor (n = 24), intraoperative (n = 19) and iatrogenic (n = 20) ruptures besides the typical types (major, preoperative and spontaneous). All intraoperative ruptures were iatrogenic. In total, 27 patients (58.7%) had a recurrence in the peritoneum (n = 17) and/or the liver (n = 13) during a median follow-up period of 5.8 years, but no recurrence was observed in patients with tumor rupture as a single, high-risk factor. Multivariate analysis found the timing of tumor rupture to be an independent risk factor of poor recurrence-free survival (hazard ratio: 2.37; 95% confidence interval: 1.02-5.49; P = 0.045).

Conclusions: Preoperative tumor rupture in patients with a ruptured gastrointestinal stromal tumor was associated with poor recurrence-free survival. Our results suggested that a distinction should be made between preoperative and intraoperative tumor ruptures when considering the indications for adjuvant imatinib therapy for gastrointestinal stromal tumor patients with tumor rupture as a single, high-risk factor of recurrence.