Role of cytoreductive surgery in the management of peritoneal metastases for gastrointestinal stromal tumors.

Peritoneal metastases represent the second most frequent site of dissemination in gastrointestinal stromal tumors (GIST), after the liver. Although associated with a worse prognosis than hepatic metastases, survival outcomes in peritoneal GISTosis are superior to those seen in peritoneal dissemination of other sarcomas or epithelial tumors. First-line treatment should always consist of tyrosine kinase inhibitors (TKIs), based on molecular profiling. In patients who achieve response, cytoreductive surgery may be considered aiming for complete macroscopic resection and improved oncologic outcomes. Evidence from large retrospective series supports this strategy, with reported 5-year overall survival rates of up to 80% and disease-free survival rates of approximately 30-35% in carefully selected cases. Conversely, surgery offers limited benefit in progressive disease. Therefore, surgical intervention should be performed between 6 and 12 months of TKI therapy, once tumor biology has been assessed. Decision-making must occur within multidisciplinary teams at experienced centers, integrating oncologic response, resectability, and patient condition to guide individualized treatment.