Surgical management of gastrointestinal stromal tumors: analysis of outcome with respect to surgical margins and technique.

This report reviews the methods and goals of treatment of gastrointestinal stromal tumor (GIST), the most common mesenchymal tumor of the gastrointestinal tract. GISTs express CD117, which serves as an immunohistochemical diagnostic marker. Surgical excision is the definitive treatment for all primary GISTs greater than 2 cm without evidence of peritoneal seeding or metastasis. Preoperative or intraoperative biopsy is not indicated except when the differential diagnosis includes another type of malignancy. Resection may be performed by traditional open surgery or by laparoscopic or laparoscopy-assisted procedures. Regardless of the approach, oncological precautions must be strictly observed. Tumor disruption is to be avoided at all costs; tumor enucleation leaves a tumor-seeded pseudocapsule behind and is considered insufficient. Because GISTs rarely metastasize through the lymphatics, routine lymphadenectomy is not indicated. The importance of achieving negative microscopic margins is controversial, although patients who undergo incomplete microscopic resection may be at greater risk of locoregional recurrence. Other factors, such as tumor grade and size, may play a more significant role in predicting recurrence. Cases of advanced disease or involvement of adjacent structures should be evaluated on an individual basis by a multidisciplinary team.