Clinicopathological Features and Surgical Management of Gastrointestinal Stromal Tumors: State-of-the-Art

Excerpt

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors, thought to arise from the interstitial cells of Cajal. Almost all GISTs have mutations in the oncogenic tyrosine protein kinase KIT or platelet-derived growth factor receptor-alfa. GISTs are mostly formed in the stomach and the small intestine. GISTs are often asymptomatic, but when symptoms occur, they most commonly include gastrointestinal bleeding, early satiety, and abdominal pain. These tumors do not have specific endoscopic or radiological features. The treatment for confirmed GISTs is surgery if the lesion is resectable with no metastases, or therapy with tyrosine kinase inhibitors if the lesion is unresectable, metastatic, or recurrent. The prognostic factors are tumor location, tumor size, mitotic index, and type of mutation. All surgical techniques can be performed laparoscopically using five trocars for wedge resection, subtotal gastrectomy or total gastrectomy based on tumor location. In case of intragastric resection with a single port under laparoscopic control, intraoperative endoscopy is used to identify the exact location of the lesion, and to guide single port device placement inside the stomach after gastrotomy. During subtotal and total gastrectomy, indocyanine green fluorescence angiography is performed to assess the vascular supply. This chapter discusses the clinicopathological features of gastric GISTs and describes the standard minimally invasive management techniques.