Endoscopic Evaluation of Gastrointestinal Stromal Tumors

Abstract

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors arising from the gastrointestinal tract. GISTs can occur in any segment of the gastrointestinal tract from the distal esophagus to the anus, but they are most common in the stomach. The presence of c-KIT staining is a strong and universal marker of GISTs. Approximately 70 % patients with GISTs have some clinical symptoms, including gastrointestinal bleeding, manifested as melena, hematemesis, or bright red blood per rectum. Most GISTs are incidentally detected during endoscopic examinations. Endoscopic features are usually insufficient for the diagnosis of GISTs. Endoscopic ultrasonography (EUS) has become an important diagnostic tool for the evaluation of subepithelial lesions such as GISTs. EUS-guided sampling of GISTs is the preferred technique for histological diagnosis. The capability of endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) for biopsy of GISTs is better than any other well-accepted method. The EUS-guided Tru-cut core biopsy technique provides a grossly visible sample of tissue, but it has some technical disadvantages. The curative treatment of GISTs is still complete surgical resection. However, optimal endoscopic treatment along with imatinib remains controversial. Advanced resection techniques by endoscopic devices, including endoscopic submucosal resection, endoscopic submucosal tunnel dissection, and endoscopic-laparoscopic combined approach, have been used in the treatment of GISTs.