A guide for the diagnosis and management of gastrointestinal stromal cell tumors

Gastrointestinal stromal cell tumors (GISTs) always have a degree of malignant potential, and, increasingly, they are diagnosed only on routine endoscopy. Sepe and Brugge provide a gastroenterologist's guide for GIST diagnosis and assessment of malignant potential. The authors of this Review also propose an algorithm for the treatment of localized GISTs that is especially useful for the management of incidentally diagnosed tumors. Gastrointestinal stromal cell tumors (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal tract and are frequently detected on routine endoscopy. Although only ∼10–30% of GISTs are clinically malignant, all may have some degree of malignant potential. Preoperative determination of malignancy risk can be estimated from tumor size and location, but reliable histopathologic criteria are not currently available. Given such biological uncertainty, accurate diagnosis is essential to differentiate these lesions from other truly benign, subepithelial tumors. Endoscopic ultrasound-guided fine-needle aspiration has emerged as an important procedure to secure a tissue diagnosis of a GIST. When encountering GISTs, gastroenterologists are faced with challenging management decisions, especially in the face of small, incidentally discovered lesions. The majority of localized GISTs are managed via surgical resection, although a select few may be observed using serial endoscopic ultrasound examinations. This Review provides a general overview of GISTs, with an emphasis on their endoscopic diagnosis, the management of localized disease, and the management of incidentally discovered GISTs. Key Points Gastrointestinal stromal cell tumors are the most common mesenchymal neoplasm of the gastrointestinal tract and are frequently discovered on routine endoscopy Approximately 10–30% of gastrointestinal stromal cell tumors are clinically malignant, but all such tumors may have some malignant potential Preoperative malignancy risk can be estimated from tumor size and location, but a set of reliable histologic criteria do not currently exist The diagnosis of a gastrointestinal stromal cell tumor can be suggested by esophagogastroduodenoscopy or endoscopic ultrasonography, but definitive diagnosis requires tissue acquisition via endoscopic ultrasound-guided fine-needle aspiration Complete surgical resection is the mainstay of treatment for localized disease, although, for a small subset of patients, surveillance via serial endoscopic ultr