Scanographic features of gastrointestinal stromal tumors

To present the scanographic features of gastrointestinal stromal tumor (GIST) and to discuss their differential diagnosis.

A retrospective study of 45 patients who underwent surgery for GIST between January 1990 and March 2006 was performed.

Patient age was 64 years on average. The most common symptoms were abdominal pain and gastrointestinal bleeding. Tumors were located in the stomach in 28 patients (body: 19, antrum: 5, fundus: 4), the small intestine in 13 (jejunum: 6, duodenum: 4, ileum: 3), the rectum in two and the small bowel mesentery in two. Computed tomography showed a large (average size: 9.2 cm, range 3.3-30 cm) exophytic extragastric lobulated mass with an associated wall thickening in 35 cases (78%). The pattern was an endoluminal polyp (average size: 3.2 cm, range 2.2-5.5 cm) in eight cases (18%). The two mesenteric stromal tumors (4%) were seen as well-delimited lobulated large masses (3 and 12 cm). The enhancement was peripheral with central hemorrhagic, necrotic and cystic areas in 37 cases (82%). Mucosal ulceration was seen in 18 cases (40%) and ascites in five (11%). Peritoneal spread and liver metastasis were demonstrated in three patients (7%). Calcification, metastatic lymphadenopthy, venous thrombosis or vascular invasion were not seen.

Scanographic features of GIST can suggest the diagnosis of GIST before surgery.