Scanographic features of gastrointestinal stromal tumors.

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

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

RESULTS: 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.

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