[Morphological characteristics of stromal gastrointestinal tumors].

Stromal tumors are singled out from smooth muscle and neurogenic neoplasms into a special group due to differences in CD117 expression caused by mutation of c-kit gene. Out of 57 stromal tumors, 37 (64,9%) located in the stomach, 17 (29,8%) in the small intestine and 3 (5,3%) in the colon. Immunohistochemically, all the tumors expressed CD117 and vimentine. Smooth muscle actin was found in 82% tumors, S-100 protein in 75%, neuron-specific enolase in 66% cases. Malignant tumors were in 93% cases, and in 7% benign. Metastases were observed in 47.7% cases, recurrences in 14%. The liver was most frequent site of metastases (88.9%), peritoneum (51.9%). 21% patients died of progression of the underlying disease during the follow-up of 6-60 months.