OBJECTIVETo investigate the clinical pathological characteristics and prognosis of gastrointestinal stromal tumors (GISTs).

METHODSOne hundred and seven cases, admitted to our hospital from Apr. 1996 to Oct. 2005, were detected by Envision immunohistochemical method and diagnosed as GISTs. Their pathological features, immunohistochemical phenotypes, clinical manifestations and imaging findings were analyzed.

RESULTSOf the 107 GISTs, 107 cases were positive for vimentin (107/107, 100%), 107 cases were positive for CD117 (107/107, 100%), 89 cases were positive for CD34 (89/107, 83.2%), 14 cases were positive for SMA (14/107, 13.1%), 10 cases were positive for desmin (10/107, 9.3%), 22 cases were positive for S-100 (22/87, 20.6%) and 15 cases were positive for NSE (15/107, 14.0%). Among all the GISTs, 73 cases occurred in stomach (68.2%), 28 in small intestine (26.2%), 1 in colon (0.9%) and 5 occurred in other position including mesentery, omentum, and retroperitoneum (4.7%). Fifteen cases were diagnosed as very low grade (14.0%), 25 cases as low grade (23.4%), 33 cases as low malignancy (30.8%) and 34 cases as high malignancy (31.8%). The follow-up was obtained successfully in 89 cases (83.2%). Fourteen cases (13.1%) were confirmed to have recurrences or metastases by review and medical records.

CONCLUSIONSThe diagnosis of GIST depends on pathological observation and immunohistochemical study. CD117 is a sensitive marker for the diagnosis of GIST. Surgical resection is the choice for treating GIST. Extended resection, even combined resection of involved organs, is required for malignant GIST.