Abstract:

Objective  To investigate the histopathological features，immunohistochemical expression and prognostic factors of gas-trointestinal stromal tumor （GIST）. Methods Clinical and pathological data were collected from 67 patients with gastrointestinal stromal tumors. All patients underwent routine pathological and immunohistochemical examination of CD117，while CD34，S-100，dog-100， desmin staining characteristics were also analyzed. Life-table method was used to estimate overall survival and survival plot curves. COX proportional hazards model was used to analyze the prognostic factors of GSIT. Results Of all the 67 cases，41 were located at stomach，17 were in bowel，and the other 9 were in the gastrointestinal tract. The most common seen histological type were fusiform common in 52 cases，followed by 12 cases of epithelial cell type，3 cases of mixed cell type. Immunohistochemistry results：61 were CD117-positive，52 were CD34-positive，65 weredog-1-positive，28 were S-100-positive and 23 were desmin-positive. The expression of  CD117，CD34，dog-1 were higher in the digestive tract than the other that are not（P<0.05）. Multivariate analysis showed that GIST prognosis was associated with distant metastasis，Gleevec treatment and risk classification（P<0.05），but not associated with sex，age，tumor location， tumor size，and CD117 expression（P＞0.05）. Conclusions  The most common type of GIST was spindle cells and stomach is the most common occurrence site，followed by intestine. CD117，CD34，dog-1 were highly expressed in the GIST. Risk classification， metastasis and Gleevec treatment were independent prognostic factors of GIST.

Key words: Gastrointestinal stromal tumor, Immunohistochemistry, CD117, CD34, dog-1, Prognosis