Clinicopathologic study of 42 cases gastrointestinal stromal tumor

Objective:To investigate the pathological features of gastrointestinal stromal tumor(GIST).Methods:Light microscopy was used to study the morphologic characteristics of 42 cases of GIST.The expression of CD117,CD34,SMA,S-100 protein were detected in all cases with S-P immunohistochemical method.Results:The histological spectrum included interlacing fascicles,diffuse sheets,storiform and palisading pattern,especially the special formation cell cluster was observed.The tumor cells of GIST had degree of cytoplasmic eosinophilia than classic leiomyomas.The tumor cells of GIST were spindle,epithelioid or both in different proportion.The positivity of CD117 and CD34 were 92.9% and 76.2%.Conclusion:GISTs are the most common mesenchymal tumors in gastrointestinal tract and have specific pathological characteristics.The expressions of CD117 and CD34 are the most useful for the diagnosis of GIST.