胃肠道间质瘤24例临床病理及免疫组化分析

目的：探讨胃肠道间质瘤（gastrointestinal stromal tumor，GIST）的临床病理诊断及其免疫组化表达的意义。方法：对24例GIST进行临床病理学观察；应用免疫组化二步法检测CD117、CD34、SMA、S-100等表达。结果：24例GIST发病平均年龄52．7岁；肿瘤多见于胃；主要症状为中上腹不适和黑便；瘤块平均直径为4．1cm；肿瘤主要由梭形细胞组成，部分呈上皮样细胞，梭形细胞型14例（58．3％），上皮样细胞型4例（16．6％），混合细胞型6例（25．0％）；良性5例（20．8％），交界性5例（20．8％），恶性14例（58．4％）；免疫表型：CD117阳性23例（95．8％），CD34阳性20例（83．3％）．均呈弥漫性强阳性。结论：GIST好发干中老年人，以胃部多见；瘤细胞主要为梭形细胞；多为恶性及交界性．确诊需要CD117、CD34等免疫标记物检查。

Clinicopathological and immunohistochemical features of 24 cases of gastrointestinal stromal tumor

Objective:To explore the clinieopathological and immunohistochemical characteristics of gastrointestinal stromal tumor(GIST).Methods:The clinical and pathological features of 24 cases of GIST were observed.The protein expression of CD117, CD34,SMA,and S-100,desmin,and Vimentin were detected by using En Vision Immunohistochemical method.Results:The 24 pa- tients with GIST had an average age of 52.7 years old.They were common in the stomach.The most common presenting signs and symptoms included abdominal pain and GI bleeding.The tumor diameters ranged from 0.6 to 12cm(mean 4.1cm).Microscopically, most GIST were composed of spindle cells(14 cases,58.3%),epithelioid cells(4 cases,16.6%),or mixed cells(6 cases,25.0%). The GIST were generally benign in 5 cases(20.8%),borderline in 5 eases(20.8%),and malignant in 14 cases(58.4%).In terms of immunophenotypes,about 23 GIST patients(95.8%)expressed CD117 antigen and 20 patients(83.3%)expressed CD34 antigen. They showed diffuse strong positivities.Conclusion:GIST has a peak incidence in the elderly persons.GIST often occurred in the stomach.The tumors were mainly composed of spindle cells.Most GIST were malignant and borderline.Immunohistochemical detection of CD117 and CD34 antigens is necessary for differential diagnosis.