69例胃肠道间质瘤的病理形态学及免疫组化分析

目的：研究胃肠道间质瘤（GIST）的临床病理学形态及免疫组化特征。方法：对69例GIST作了临床病理学的形态观察和免疫组织化学研究。结果：69例GIST中，良性9例（13．0％），交界性25例（36．2％），恶性35例（50．8％）；细胞类型以梭形细胞为主的有46例，伴上皮样细胞的有19例，单纯由上皮样细胞组成的有4例。免疫组织化学特征：65例（94．2％）CD117（C-kit）胞质强阳性，58例（84．1％）CD34阳性，16例（23．2％）S－100蛋白呈局灶或散在阳性；14例（20．3％）SMA呈局灶阳性，仅3例（4．3％）desmin阳性。结论：胃肠道间质瘤恶性发生率较高（50．8％），有较为独特的组织学形态，免疫组织化学CD117敏感性强，特异性高，是胃肠道间质瘤可靠的标记物；CD34表达率较高，可作为诊断的的参考指标。

Gastrointestinal Stromal Tumors :A Morphologic and Immunohistochemical Study of 69 Cases

Objective:To investigate the morphological and immunohistochemical characteristics of gastrointestinal stromal tumors(GIST).Methods:69 cases of GISTs were investigated with clinicopathological observation and immunohistochemical analysis.Results:Of 69 cases,9 (13.0%)were benign,25 (36.2%)were bordline and 35(50.8%) were malignant.According to the cell types,46 cases were spindle cells, 19 cases were both spindle and epithelioid cells and 4 cases were epithelioid cells only.Immunohistochemical results showed as follows,65 cases (94.2%) were stained strongly with CD117;58(84.1%)were postive to CD34;16(23.2%)cases were stained with the S 100 protein,focally and weakly;14 cases(20.3%) were locally postive to SMA;only 3 cases(4.3%) were postive to desmin.Conclusion:Most GIST were malignant. CD117 is a useful marker to recognize GIST.The rate of CD34 positivity is higher in GIST and this may be helpful to the diagnosis.