胃肠道间质瘤的临床病理形态和免疫组织化学特点

目的:研究胃肠道间质瘤(gastrointestinal stromal tumors,GISTs)的病理学特点及免疫组化特性,探讨其诊断标准和免疫组化在诊断中的价值.方法:通过光镜对GI STs进行观察,应用EnVisionTM+免疫组化染色检测CD34等系列标记物在肿瘤中的表达 .结果 :GISTs有梭形细胞和上皮样细胞两种基本细胞成份,有梭形细胞型、上皮细胞型和混合型 3种组织类型,有良性,交界性和恶性3种分化,并有单项或多项分化能力.本组45例GIST s中有良性8 例,潜在恶性12例,恶性25例.肿瘤组织Vimentin全部阳性,CD34有36例阳性(阳性率80.0%),部分病例呈现灶片状或个别细胞的肌动蛋白和/或S-100阳性.在形态上GISTs与平滑肌瘤和神经鞘瘤难以区别,应用CD34等多种免疫组化标记物是非常必要的. 结论:GISTs是消化道一组常见的间叶性肿瘤,有多种分化和形态,在诊断时需依靠免疫组化标记方可与其它非上皮性肿瘤鉴别.

A clinicopathologic and immunohistochemical study of gastrointestinal stromal tumors

Objective: To study the clinicopathologic features and immunohistochemical speciality of the gastrointestinal stromal tumors(GISTs), and explore their criterion and value of the immunohistochemical stain in the diagnosis. Methods: In addition to light microscopic observations, a series of markers were used by EnVisionTM+ method in GISTs. Results: The tumor showed two basic cell compositions with elongated spindle cells and epithelioid cells. There are three histologically features: the spindle type, epithelial type and mixture type, and three classifications: benign, borderline and malignant, and differentiations with single or multiple tissues. The group of GISTs consisted of 45 tumors: 8 cases benign, 12 borderline malignant and 25 malignant. All tumors were positive for vimentin and 36(80.0%) of these tumors showed reactivity for CD34. The partial cases were positive for Action and/or S 100 in single cell or focal areas. In morphology it was difficult for GISTs to be differentiated from leiomyomas and schwannomas. It was very necessary to use a series of immunohistochemical markers, especially CD34 antibody. Conclusion: GISTs were the most common group of mesenchymal tumors that arise in the wall of the gastrointestinal tract and express various differentiations and morphologies. It is necessary to distinguish other tumors from the nonepithelial neoplasms of gastrointestinal tract, which is dependent on immunohistochemical features.