上皮膜抗原表达与胸腺瘤侵袭性的相关性分析

ANALYSIS ON THE RELATIONSHIP BETWEEN EMA EXPRESSION AND AGGRESSION OF THYMOMA

目的 采用免疫组织化学法对５１ 例胸腺瘤细胞中上皮膜抗原（ＥＭＡ） 的表达进行了研究。 方法 ＬＳＡＢ法，Ｍａｓａｏｋａ′ｓ 临床分期，ＭＭ病理分类（Ａ组：非侵袭性胸腺瘤，Ｂ组：侵袭性胸腺瘤，Ｃ组：胸腺癌）。 结果 Ａ组：２３ 例，Ｂ组：２１ 例，Ｃ组：７ 例；ＥＭＡ表达阳性细胞大多为上皮样分化的瘤细胞。ＥＭＡ表达程度：①阴性１９ 例；②低度表达２２ 例；③中度表达５ 例；④高度表达５ 例。ＥＭＡ在侵袭性胸腺瘤和胸腺癌中表达较强。我们还观察到在有包膜浸润或包膜虽完整但细胞生长较活跃者，包膜下瘤细胞中常可见到ＥＭＡ表达；在恶性胸腺瘤或胸腺癌中瘤细胞普遍有较强的ＥＭＡ表达。统计学分析：χ２ ＝２８－１３ ，Ｐ＜ ０－０１，Ｃ＝０－５３，提示ＥＭＡ表达与胸腺瘤的良恶性有相关性。 结论 胸腺瘤细胞中ＥＭＡ的表达程度，是反映其侵袭潜能的标志之一，可作为病理诊断的重要参考指标。

PURPOSE Using immunohistochemistry method,the expression of epithelial membrane antigen(EMA) was studied in 51 cases of thymoma.METHODS labeling streptavidin biotin (LSAB) method,Masaoka′s clinical stages and M M pathological classification ｛Gruop A:non aggressive thymoma[medullary,mixed,cortical predominant and cortical(no invasion)type].Group B:aggressive thymoma [cortical (with invasion),malignant thymoma].Group C:thymic carcinoma (squamous,carcinoid and other)｝.RESULTS Group A 23 cases,Group B 21 cases,Group C 7 cases.Expression of EMA:negative 19 cases;low expression 22cases;moderate expression 5 cases; high expression 5 cases.In the cases studied most of positive cells of EMA expression were epithelioid differentiated neoplasm cells.EMA were highly expressed in aggressive thymoma and thymic carcinoma.We also observed that EMA expressions in neoplasm cell were often seen in the inside of capsulae that were aggressive or complete but with active cell proliferation.Statistical analysis:χ 2=28 13, P <0 01,C=0 53,suggesting that there was a relationship between expression of EMA and malignancy of thymoma.CONCLUSIONS EMA were often expressed in malignant thymoma or thymic carcinoma;the extent of EMA expression is a mark of aggressive potentiality in thymoma,which may serve as an important consultive index in pathological diagnosis. Heterogeneity of EMA expression may represent the different origin of thymomas.