单形性亲上皮性肠道T细胞淋巴瘤的病理学特征及MATK表达的诊断价值

Pathological features and diagnostic value of the expression of MATK in monomorphic epitheliotropic intestinal T-cell lymphoma

目的:探讨单形性亲上皮性肠道T细胞淋巴瘤(MEITL)的临床病理特征及巨核细胞相关酪氨酸激酶(MATK)表达的意义。方法:分析19例MEITL患者MEITL的病理组织形态学和免疫表型特点。结果:MEITL患者的肿瘤细胞小至中等大小,瘤细胞规则,核圆形,核仁不明显,胞质淡染。肿瘤细胞具有显著的亲上皮现象,缺乏炎症和坏死背景。肿瘤细胞表达CD3、CD8、CD56和TIA1,不表达CD5,EBER原位杂交均阴性。MATK高表达,阳性率超过80%。结论:MEITL是罕见的侵袭性原发性肠道T细胞淋巴瘤,诊断和鉴别诊断依赖于组织形态学和独特的免疫表型。MATK高表达有助于MEITL与其他肠道T细胞淋巴瘤的鉴别诊断。

Objective:To elucidate the clinicopathologic features and the expression of megakaryocyte-associated tyrosine kinase(MATK)in monomorphic epitheliotropic intestinal T-cell lymphoma(MEITL).Methods:The histomorphological features and immunophenotype of 19 patients with MEITL were analyzed.Results:The neoplastic cells were generally small to medium in size with regular appearance.The nuclei were round with inconspicuous nucleoli.There was a generous rim of pale cytoplasm.The tumour cells showed prominent epitheliotropism while rarely demonstrated inflammatory or necrosis background.All cases presented distinctive immunophenotype,including positive expression for CD3,CD8,CD56,TIA1 and negative for CD5.In situ hybridization for Epstein-Barr virus encoded small nuclear RNAs(EBER)of the 19 patients were negative.Furthermore,MATK were highly expressed in more than 80%of the tumour cells.Conclusion:MEITL is a rare,aggressive primary intestinal T-cell lymphoma.The diagnosis and differential diagnosis of MEITL are mainly based on the histomorphological features and distinct immunophenotypes.The high expression of MATK may distinguish MEITL from other intestinal T-cell lymphomas.