胸腔积液细胞病理学诊断浆母细胞淋巴瘤的探讨

目的探讨以细胞病理学及免疫细胞化学方法通过胸腔积液诊断浆母细胞淋巴瘤的特点。方法对1例浆母细胞淋巴瘤胸腔积液进行常规细胞学涂片、沉渣包埋、免疫组化染色、基因重排及EBV检测,并进行文献复习。结果胸腔积液涂片中细胞丰富,由单个散在或松散聚集的细胞组成,细胞大,有一定量的胞质,核浆比明显增高;部分胞质空泡状;核大,单核、双核或多核,圆或卵圆形,部分细胞核形不整,染色质细颗粒状,可见单个或多个核仁。大细胞间可见核偏位的浆细胞样细胞,核分裂易见,可见凋亡小体和易染体巨噬细胞。免疫组化:肿瘤细胞CD38和CD138(+),棕黄色颗粒沉积在细胞膜或部分胞质;MUM-1(+);B细胞标记物CD20、CD79α和PAX-5(-),T细胞标记物CD3、CD4和UCHL(-),CD15、CD30、ALK、calretinin、TTF-1、AE1/AE3和EMA(-)。Ki-67指数为90%。颈部淋巴结活检证实为浆母细胞淋巴瘤。免疫球蛋白Ig重链(IgH)单克隆性基因重排,EBV(-)。结论经胸腔积液诊断浆母细胞淋巴瘤少见,难度高。诊断及鉴别诊断对免疫组化的依赖程度较高。

Cytopathological diagnosis of plasmablastic lymphoma in pleural effusion

Objective To investigate the characteristics of cytopathological diagnosis and immunocytochemistry of plasmablastic lymphoma in the pleural effusion.Methods A case of plasmablastic lymphoma(PBL) in the pleural effusion was conventionally smeared,sedimentary embedded,and immunohistochemically stained,with PCR for T cell receptor and immunoglobulin gene rearrangement,in situ hybridization for Esptein-Barr virus-encoded small RNA(EBER),and review of the relevant literatures.Results H&E stained smears were hypercellular and composed of single cells with loosely formed clusters.The cells were large and had a certain amount of cytoplasm.The nuclear-to-cytoplamic ratio was consistently high,and nuclei were predominantly peripheral.The nuclei were large and oval to round in shape,with fine granular chromatin and multiple nucleoli or a single prominent central nucleolus.Some cells showed cytoplasmic vacuoles.Plasma cells and a few tangible body macrophages were identified.Mitotic figures were easily found.The tumor cells were diffusely and strongly expressed CD38 and CD138,but were negative for B cell markers(CD20,CD79α and PAX-5)and T cell markers(CD3,CD4 and UCHL-1),and aldo negative for CD15,CD30,ALK,calretinin,TTF-1,AE1/AE3 and EMA;the proliferation index of Ki-67 was 90%.Clonal IgH gene rearrangement was demonstrated.In situ hybridization for Esptein-Barr virus-encoded small RNA(EBER) was negative.The cervical lymph node biopsy confirmed the final diagnosis of plasmablastic lymphoma.The patient received two cycles of chemotherapy and left hospital.Conclusion It is difficult to diagnose plasmablastic lymphoma on cytological examination of pleural fluids.The immunocytochemical stains are helpful for its diagnosis and differential diagnosis.