原发中枢神经系统淋巴瘤的脑脊液细胞学诊断

Role of Cerebrospinal Fluid Cytology in Diagnosis of Primary Central Nervous System Lymphoma

目的研究脑脊液细胞学方法对原发中枢神经系统淋巴瘤(primary central nervous system lymphoma,PC-NSL)的诊断意义。方法回顾性分析21例脑脊液细胞学阳性的PCNSL患者的临床资料,PCNSL的诊断综合应用脑脊液细胞学、脑脊液免疫细胞化学、脑脊液淋巴细胞基因分析和流式细胞分析等方法。结果 21例患者临床-神经影像学分型包括脑脊膜型13例,实质型4例,室管膜(下)型3例,眼型1例。脑脊液细胞学检查21例均见淋巴瘤细胞或异型淋巴细胞。脑脊液免疫细胞化学检查17例呈B淋巴细胞优势,符合B淋巴细胞来源淋巴瘤,10例Ki67阳性细胞比例在40%～60%。7例流式细胞分析中5例以B细胞为主,B细胞比例66%～87%;1例以NK/T细胞为主。脑脊液淋巴细胞基因重排检测3例为IgH单克隆,1例为T细胞受体单克隆。最终6例行脑活检并确诊PCNSL。综合上述结果,21例确诊PCNSL,其中B细胞型19例,T细胞型2例。结论综合应用脑脊液细胞学、免疫细胞化学、细胞基因重排检测和流式细胞分析的脑脊液学方法,是诊断PCNSL的重要途径。

Objective To study the diagnostic value of cerebrospinal fluid （CSF） cytology in the diag- nosis of primary central nervous system lymphoma （PCNSL）. Methods We retrospectively analyzed the clini- cal data of 21 PCNSL patients with positive CSF cytological findings. Conventional CSF cytology, immunocyto- chemistry, flow cytometric immunophenotypic analysis （FCA） , and PCR of the rearranged IgH and TCR genes of CSF were performed. Results The clinical and neuroimaging types of 21 patients included meningeal type （ n = 13 ）, parenchymal type （ n = 4）, ependymal type （ n = 3 ）, and optic type （ n = 1 ）. The CSF of all the 21 patients had a number of blast cells or atypical lymphocytes, suspected of lymphoma on conventional cytology.Of the 20 patients undergoing the immunocytochemical studies of the CSF, 17 showed B-lymphocyte predomi- nance, which was consistent with the diagnosis of B cell lymphoma. FCA of 7 cases showed a significant increase in the percentage of B cells in 5 patients, indicating B cell lymphoma, and NK/T-lymphocyte predominance in 1 case, indicating an NK/T lymphoma. On analysis of the IgH and TCR genes in the CSF of 4 patients, IgH mono- clonal was found in 3 cases and TCR monoclonal in 1 case. Conclusion CSF cytology, immunocytochemistry, FCA, and PCR of the rearranged IgH and TCR genes of CSF are useful in tile diagnosis of PCNSL.