脾边缘带淋巴瘤的临床及肿瘤细胞特征的研究

目的 提高对脾边缘带淋巴瘤（SMZL）的认识和诊疗水平,方法 报告1例典型SMZL,外周血,骨髓及脾脏标本分别采用光镜,相差显微镜,扫描电镜,免疫组化染色,流式细胞术,G显带核型分析及PCR技术研究其肿瘤细胞的生物学特征。结果 本例患者肿瘤细胞为B淋巴细胞,不伴有绒毛,表达CD20,HLA-DR、CD45RA和bcl-2,无异常核型,肿瘤细胞主要浸润脾脏白髓致边缘带明显扩大,脾门淋巴结受累,骨髓和外周血与脾脏有相同的单克隆IgH重排基因,治疗7个月后转为多克隆重排,结论 脾大,外周血或骨髓淋巴细胞比例增高而无淋巴结肿大和白细胞增高患者应疑及SMZL,单克隆IgH基因重排有助于SMZL的诊断,对可疑病例应尽早切脾以明确诊断及防止恶性转化。

The clinical features and tumor cells characteristics of splenic marginal zone lymphoma

OBJECTIVE: To deepen the understanding of splenic marginal zone lymphoma (SMZL) and improve the level of diagnosis and therapy. METHODS: A typical case of SMZL, a 61 year old female with lymphocytosis and splenomegaly found fortuitously, was reported. The pathologic, immunologic and genetic features of tumor cells in peripheral blood, bone marrow and spleen were studied with light microscopy, phase contrast microscopy, scanning electron microscopy, immunohistochemical method, flow cytometry, G chromosome banding technique and PCR for studying the pattern of IgH gene rearrangement. RESULTS: The spleen was large with uniform parenchyma and smooth surface. There were multiple small gray-white nodules on sections. Histologically, the neoplastic cells replaced the marginal and mantle zones with complete replacement of germinal centers in the white pulp. The neoplastic cells were predominantly of small to medium size with oval or slightly irregular nuclei. Lymph nodes in the splenic hilum were infiltrated by tumor cells. Immunophenotypic analysis demonstrated that the lymphocytes in the bone marrow expressed CD(20), HLA-DR, CD(45) RA and bcl-2. The monoclonal pattern of IgH gene rearrangement in peripheral blood and bone marrow was found to be the same as that in spleen. After splenectomy, COP chemotherapy and IFNalpha-2a were given and the abnormally increased lymphocytes decreased to normal level. Seven months later the monoclonal rearranged immunoglobulin heavy chain gene pattern changed to polyclonal pattern. CONCLUSION: Splenomegaly, lymphocytosis in peripheral blood and bone marrow without lymph node enlargement and leukocytosis are clinical characters of SMZL. Presence of monoclonal rearranged IgH gene is in favor of the diagnosis. Splenectomy should be done earlier in suspicious patients to avoid malignant transformation.