一种新的淋巴瘤亚型：bcl-2和myc易位的双击淋巴瘤

A new subtype of iymphoma：double-hit lymphoma with bcl-2 and myc translocation

双击淋巴瘤（DHL）特征介于弥漫大B细胞淋巴瘤（DLBCL）和伯基特淋巴瘤（BL）之间，通常伴有myc基因断裂和其他重现性染色体断裂的疾病，常见myc和bcl-2基因的易位。其临床表现具有乳酸脱氢酶升高、骨髓受累、AnnAbort分期晚期、B症状、结外受累、侵犯中枢神经系统等特征。因与DLBCL和BL有部分重叠，所以依靠病理诊断很难将其区分出来，目前主要的诊断方法为G显带染色体核型分析、荧光原位杂交（FISH）检测以及免疫组织化学技术。DHL对于DLBCL的标准化疗方案反应较差，预后不佳，中位生存期仅为0．2～1．5年。目前DHL尚无较好的治疗方法，主要方案为RCHOP、RICE、RCVD、甲氨蝶呤预防中枢神经系统受累、大剂量化疗联合骨髓移植等。

Double-hit lymphoma （DHL） is a kind of disease with features intermediated between diffuse large B-cell lymphoma （DLBCL） and Burkitt lymphoma （BL）, usually accompanied by myc gene breakpoint with other recurrent chromosomal breakpoint and mainly involving myc and bcl-2 translocation. The presentation of this disease is characterized by elevated serum lactate dehydrogenase levels, B symptoms, bone marrow involvement, advanced stage disease, extranodal involvement, and central nervous system involvement. Because its features are similar with DLBCL and BL, it ~s difficult to distinguish them by pathological diagnosis. At present, the differential diagnosis is mainly by chromosomal analysis （G-banding）, FISH and immunohistochemistry. This subtype received a poor response to conventional chemotherapy for DLBCL, and has a poor prognosis. The median survival time is only 0.2-1.5 years. Currently, the main regimens include RCHOP, RICE, RCVD, methotrexate prophylaxis for central nervous system involvement, high-dose chemotherapy and bone marrow transplantation.