Study of clinicopathologic features of primary mediastinal B-cell lymphoma

目的 研究中国人原发纵隔大B细胞淋巴瘤(PMBL)的临床及病理学特征；探讨其与弥漫大B细胞淋巴瘤非特指型(DLBCL,NOS)在临床病理学特点及预后方面的差异.方法 收集24例PMBL作为研究对象,以31例DLBCL,NOS作为对照组,进行免疫组织化学标记并进行临床随访.结果 PMBL组发病中位年龄30岁,对照组中位年龄61岁,两组年龄分布差异有统计学意义(P＜0.001).临床上PMBL组纵隔压迫症状常见.组织形态上,PMBL组肿瘤细胞符合DLBCL的形态学特点.全部病例均可见程度不等的间质硬化,超过70.8％(17/24)的病例可见明显的胶原束分割.免疫表型上PMBL组40.0％(6/15)表达CD23,与对照组(3.2％,1/31)差异有统计学意义(P=0.003).结论 PMBL具有独特的临床病理学特点,常见于年轻女性,以纵隔巨大占位及纵隔相关区域侵犯多见,全身系统性累及少见.PMBL形态学特点为弥漫性增生的肿瘤细胞被粗细不等的胶原纤维分割.CD23阳性有助于与DLBCL,NOS的鉴别诊断.Objective To elucidate clinical pathological features of primary mediastinal B-cell lymphoma (PMBL) and its difference compared with diffuse large B-cell lymphoma,not otherwise specified (DLBCL,NOS).Methods The clinical histories and pathological datas of 24 PMBL cases and 31 cases of DLBCL,NOS as the control group were collected.Immunohistochemical staining and a follow-up study was conducted.Results The distribution of gender showed significant difference when the age of onset of PMBL patients was obviously younger with the medial age of 30 years old (P ＜ 0.001).All cases presented as a huge mass in mediastinal site with compression symptoms.PMBL was similar to DLBCL in the morphology of tumor cells but fibrosis of various degrees was common,more than 70.8 ％ (17/24) cases had the collagen bundles split.CD23 positive rate (40.0 ％,6/15) in PMBL was significantly higher than the control group (3.2 ％,1/31)(P =0.003).Conclusion PMBL frequently occurs in young female people,mostly happens in mediastinal site and adjacent area,but rarely has distant dissemination.PMBL has the characteristics of various degrees of collagen fiber hyperplasia,and CD23 positive could be used to differentiate PMBL from DLBCL,NOS.012720-7222