摘要目的:探讨伴IRF4重排的大B细胞淋巴瘤的临床病理学特征。方法:收集南京医科大学第一附属医院病理科2018年11月至2019年9月间诊断的7例伴IRF4重排的大B细胞淋巴瘤，行HE和免疫组织化学染色及荧光原位杂交检测，并复习相关文献。结果:（1）7例患者中男性3例，女性4例，年龄6~39岁，中位年龄24岁，其中发病部位4例扁桃体、2例淋巴结和1例腺样体。（2）形态上，1例完全滤泡样构型，2例完全弥漫构型，余4例两者兼有。瘤细胞多为中等至大的体积，中心母细胞样形态或不规则核的母细胞样细胞；3例核分裂象活跃（12~20个/HPF），2例伴星空现象。（3）免疫表型上，瘤细胞均表达CD20、PAX5、bcl-6和MUM1；其中3例CD10和bcl-2阳性；Ki-67阳性指数均>80%。7例IRF4基因断裂重排，其中2例bcl-6基因重排。（4）6例患者临床均为Ⅰ~Ⅱ期，1例为临床Ⅳ期，后者随访8个月后PET/CT提示纵隔新发病灶。结论:伴IRF4重排的大B细胞淋巴瘤是一种具有独特临床病理表现的大B细胞淋巴瘤，结果提示其可能具有更广的形态学和生物学行为谱系。肿瘤临床分期与预后的关系尚需要更多的临床病例观察进一步明确。

abstractsObjective:To study the clinicopathological features of large B-cell lymphoma (LBCL) with IRF4 rearrangement.Methods:Seven cases of LBCL with IRF4 rearrangement collected at the First Affiliated Hospital of Nanjing Medical University from November 2018 to October 2019 were evaluated by hematoxylin and eosin staining, immunohistochemistry and fluorescence in situ hybridization detection. The relevant literature was reviewed.Results:Four tumors were located in the tonsils, 2 tumors in the lymphoid nodes and one tumor in the adenoid.The patients were 3 males and 4 females patients with a median age of 24 years (range, 6 to 39 years).Microscopically, entirely follicular pattern was present in one case, entirely diffuse pattern in 2 cases, and follicular and diffuse pattern in other 4 cases. The tumor cells were medium to large in size and showed the morphology of centroblasts or blastoid cells with irregular nuclei, brisk mitotic activity in 3 cases and starry sky in 2 cases. All of the cases were positive for CD20, PAX-5, bcl-6, and MUM1 and had a Ki-67 index>80%, while CD10 and bcl-2 were positive in 3 cases. IRF4 gene rearrangement was identified in all cases and bcl-6 gene rearrangement in 2 cases. All patients presented with localized disease with clinical stage Ⅰ or Ⅱ, except one with stage Ⅳ at presentation and a new lesion in the mediastinum developed 8 months later.Conclusions:LBCL with IRF4 rearrangement is a clinicopathologically distinct entity. The observations reveal a broader spectrum of morphology and biological behaviors. The relationship between clinical stage and prognosis needs to be determined in more cases.