Ondrejka Sarah L, Ott German
Department of Laboratory Medicine, Cleveland Clinic, Cleveland, OH, USA.
Department of Clinical Pathology, Robert-Bosch-Krankenhaus, Stuttgart, Germany.
Am J Clin Pathol. 2021 Sep 8;156(4):497-512. doi: 10.1093/ajcp/aqab122.
Primary mediastinal (thymic) large B-cell lymphoma (PMBL) is an uncommon large B-cell neoplasm recognized by the World Health Organization as a distinct entity on the basis of its unique clinical features, histogenesis, phenotype, and pathogenetic mechanisms. The diagnosis of PMBL can be challenging because of features that may overlap with other (Hodgkin and non-Hodgkin) lymphoma types. This review describes our approach to the diagnosis of PMBL.
Two cases are presented to illustrate how we diagnose PMBL and separate PMBL from related histologic and biological mimickers, such as Hodgkin lymphoma and gray zone lymphoma.
A diagnosis of PMBL requires correlation of morphology and immunophenotype with clinical and staging data. Gene expression analysis is not typically performed in clinical labs but has expanded our understanding of the functional pathways underlying this disease and helped identify biomarkers that can be translated to diagnostic practice and possibly to future therapeutic options.
PMBL and closely related entities can pose diagnostic challenges. It is important to understand the borders between PMBL and other closely related lymphoma types so that patients receive successful primary treatment with curative intent.
原发性纵隔（胸腺）大B细胞淋巴瘤（PMBL）是一种罕见的大B细胞肿瘤，世界卫生组织基于其独特的临床特征、组织发生、表型和致病机制将其认定为一种独特的实体。由于其特征可能与其他（霍奇金淋巴瘤和非霍奇金淋巴瘤）淋巴瘤类型重叠，PMBL的诊断可能具有挑战性。本综述描述了我们诊断PMBL的方法。
介绍两例病例，以说明我们如何诊断PMBL，并将PMBL与相关的组织学和生物学模仿者（如霍奇金淋巴瘤和灰色地带淋巴瘤）区分开来。
PMBL的诊断需要将形态学和免疫表型与临床和分期数据相关联。基因表达分析通常不在临床实验室进行，但它扩展了我们对该疾病潜在功能途径的理解，并有助于识别可转化为诊断实践以及可能用于未来治疗选择的生物标志物。
PMBL及密切相关实体可能带来诊断挑战。了解PMBL与其他密切相关淋巴瘤类型之间的界限很重要，以便患者接受旨在治愈的成功初始治疗。
