The programmed death 1 (PD1)/PD1 ligand (PD-L1) axis plays an important role in the pathogenesis of Epstein-Barr virus-positive diffuse large B cell lymphoma, not otherwise specified (EBV+ DLBCL, NOS). Here, we describe PD-L1 expression by EBV+ DLBCL, NOS in order to evaluate its possible contribution to the pathogenesis of this tumor. The study included 57 cases of EBV+ DLBCL, NOS. The median patient age was 69 years and 95% (n = 54) were aged > 45. Extranodal lesions were present in 39 (69%) at initial diagnosis. PD-L1 expression (mAb SP142-positive staining) was present in more than 5% of tumor cells in only six cases (11%), in clear contrast to the 77% reported in cases aged under 45 years. Among the PD-L1+ cases, three were nodal lesions. All six PD-L1+ cases progressed in the 3 years after diagnosis and four of the six patients died of the disease within 2 years. PD-L1+ cases had significantly shorter PFS (P = 0.002) and relatively short OS (P = 0.26), compared with PD-L1− cases. EBV+ DLBCL, NOS in the elderly infrequently expressed PD-L1 and had poor prognosis. PD-L1 expression in EBV+ DLBCL, NOS of the elderly sheds light on the pathogenetic role of immune senescence.

程序性死亡1（PD1）/ PD1配体（PD-L1）轴在爱泼斯坦-巴尔病毒阳性的弥漫性大B细胞淋巴瘤的发病机理中起着重要作用，除非另有说明（EBV + DLBCL，NOS）。在这里，我们描述了EBV + DLBCL，NOS的PD-L1表达，以评估其对该肿瘤发病机理的可能贡献。该研究包括57例EBV + DLBCL，NOS。患者中位年龄为69岁，95％（n = 54岁）的年龄大于45岁。初诊时有39例（69％）存在结外病变。PD-L1表达（mAb SP142阳性染色）仅在6例（11％）的病例中出现在5％以上的肿瘤细胞中，这与45岁以下病例中报告的77％形成鲜明对比。在PD-L1 +病例中，三例为淋巴结病变。所有6例PD-L1 +病例均在诊断后3年内进展，而6例患者中有4例在2年内死亡。 与PD-L1-病例相比，PD-L1 +病例的PFS明显短（P  = 0.002），而OS相对较短（P = 0.26）。老年人EBV + DLBCL，NOS很少表达PD-L1，预后较差。老年人EBV + DLBCL，NOS中PD-L1的表达阐明了免疫衰老的致病作用。