Department of Surgical Pathology, Aichi Medical University Hospital, Nagakute, Japan.
Department of Gastroenterology and Hepatology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
J Clin Exp Hematop. 2022 Jun 28;62(2):106-113. doi: 10.3960/jslrt.21028. Epub 2022 Apr 27.
Immune evasion mediated by PD-L1 plays an important role in the development of B-cell malignancies. However, PD-L1 expression is infrequently observed in tumor cells of extranodal diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS). Other than copy number alterations, PD-L1 is aberrantly upregulated by structural variations in the 3'-UTR of PD-L1. We report four cases with PD-L1 expression on tumor cells, including two with structural variations in the 3'-UTR of PD-L1 and two without. Our report demonstrates the presence of a small number of "immune evasion-type" extranodal DLBCL, NOS cases.
PD-L1 介导的免疫逃逸在 B 细胞恶性肿瘤的发展中起着重要作用。然而，在结外弥漫性大 B 细胞淋巴瘤，非特指型（DLBCL，NOS）的肿瘤细胞中，PD-L1 的表达很少见。除了拷贝数改变外，PD-L1 的 3'-UTR 的结构变异也导致 PD-L1 异常上调。我们报告了 4 例肿瘤细胞表达 PD-L1 的病例，其中 2 例存在 PD-L1 的 3'-UTR 的结构变异，2 例不存在。我们的报告表明存在少数“免疫逃逸型”结外 DLBCL，NOS 病例。
