Low Frequency of Programmed Death Ligand 1 Expression in Pediatric Cancers. Issue 8 (2nd May 2016) - Aoki, Takahiro
Abstract : Programmed death 1 (PD‐1)/programmed death ligand 1 (PD‐L1) pathway blockade has become a promising therapeutic target in adult cancers. We evaluated PD‐L1 expression and tumor‐infiltrating CD8 + T cells in formalin‐fixed, paraffin‐embedded tumor specimens from 53 untreated pediatric patients with eight cancer types: neuroblastoma, extracranial malignant germ cell tumor, hepatoblastoma, germinoma, medulloblastoma, renal tumor, rhabdomyosarcoma, and atypical teratoid/rhabdoid tumor. One rhabdomyosarcoma with the shortest survival exhibited membranous PD‐L1 expression and germinoma contained abundant tumor‐infiltrating CD8 + T cells and PD‐L1‐positive macrophages. The PD‐1/PD‐L1 pathway tended to be inactive in pediatric cancers.