Primary NMZL cases harboring PTPRD lesions show a cell-cycle signature and an increased proliferation index. (A) GSEA plot illustrating the enrichment and upregulation of different biologically relevant gene sets (E2F pathway and G2M cell-cycle checkpoints) in PTPRD mutated/deleted vs PTPRD wild-type. Genes with an enrichment score <0.1 are shown. GSEA, Gene Set Enrichment Analysis; FDR, false discovery rate. (B) Ki-67 expression by immunohistochemical analysis of the lymph node biopsy from one exemplificative PTPRD-mutated NMZL case and one exemplificative PTPRD wild-type case (original magnification ×10). (C) Comparison of the Ki-67 proliferation index assessed by immunohistochemistry between PTPRD-mutated/deleted cases vs PTPRD wild-type NMZL (median, black line inside the bar; quartiles, margin of the box; range, whiskers). P value by Mann-Whitney U test.