CHEK2 and pachyonychia congenita: Germline pathogenic variants (PVs) in cancer predisposition genes are reported in 7.3% to 11.8% of aggressive prostate cancer (PC) cases, including genes associated with homologous repair deficiency (HRD) (e.g., BRCA1, BRCA2, ATM, BRIP1, CHEK2, NBN, BARD1, RAD51C, MRE11A, and PALB2), and mismatch repair (MMR) deficiency (e.g., MLH1, MSH2, MSH6, and PMS2).