FH of PC and/or related cancers is defined as having any of:- PC (except localized Grade Group 1) in brother, father or multiple family members diagnosed at age < 60 years;- Death from PC in a first-degree relative aged < 60 years;- Known germline mutations of BRCA1/2 or DNA MMR genes in the family;- BRCA1/2m-associated cancer or Lynch syndrome (namely: bile duct, breast, colorectal, endometrial, gastric, kidney, melanoma, ovarian, pancreatic, prostate [except localized Grade Group 1], small bowel or urothelial cancer) in ≥ 3 members on the same side of the family. The gene discussed is BRCA1; the disease is pachyonychia congenita.