Some authors found that 1–2% of young-onset PC patients had a germline BRCA2 mutation, conferring a five to seven-fold greater lifetime risk for developing PC (three to eight-fold greater risk for BRCA1 mutations) [10,192]; other studies estimated a 20% lifetime risk for BRCA2-mutated patients (9.5% for BRCA1-mutated carriers) [169,186]. Here, BRCA2 is linked to pachyonychia congenita.