Following European Association of Urology (EAU), high-risk PC is defined as Gleason score ≥ 8 (International Society of Urological Pathology grade group; ISUP GG ≥ 4), prostate-specific antigen (PSA) >20 ng/ml, or clinical stage ≥T2c, but this definition varies between different guidelines. The gene discussed is KLK3; the disease is pachyonychia congenita.