_SelectMDx® (MDxHealth, Irvine, CA, USA): an algorithm based on urinary mRNA levels of HOXC6, distal-less homeobox 1 (DLX1), and KLK3 (encoding for PSA) genes, combined with age, PSA-density, DRE, and family history of PC. Here, KLK3 is linked to pachyonychia congenita.