Due to the increased sensitivity and specificity of modern imaging modalities, the oligometastatic prostate cancer (PC) is diagnosed more often, thus many patients considered non-metastatic on conventional imaging (computed-tomography (CT) and bone scintigraphy) turn out to be oligometastatic even at a low prostate-specific antigen (PSA) serum level. This evidence concerns the gene KLK3 and pachyonychia congenita.