KLK3 and Familial prostate cancer: However, the study by Marriel et al. indicates that PSA has a low specificity of 20%, disputing the usefulness of PSA in the accurate diagnosis of clinically significant prostate cancer (cs-PCa), since they recorded many cases with low PSA value and cs-PCa and, contrarily, high PSA value in benign pathologies like prostate hypertrophy [5].