Although the PSA test itself is useful inmonitoring PCa progression, it lacks specificity in the detection of clinicallyimportant PCa in asymptomatic men.1 The identification of indolentcancers introduces the potential for harm, either from complications arising fromunnecessary investigations such as infection after biopsy,2 or from treatment complicationssuch as incontinence or impotence after surgery or radiotherapy(‘over-treatment’).3 False-negative PSA tests may offer false reassurance,leading to delayed presentation with more advanced disease and a poorerprognosis.1 This evidence concerns the gene KLK3 and posterior cortical atrophy.