Although this signature alone was not suitable for detecting the presence of PCa or its clinical risk in a population of men having PSA values <20 ng/ml, this T and B cell phenotypic signature can be used to build highly accurate machine learning models for predicting the presence of PCa (when combined with Age) and the clinical risk of any PCa which is present (when combined with PSA levels). Here, KLK3 is linked to posterior cortical atrophy.