KLK3 and benign prostatic hyperplasia: Another paradigmatic example of the importance of PSA glycoforms in support of future clinical decisions is the study of Ferrer-Betallè et al. They compared the performance of PHI with a glycoform assay measuring the α2,3-sialic acid percentage of PSA in serum to discriminate between BPH and PCa patients (BPH = 29 and low-risk = 7, intermediate risk = 21, high-risk = 22 PCa) [69].