A study aimed to assess pre- and early postoperative levels of important prostate specific antigen (PSA) isoforms and human kallikrein-2 (hK2) to discern their ability to predict biochemical recurrence (BCR) and identify disease persistence (DP) after radical prostatectomy (RP) for prostate cancer. The study was published in Tumour Biology.
“The role of isoforms of PSA and other kallikrein-related markers in early detection of BCR after RP is not well known and serum PSA is currently used in preoperative risk nomograms,” the researchers wrote.
This study consisted of 128 consecutive patients who underwent RP for clinically localized prostate cancer. The researchers preoperatively measured PSA, free PSA (fPSA), the free/total PSA ratio (%fPSA), [-2]proPSA (an fPSA isoform), Prostate Health Index (PHI) and hK2 at one- and three-months following RP.
The results showed that preoperatively, the independent predictors of BCR were PSA (P=0.029), [-2]proPSA (P=0.002) and PHI (P=0.0003). Post-RP, the researchers noted, PSA was the single marker correlating with BCR, both at one (P=0.0047) and three months (P=0.0004). They further noted that PSA, fPSA, [-2]proPSA and PHI were notably linked to DP at 1- and 3-months post-RP (P<0.05), although PSA had the most significant existing correlation (P<0.0001).
The researchers concluded that: “[-2]proPSA and PHI are preoperative predictors of BCR and DP that outperform the currently used serum PSA. At the early postoperative period there is no additional benefit of the other markers tested.”