Three-year postoperative ultrasensitive prostate-specific antigen following open radical retropubic prostatectomy is a predictor for delayed biochemical recurrence.

Abstract

Prostate-specific antigen (PSA) is the only independent predictor of biochemical recurrence (BCR) following radical prostatectomy (RP) subject to change over time. To determine whether an ultrasensitive PSA measured at 3 yr following RP is a predictor of subsequent BCR. There were 1197 consecutive men with clinically localized prostate cancer who underwent an open radical retropubic prostatectomy (ORRP) at a tertiary referral academic medical center. Exclusions included 107 men (8.9%) who developed a PSA level ≥ 0.2 ng/ml or underwent hormone therapy or radiation therapy (RT) within the first 3 r after surgery, 191 men (16%) who did not undergo a 3-yr ultrasensitive PSA assay, and 98 men (8.2%) who had PSA levels ≥ 0.1 and <0.2 at 3 yr. The remaining 801 men were stratified into two groups based on their ultrasensitive PSA level at 3 yr postoperatively: group 1, which consisted of patients whose PSA was ≤ 0.04 (n = 765), and group 2, which consisted of patients whose PSA was >0.04 and <0.10 (n = 36). Delayed BCR was the primary end point and represented those men in this cohort who developed a PSA level ≥ 0.2 or underwent salvage RT for a persistently rising PSA level after 3 yr of follow-up. The 7-yr cumulative BCR-free survival rate for groups 1 and 2 was 0.957 (95% confidence interval [CI], 0.920-0.978) and 0.654 (95% CI, 0.318-0.855), respectively. In multivariable Cox proportional hazards models, ultrasensitive PSA level at 3 yr remained the only significant predictor of delayed BCR (likelihood ratio χ(2) for full model: 27.03; df = 1; p < 0.001). A limitation of the study is that no uniform PSA assay was obtained. Our findings provide compelling evidence that an ultrasensitive PSA at 3 yr following RP provides useful insights into delayed BCR and is a source of reassurance for the overwhelming majority of men being followed for delayed recurrences.