Freedom from a detectable ultrasensitive prostate-specific antigen at two years after radical prostatectomy predicts a favorable clinical outcome: analysis of the SEARCH database.
OBJECTIVE
To assess the utility of kinetics for ultrasensitive prostate-specific antigen (uPSA) assays to identify men who are at risk of developing high-risk recurrent prostate cancer [prostate-specific antigen doubling time (PSADT) < 9 months] after radical prostatectomy. Previous studies demonstrate that a PSADT < 9 months after radical prostatectomy is associated with prostate cancer-specific mortality. Conventionally, PSADT has been calculated after biochemical failure (PSA > or = 2 0.2 ng/mL).


METHODS
A review of the Shared Equal Access Regional Cancer Hospital database from 1988-2008 was performed to identify men with biochemical failure after radical prostatectomy and > or = 2 uPSA values before failure (PSA > or = 2 0.2 ng/mL) as well as > or = 2 2 values after failure to calculate PSADT. These patients were stratified into low-risk (PSADT > or = 2 9 months) and high-risk (PSADT < 9 months) cohorts. The following uPSA kinetics were analyzed for their ability to predict low- and high-risk cohorts: time to first detectable uPSA, time from uPSA to biochemical failure, uPSA velocity, uPSADT, uPSA exponential rise, and uPSA fluctuations.


RESULTS
The analysis included 89 low- and 26 high-risk men. Time to first detectable uPSA was inversely associated with the high-risk cohort (OR 0.96, 95% CI 0.92-0.99, P = .02) and characterized by a high sensitivity and negative predictive value at a threshold of 2 years after surgery. Other measures of uPSA kinetics showed no association with PSADT.


CONCLUSIONS
Time to first detectable uPSA identifies men with low-risk recurrence prostate cancer. Patients with an undetectable uPSA 2 years after surgery are unlikely to develop PSADT < 9 months after biochemical failure.
Chang
Steven L
SL
Department of Urology, Stanford University Medical Center, Stanford, California 94305, USA. slchang1@stanford.edu
Freedland
Stephen J
SJ
Terris
Martha K
MK
Aronson
William J
WJ
Kane
Christopher J
CJ
Amling
Christopher L
CL
Presti
Joseph C
JC
D016208:Databases, Factual; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood* / Q000453:epidemiology; D011237:Predictive Value of Tests; D017430:Prostate-Specific Antigen / Q000097:blood*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000097:blood* / Q000453:epidemiology / Q000601:surgery*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
D017430:Prostate-Specific Antigen