Treatment with finasteride preserves usefulness of prostate-specific antigen in the detection of prostate cancer: results of a randomized, double-blind, placebo-controlled clinical trial. PLESS Study Group. Proscar Long-term Efficacy and Safety Study.
OBJECTIVE
To evaluate prostate cancer detection and prostate-specific antigen (PSA) among men with benign prostatic hyperplasia treated with finasteride.


METHODS
Three thousand forty men 45 to 78 years of age with PSA less than 10 ng/mL and no history of prostate cancer were randomized in a double-blind, placebo-controlled trial to finasteride (n = 1524) or placebo (n = 1516) for up to 4 years. A prerandomization biopsy negative for prostate cancer was obtained in 98% of patients with a screening PSA of 4.0 ng/mL or more, and an end-of-study biopsy was requested of all such patients without a recent second negative biopsy or a prostate cancer diagnosis.


RESULTS
Overall, 644 patients (21%) underwent biopsy and 201 (6.6%) underwent transurethral resection of the prostate. Prostate cancer was diagnosed in 4.7% of men on finasteride and 5.1% on placebo (P = 0.7). Elevated PSA prompted diagnosis in 35% of cases on finasteride and 34% on placebo. The area under the receiver operating characteristic curve for last PSA was 0.84 on finasteride and 0.79 on placebo (P = 0.07). Use of an upper limit of normal for last PSA of 2.0 ng/mL for finasteride and 4.0 ng/mL for placebo yielded similar sensitivity (66% versus 70%, P = 0.6), higher specificity (82% versus 74%, P < 0.0001), and a higher likelihood ratio (3.6 versus 2.7, P < 0.05) for finasteride than for placebo.


CONCLUSIONS
In men treated with finasteride, multiplying PSA by 2 and using normal ranges for untreated men preserves the usefulness of PSA for prostate cancer detection.
Andriole
G L
GL
Division of Urology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Guess
H A
HA
Epstein
J I
JI
Wise
H
H
Kadmon
D
D
Crawford
E D
ED
Hudson
P
P
Jackson
C L
CL
Romas
N A
NA
Patterson
L
L
Cook
T J
TJ
Waldstreicher
J
J
D000368:Aged; D004311:Double-Blind Method; D018120:Finasteride / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D017430:Prostate-Specific Antigen / Q000097:blood*; D011470:Prostatic Hyperplasia / Q000188:drug therapy*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000175:diagnosis*; D012680:Sensitivity and Specificity
D018120:Finasteride; D017430:Prostate-Specific Antigen