Prostate tissue composition and response to finasteride in men with symptomatic benign prostatic hyperplasia.
OBJECTIVE
We sought to quantify prostate tissue changes induced by finasteride and to identify a predictor of finasteride response in men with symptomatic benign prostatic hyperplasia (BPH) via a randomized, placebo controlled, double-blind clinical trial.


METHODS
Men with symptomatic BPH (52 to 78 years old) were randomly assigned to 6 months of treatment with finasteride (26) or placebo (15). Outcome measures were clinical (urinary symptom score and flow rate), chemical (serum prostate specific antigen and dihydrotestosterone levels), volumetric (transrectal ultrasound, and magnetic resonance imaging for whole and zonal prostate volumes) and histological (morphometry of prostate sextant biopsies, separated into inner and outer gland segments, to measure the percent epithelium, stroma and glandular lumen).


RESULTS
In the finasteride group we found a suggestion of decreasing symptom scores and increasing flow rates (not significant) with significant decreases (p < 0.01) in prostate specific antigen (48%), dihydrotestosterone (74%) and prostate volume (21%). Finasteride treatment induced a 55% decrease in inner gland epithelium (p < 0.01) with little effect on stroma or lumina. We also found a linear correlation between pretreatment inner gland epithelial content and prostate volume decrease induced by the drug (tau = 0.58, p = 0.01).


CONCLUSIONS
Finasteride treatment results in a major suppression of prostate epithelium, which is most pronounced in the inner gland. Moreover, a finasteride induced prostate volume decrease was predictable by quantification of epithelial tissues of the inner gland. These data lend additional support to the emerging concept of transition zone primacy in symptomatic BPH.
Marks
L S
LS
Department of Surgery/Urology, UCLA School of Medicine, USA.
Partin
A W
AW
Gormley
G J
GJ
Dorey
F J
FJ
Shery
E D
ED
Garris
J B
JB
Subong
E N
EN
Stoner
E
E
deKernion
J B
JB
D000368:Aged; D013196:Dihydrotestosterone / Q000097:blood; D004311:Double-Blind Method; D004791:Enzyme Inhibitors / Q000627:therapeutic use*; 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 / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology*; D012074:Remission Induction; D014463:Ultrasonography
D004791:Enzyme Inhibitors; D013196:Dihydrotestosterone; D018120:Finasteride; D017430:Prostate-Specific Antigen