Decreased suburethral prostatic microvessel density in finasteride treated prostates: A possible mechanism for reduced bleeding in benign prostatic hyperplasia

Purpose: We evaluated the influence of finasteride on prostatic microvessel density to elucidate a mechanism of decreased bleeding in finasteride treated patients with hematuria secondary to benign prostatic hyperplasia (BPH). Materials and Methods: A total of 22 patients with clinical BPH and gross hematuria who underwent prostate reductive surgery between 1998 and 2000 were prospectively evaluated. The prostate from 10 finasteride treated and 12 untreated patients was immunohistochemically stained for CD-34. Microvessel density analysis was performed by quantifying positive stained blood vessels located within the stroma of hyperplastic nodules as well as in the suburethral portion of the prostate. Results: Mean microvessel density plus or minus standard deviation in finasteride treated patients was significantly lower in the suburethral portion of the prostate versus untreated controls (14.0 +/- 2.8 versus 20.2 +/- 5.3 vessels per high power field, p <0.05). In the nodular hyperplasia there was no statistically significant difference in the treatment and control groups (mean 17.5 +/- 2.8 and 16.7 +/- 4.6 vessels per high power field, respectively). Conclusions: Finasteride significantly decreases suburethral prostatic microvessel density in patients with BPH, which may explain its efficacy for decreasing BPH associated bleeding.