Purpose: In the present analysis we examined data from the MTOPS (Medical Therapy of Prostatic Symptoms) trial to determine the effect of long-term finasteride treatment, either alone or in combination with doxazosin, on total prostate volume across the full range of baseline total prostate volume values in men enrolled in this study.
Materials and methods: In this trial a total of 3,047 patients with lower urinary tract symptoms were randomized to placebo, doxazosin (4 to 8 mg), finasteride (5 mg) or the combination of doxazosin and finasteride (average length of treatment 4.5 years). Total prostate volume was measured by transrectal ultrasound in all patients at baseline, yearly and at study end or at termination of participation.
Results: Long-term treatment with finasteride led to a consistent reduction of approximately 25% in total prostate volume compared to placebo in men with a relatively small prostate (less than 25 to 30 ml), as well as in those with a moderate size (30 to less than 40 ml) or enlarged prostate (40 ml or greater) at baseline.
Conclusions: In this MTOPS data analysis long-term (more than 4 years) treatment with finasteride, either alone or in combination with doxazosin, led to a consistent, clinically significant reduction in total prostate volume compared to placebo in patients with lower urinary tract symptoms and benign prostatic hyperplasia whose baseline prostate size ranged from relatively small (less than 25 to 30 ml) to enlarged (40 ml or greater).