Objectives: To measure prostate volume doubling times (PVDTs) for a large sample of community men followed serially by transrectal ultrasonography (TRUS), and to determine whether specific characteristics are associated with a rapid PVDT.
Subjects and methods: A subsample of 446 subjects from a larger cohort of American white men aged 40-79 years were evaluated biennially for a median (range) follow-up of 10 (3-14) years. Mixed-effects regression models were used to estimate prostate growth rates and PVDT for subjects with three or more or with five or more serial biennial TRUS PV measurements.
Results: The median (25-75th percentile) PVDT was 32.6 (24.6-44.0) years. The average annual increase in PV was 2.2%. The PVDT distribution was constant in men of all age groups studied (r < 0.001, P = 0.99). The factor most strongly associated with PVDT was baseline transition zone volume (r = -0.55, P < 0.001). Baseline total prostate-specific antigen (PSA) level, free PSA and total PV were also significantly inversely associated with PVDT (r = -0.30, -0.44 and -0.32, respectively, all P < 0.001). Age, baseline anthropomorphic measurements, hormone levels and specific lifestyle characteristics were not significantly correlated with PVDT.
Conclusion: These data indicate that PVDT might be a useful future measure of benign prostatic growth. They provide a basis to forecast PV at 10, 20, or 30 years later, after one baseline TRUS measurement of prostate volume, and can be presented in a simple nomogram.