The Effect of Prostate Volume and 5-Alpha Reductase Inhibitor Use on Grade Progression and Treatment Decisions in Patients With Prostate Cancer on Active Surveillance.

PURPOSE: We evaluated the impact of prostate volume and 5-alpha reductase inhibitor (5-ARI) use on oncologic outcomes and benign prostatic hyperplasia management among patients undergoing active surveillance (AS) for low-grade prostate cancer (PCa).

MATERIALS AND

METHODS

We retrospectively reviewed patients with Grade Group (GG) 1 disease on AS. Multivariable extended Cox models examined the associations between prostate volume (at confirmatory biopsy), 5-ARI use, and 3 outcomes: grade progression (GP) on biopsy (to ≥GG 2 and extreme GP to ≥GG 3), receipt of a bladder outlet procedure, and definitive PCa treatment.

RESULTS

Among 1938 patients, 14% had prostate volumes < 30 cc, 73% had 30 to 80 cc, and 14% had > 80 cc. Patients with prostate volumes > 80 cc were more likely to undergo bladder outlet procedures (P < .001). On multivariable analysis, increasing prostate volume was associated with decreased rates of GP (HR 0.89, 95% CI 0.85-0.93, P < .001) and PCa treatment (HR 0.91, 95% CI 0.88-0.95, P < .001) per 10 cc; and 5-ARI use (per year) was associated with significant reductions in GP (HR 0.80, 95% CI 0.72-0.89, P < .001), extreme GP (HR 0.84, 95% CI 0.73-0.97, P = .02), and PCa treatment (HR 0.53, 95% CI 0.41-0.67, P < .001).

CONCLUSIONS

Among patients with low-grade PCa on AS, increased prostate volume was associated with lower risks of GP and receipt of definitive PCa treatment. Benign prostatic hyperplasia symptoms can safely be managed on AS, including with 5-ARIs, which were associated with lower risks of GP and progression to definitive treatment in this cohort.