Objective: Investigate whether prostate volume is a moderating variable for the incidence of prostate cancer (PCa). Methods: Study participants in the control arm whose cancer status was verified per biopsies during the 7-year study period were included for analysis. Simple and multivariable logistic regression analyses including parameters such as age and race were applied. Results: PCa was diagnosed in 1132 (24.3%) of Prostate Cancer Prevention Trials (PCPT) participants. Simple logistic regression demonstrated a statistically significant reduction in PCa incidence for patients with prostate volumes larger than 60 cc. Risk of aggressive cancer (Gleason grade ⩾ 7) was also significantly lower in men with prostate volumes greater than 60 cc (aOR = 0.585, p = 0.000) when controlling for age, family history of cancer, and race. Conclusions: Stratifying the PCPT data by prostate size with considerable statistical power revealed a highly significant ( p = 0.000) difference between the incidence of PCa in large (⩾60 cc) and moderate to small (<60 cc) prostates, not only for general PCa but also for high-grade cancer. These results support the clinical hypothesis that prostate/benign prostate hyperplasia size may have a protective effect on the incidence of PCa. Level of evidence: Not applicable.
Seyan et al. (Fri,) studied this question.