To the Editor: In the Prostate Cancer Prevention Trial, an increased rate of high-grade cancer was observed in the finasteride group (1). The recently published analysis by Redman et al. (2) suggests that this observation was the result of detection bias rather than a true increase. However, the marked increase in the estimated rate of high-grade cancer in the placebo group calls into question the validity of the model. If the true rate of high-grade cancer in the placebo group was indeed 8.2%, then ∼40% of all high-grade cancers were missed despite annual screening. Because untreated, high-grade prostate cancer is associated with a 45% rate of metastatic disease after 5 years (3), one may conservatively estimate that 100 cases of metastatic prostate cancer should have developed in the placebo group in the 5 years since publication of the Prostate Cancer Prevention Trial. Do the authors have follow-up data to confirm this expectation?
Disclosure of Potential Conflicts of Interest
No potential conflicts of interest were disclosed.
- Received June 17, 2008.
- Accepted December 9, 2008.
- ©2009 American Association for Cancer Research.
Volume 2, Issue 2
