Reply Free

In Response: We appreciate the opportunity to respond to Dr. Edwards. We did not witness a high rate of death from prostate cancer over the course of the trial (an event expected about 30-36 months after the development of metastases) nor would we expect this to be common during intermediate follow-up. The citation (reference 3) is a compilation of a group of studies published in the 1980s and 1990s summarizing the outcomes of patients diagnosed over several decades before the time of the report. These patients were largely diagnosed with symptoms and, unusually, with regular rectal examination screening. We previously observed that even with regular rectal examination screening, two thirds of patients had prostate cancer that had spread beyond the confines of the prostate (1). In the majority of patients with symptoms from their prostate cancer, the disease is generally metastatic. As such, the reference used by Dr. Edwards is inappropriate as a comparator for high-grade cancers diagnosed in the Prostate Cancer Prevention Trial because they were diagnosed in the context of frequent prostate-specific antigen measurement and were generally of far lower volume and stage than those reported in previous series.

A long-term follow-up study of patients diagnosed with prostate cancer in the Prostate Cancer Prevention Trial is ongoing, but due to the very early detection of these patients, it is not expected that metastases will be frequent event, simply due to very early cancer detection.