The Prostate Cancer Prevention Trial (PCPT)
Principal Investigators (PIs):
- Catherine Tangen, Dr.P.H.
Fred Hutchinson Cancer Research Center
- Ian Thompson, M.D.
University of Texas Health Science Center, San Antonio
Funded Since: 1992
Funding Source: National Cancer Institute
Year(s) of Enrollment: 1993-1997
Study Website: http://www.swog.org/pcpt
The PCPT was undertaken to determine whether finasteride could reduce the prevalence of prostate cancer among initially healthy men aged 55 and older during a seven-year period. PCPT was a double-blind placebo controlled phase III trial that randomized 18,882 participants from sites in the U.S. and Canada. At study entry, men had a normal digital rectal exam (DRE) and a PSA ≤ 3.0 ng/dl. The men underwent annual DREs and measurements of PSA that were processed at a central lab. AUA symptom scores, clinically significant medical conditions (e.g., diabetes, cardiovascular outcomes, other cancers) and side effects were recorded. An extensive diet questionnaire was administered after the first year on study. Prostate biopsies were recommended during the trial for men with either an elevated PSA (> 4.0 ng/ml adjusted) or DRE suspicious for cancer. All men were recommended to have an end of study (EOS) biopsy regardless of their PSA level or DRE result. Tissue from all prostate biopsies was submitted to the Pathology Core Laboratory. Serum was collected annually and there was a white blood collection for which approximately 60% of the participants with a prostate cancer endpoint have a sample.
The PCPT was stopped 15 months earlier than planned. A 24.8% relative risk reduction in prostate cancer was observed with finasteride. However, tumors of Gleason grade 7-10 were more common in the finasteride group. All participant contact ended in June 2004. A Social Security Death Index search has been recently undertaken to evaluate long-term survival. By 2016, a National Death Index search will be conducted to obtain cause of death information.