These researchers found that 15% of men with a PSA level below 4.0 (commonly considered to be a normal level) had biopsy proven prostate cancer. This study calls further into question the usefulness of the PSA test. Current recommendations from the US Preventive Services Task Force do not recommend screening all men for prostate cancer using the PSA test.
Prevalence of Prostate Cancer among Men with a Prostate-Specific Antigen Level 4.0 ng per Milliliter
NEJM Volume 350:2239-2246 May 27, 2004 Number 22
Ian M. Thompson, M.D., Donna K. Pauler, Ph.D., Phyllis J. Goodman, M.S., Catherine M. Tangen, Dr.P.H., M. Scott Lucia, M.D., Howard L. Parnes, M.D., Lori M. Minasian, M.D., Leslie G. Ford, M.D., Scott M. Lippman, M.D., E. David Crawford, M.D., John J. Crowley, Ph.D., and Charles A. Coltman, Jr., M.D.
http://content.nejm.org/cgi/content/short/350/22/2239
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