Prostate cancer is often detected using prostate specific antigen (PSA) screening. Now, a new study reveals, despite the cancers status as the leading cause of cancer death in American men, there is little reason to screen men more often than every four years.
Researchers in Amsterdam wanted to know if screening every two years would save more lives than screening every four years. The effectiveness of a cancer screening method is not just judged by the number of cancers detected; physicians must take into account if more people with the cancer diagnosis are actually surviving and how many cancers are picked up between screenings, called interval cancers.
More prostate cancers were detected in men screened every two years than men screened every four years, report researchers. The more frequent screenings, however, did not reduce the number of aggressive cancers found between scheduled screenings, meaning the more frequent tests did not actually find more of the deadlier forms of the disease.
For the study, 4,202 men were screened every two years, and 13,301 men were screened every four years. Over the next 10 years, 13.14 percent of the men screened every two years were diagnosed with cancer while 8.4 percent of the men screened every four years received a diagnosis. Researchers report the percentages of interval cancers diagnosed in each group are not significantly different, and the two-year screening program did not reduce the number of interval cancers as expected.
Study authors write screenings seem to have equal effectiveness whether men are tested every two years or every four years, though the more frequent screenings may turn up more minor cancers.
SOURCE: Journal of the National Cancer Institute, 2007;99:1296-1303