The latest results from the European Randomized Study of Screening for Prostate Cancer (ERSPC) found a lower risk of death due to prostate cancer in men screened using the PSA test, compared to men who were not screened. But unfortunately this finding does not offer clear guidance to American men trying to figure out what the great PSA testing debate means for them.
The current definitive trial for U.S. men is the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, which involved about 77,000 men aged 55 to 74. It found no clear benefit to PSA screening, but plenty of potential harms. These included repeated biopsies, the psychological impact of a cancer diagnosis, the side effects of treatment, and overdiagnosis of potentially unimportant cancers.
The ERSPC was also a large study, involving more than 162,000 men aged 55 to 69 in seven countries. However, important differences in how the European men were screened and treated mean its findings don’t apply well to the American population.
Also, the absolute benefit of PSA screening measured by the ERSPC trial is relatively small. It translates into a reduction from 3% to 2.4% in the lifetime risk of dying from prostate cancer. This modest gain comes at a steep cost: In the most recent update of the ERSPC, testing 1,055 men diagnosed an additional 37 cancers and prevented one death.
If you happen to be the man who survives cancer because of screening, that small benefit is tremendously significant. But with respect to public health policy in the United States, the PLCO results have cast doubt on the value of routine PSA testing. Some doctors no longer recommend it as part of a man’s annual medical check up.
“I tell patients we have the issue of overdiagnosis and overtreatment,” explains Dr. Marc B. Garnick, a clinical professor at the Harvard Medical School and a leading expert on PSA testing. “If you want to go through the PSA test, it leads to a slippery slope of being diagnosed. And there’s a reasonable chance that the cancer we find won’t even need to be treated, but there are complications associated with the biopsy and you are likely to require additional biopsies.”