Thoughts on the prostate cancer findings in the PLCO Cancer Screening trial

The large NIH-sponsored PLCO (Prostate, Lung, Colorectal and Ovarian) Cancer Screening trial has produced some very interesting results this week regarding the overdiagnosis and potential overtreatment of prostate cancer and the utter lack of survival benefit from PSA screening for men (journal article here).

The PLCO study included more than 76,000 men across the United States who were followed up for a median of 11 years. The devil's advocate would say that probably isn't a long enough follow-up, since PSA elevation can precede clinically detected prostate cancer by 10 to 20 years. In addition, many (most) of the men in the control arm also had a PSA, which leads to decreased power of the study. (Aside: I'm digging the video Perspective Roundtable now available on The New England Journal of Medicine's web site. Here is one on screening for prostate cancer. But it is somewhat unsettling to see what these giants in the field of medicine actually look like after seeing their names on articles for years but not knowing them in person — kind of like seeing a radio DJ on TV, throws you for a loop.)

However, even with those caveats, this is a large, well done study that raises concerns about the benefit of PSA screening, at least as mortality in the first decade is concerned. I love this quote in the NIH news release about this study, which rang true to my geriatrician heart:

"What this report tells us is that there may be some men who are diagnosed with prostate cancer and have the side effects of treatment, such as impotence and incontinence, with little chance of benefit," said John E. Niederhuber, MD, director of the NCI.

I think the evidence that PSA is clearly beneficial is still missing, and certainly providers should very carefully consider all sides of the issue before routinely using PSA screening in their practices.