Most of the folks who have commented on my blogs regarding screening have been pretty outspoken about their belief that screening should continue and that the US Preventive Services Task Force was wrong in recommending against screening. In support groups, as I have discussed, men seem to feel that either their lives were saved by screening or that had they been screened earlier they would have been cured. Both points of view may be true for a minority of individuals, but the individual experience does not reflect doing good for the whole population.
In today’s NEJM, an article by Bleyer finds a similar situation for the use of mammography. I can only imagine that the press will be all over this tomorrow and that the breast cancer advocates will be out in force, mostly with emotion, not data. So here are the data: “…we estimated that breast cancer was overdiagnosed (i.e., tumors were detected on screening that would never have led to clinical symptoms) in 1.3 million U.S. women in the past 30 years. We estimated that in 2008, breast cancer was overdiagnosed in more than 70,000 women; this accounted for 31% of all breast cancers diagnosed.” The data are illustrated in the following figure from the article:
The figure shows little change in the rate of late stage cancer, even though there is a huge increase in the number of early cases detected. If anything, the prostate cancer statistics are considerably better, and the prostate screening advocates argue that the real benefits won’t be seen for many more years. The number of cases of advanced prostate cancer has gone down since PSA screening was introduced, but without as much effect on prostate cancer deaths thus far. Of course if taking your prostate out had no side effects, we could all agree that removing everyone’s prostate after someone decided on no further reproduction could be a safe and reasonable procedure for all men – maybe like vasectomy. But, both breast cancer treatment and prostate cancer treatment clearly DO have side effects. So the answer isn’t so easy in my mind. I will mostly be interested in what the advocates do about this article, and I wonder when it isn’t so personal, whether men will have any different views of this cancer dilemma than of the prostate screening challenge.