I’m going to open with the journey that led to this post. It started with this post by John Horgan questioning the U. S. Prevention Services’s updated guidelines on early breast cancer screening. Basically, his conclusion is that the new guidance may actually lead to more deaths which appears to be the inference derived from the service’s own data. That led to this post of his on cancer mortality which in turn led to the graph at the top of the page from Our World in Data.
I wish the graph had been updated to the present day. Twelve years can be an eternity. I also wish the graph had been adjusted for age. As a pathologist buddy of mine observes everybody dies of something. If heart disease doesn’t get you cancer will.
Several things jumped out at me from the graph and I wanted to reflect on those. The most obvious is that less smoking has resulted in an enormous difference in the mortality due to lung cancer. It probably has reduced mortality due to other forms as well. But that isn’t the only thing.
Note that death rates for several forms of cancer (pancreas, leukemia) were increasing until the mid-1960s and have plateaued since then. I would speculate that the adoption of Medicare/Medicaid resulted in a decline in cancer deaths.
Several cancers (breast cancer in women, prostate cancer in men, colo-rectal cancer) show sharp declines in mortality in the 1990s. In the cast of prostate cancer I can only speculate the approval of the PSA test was instrumental. There may be a similar factor in breast cancer in women. Routine colonoscopies may be related to the declines in mortality from that cause. All of those would seem to contradict Mr. Horgan’s observations.
Mortality due to liver cancer, stomach cancer, and uterine cancer has been decreasing for a long time—over the last century. Mortality due to liver cancer in men, bucking the trends, has actually increased since 1980. I have no explanation for that. I would suspect it is behavioral or environmental.







