This week the American Cancer Society published its annual review of cancer statistics and trends. This year the big picture was overwhelmingly positive.
The three most frequently diagnosed cancers in men are prostate cancer, lung cancer, and colorectal cancer (in that order). For women the top three are breast, lung and colorectal cancer. (See the link below to Figure 1 in the study for details.) The incidences (the numbers of new diagnoses every year) of all of these cancers have decreased in the last few years, except for lung cancer in women, which is still increasing but at a slower rate than previously.
The continued decline in lung cancer in men is attributed to the decrease in smoking in men in the last few decades. Women, on the other hand, started smoking in significant numbers later than men in the twentieth century, but also continued to smoke after men were quitting. The peak of number of women smokers was 20 years after the peak for men, so the decline in lung cancer in women hasn’t happened yet (but will).
Colon cancer incidence continues to fall in both men and women, likely because of increased colon cancer screening with colonoscopy, leading to the removal of pre-malignant polyps.
In terms of deaths caused by cancer, the top four causes for men are (in order) lung, prostate, colorectal and pancreas. For women the top four are lung, breast, colorectal and pancreas. Note that prostate cancer and breast cancer are the most common causes of cancer in men and women, but since they are very treatable and sometimes even curable, they are only the second most common causes of cancer death. The opposite case is pancreatic cancer. It is the tenth most common cause of cancer, but because it is so frequently fatal, it is the fourth most common cause of cancer death.
Fortunately, the mortality rates from lung, breast, prostate and colorectal cancer are all falling, likely due to improvements in diagnosis and treatment. So over all, fewer Americans are dying of cancer due largely to advances in the treatments for these top four killers. Interestingly, mortality from pancreatic cancer has not changed dramatically, making me wonder whether it will overtake colon cancer as the trends continue.
During the same years in which these positive trends were occurring in cancer, major advances were also being made in heart disease. Because of improved treatments for blood pressure and cholesterol, and because fewer Americans are smoking, the mortality from heart disease has been falling for many years. Heart disease is still the most common cause of death in the US, with cancer a close second. Because of the drop in heart disease mortality, cancer is now the leading cause of death for those 85 and younger. (See the link below to Figure 6 for details.)
That’s all very encouraging news, except that it probably means that our children will all die of pancreatic cancer or Alzheimer’s disease. Perhaps our grandchildren will return to smoking…
American Cancer Society article: Cancer Statistics, 2010
Reuters article: U.S. cancer death rates continue drop: report