Colorectal Cancers are Falling

Bob Hatcher

April 9, 2016

          In 2016 about 134,000 people in the United States will be found to have colorectal cancer and 49,000 will die from this type of cancer.  

          Adenomas of the colon are estimated to be present in 20 to 53% of the US population older than 50 years of age but only .2 to 0.6% of these are adenocarcinomas. Williamson Strum in the March  17, 2016, edition of the New England Journal of Medicine notes that adults in the United States have an approximately 5% lifetime risk of developing adencocarcinoma. If one considers deaths in both men and women, colorectal cancers are the second highest cause of death from cancer.

          The number of cases of colorectal cancer and deaths from colorectal CA have been falling every single year in women since 1947 and in men since 1980. The colorectal cancer story is high on the list of cancer success stories in our country.

          The story could be even better were early detection achieved more consistently. If cancer is localized when diagnosed the 5 year survival rate is 90% but only 39% of patients are diagnosed at this early stage.  Overall the 5 year survival rate for colorectal cancer is 65%.

Here are the factors lowering a person’s risk for colorectal cancer suggested by the American Cancer Society:

  • not smoking
  • using nonsteroidal anti inflammatory agents (low dose aspirin) lowers risk for colorectal CA beause it leads to bleeding from early colorectal lesions and early treatment of them. .
  • regular (each 10 years for most people) colonoscopy screening starting at age 50 and stopping at age 75 unless at higher risk for colorectal cancer (see below) . Stool screening for occult blood should be done each 3 years.

Other risk reducing approaches are:

  • for women, prolonged use of contraceptive steroids (birth control pills, patches and rings).
  • for men and women: ingestion of coffee. Consumption of decaffeinated coffee, is associated with a reduced incidence of rectal cancer.[Journal of the National Cancer Institute, 97, No. 4, © Oxford University Press 2005.
  • A large analysis of the effects of high fiber diets was reviewed in 2011 in the British Journal of Medicine. Their summary: Our results indicate a 10% reduction in risk of colorectal cancer for each 10 g/day intake of total dietary fiber and cereal fiber and a about a 20% reduction for each three servings (90 g/day) of whole grain daily, and further reductions with higher intake. These findings thus have important public health implications. Our results suggest a particular benefit of increasing cereal fiber and whole grain intake. Increasing the intake of dietary fiber and whole grains is also likely to reduce the risk of cardiovascular disease,type 2 diabetes, overweight and obesity, – ref-72 and possibly overall mortality 

If you are at an increased risk of colorectal cancer, you might need to start colorectal cancer screening before age 50 and/or be screened more often and to an older age. The following conditions make your risk higher than average:

  • A personal history of colorectal cancer or adenomatous polyps
  • A personal history of inflammatory bowel disease (ulcerative colitis or Crohn’s disease)
  • A strong family history of colorectal cancer or polyps
  • A known family history of a hereditary colorectal cancer syndrome.