An analysis of data from 1975 to 2010 found that overall colon cancer rates in the United States fell by about 1% each year during that time span. However, rates rose by 2% per year among those ages 20 to 34 and nearly .5% annually among those aged 35 to 49. It is unknown why rates are increasing in this group but the researchers believe that doctors “should be more aggressive investigating reports of minor rectal bleeding in younger adults, which is usually dismissed as hemorrhoids but may in fact indicate colorectal cancer.” JAMA Surgery, November 2014