Characterization and Identification of Colorectal Cancer in Persons Younger Than 50 Years.

The proportion of colorectal cancer (CRC) cases in persons younger than age 50, referred to as early onset CRC (EOCRC), has increased from 6% to 11% over the past 25 years, whereas the incidence of CRC has decreased in persons age 50 and older, referred to as late-onset CRC (LOCRC) in the United States.1 It is not known if EOCRC is caused by the same factors that cause LOCRC, or whether there are unique causes that alter the clinical features.2 This study was designed to analyze the clinical and genetic characteristics of EOCRC as presented at a community hospital.