Birth cohort effects in increase of early-onset colorectal cancer in four countries

Researchers at the International Agency for Research on Cancer (Lyon, France) investigated long-term incidence of early-onset colorectal cancer (eoCRC, diagnosed before age 50 years) in Australia, Canada, England, and the USA. All countries showed increasing eoCRC incidence in successivve birth cohort since 1960, with individuals born in the 1990s facing at least five-fold higher risks than those born in the 1960s. Over the most recent decade, estimated annual percentage change ranged from 3.6% in Canada to 6.0% in England, with steep rises before age 40 years. The authors conclude that these results suggest that contributing factors may originate early in life and accumulate througout the lifespan.