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© A N D R EI _R / SH U TT ER ST O C K .C O M A fter falling for decades, mortality rates for adult colorectal cancer (CRC) have increased in individuals aged younger than 55 years since the mid-2000s, according to a new report in the Journal of the American Medical Association.1 The finding, which was confined to white individuals, strengthens evidence that previous reports of CRC mortality increases in this age group are not just the result of increased screening. Researchers at the American Cancer Society previously reported that CRC has been increasing in the United States among white men and women aged younger than 55 years since the 1990s. The largest increase is in metastatic disease. At the same time, CRC mortality overall is rapidly declining, which masks the increasing trend among young adults, researchers say. They add that this increase has not been comprehensively examined. Lead study author Rebecca Siegel, MPH, of the American Cancer Society, and colleagues analyzed CRC mortality among individuals aged 20 to 54 years of age by race from 1970 to 2014, using data from the National Center for Health Statistics. The study included 242,637 individuals who died of CRC during that time period. Findings demonstrated that mortality rates in this age group declined from 6.3 per 100,000 population in 1970 to 3.9 per 100,000 population in 2004, which was when mortality rates began to increase by 1% annually, reaching 4.3 per 100,000 population in 2014. That increase was confined to white individuals, among whom mortality rates increased by 1.4% per year, from 3.6 per 100,000 population in 2004 to 4.1 per 100,000 population in 2014. Mortality rates for black individuals declined during the study period at a rate of 0.4% to 1.1% annually, from 8.1 per 100,000 population in 1970 to 6.1 per 100,000 population in 2014. In a combined group of other races, mortality rates declined from 1970 to 2006, and remained stable after that time. Although mortality rates remained stable in white individuals aged 20 to 29 years from 1988 to 2014, the following increases were observed: 1.6% per year from 1995 to 2014 in those aged 30 to 39 years, 1.9% per year from 2005 to 2014 for those aged 40 to 49 years, and 0.9% per year for those aged 50 to 54 years. Among black individuals, rates declined in every age group. The authors note that these disparate patterns by race are inconsistent with trends in major risk factors for CRC such as obesity, which is increasing among all observed racial groups. The authors note that rising CRC mortality rates among individuals in their 50s were unexpected because for decades, screening, which can prevent and detect cancer at earlier, more treatable stages, has been recommended starting at 50 years of age. Although screening prevalence has increased for all groups aged older than 50 years, it is lower for individuals aged 50 to 54 years compared with those aged 55 years and older: 44% versus 62%, respectively, in 2013, according to the National Health Interview Survey. The authors add that although the risk of CRC remains low for young and middle-aged adults, rising mortality rates indicate that the increase in incidence is not only the result of earlier detection of the disease. Instead, their findings point to “a perplexing escalation in disease occurrence,” they say. Furthermore, the increasing mortality rates for individuals aged 50 to 54 years led the authors to point to the need for more interventions to increase the use of age-appropriate screening, as well as the timely follow-up of symptoms.