As reported in The Lancet Oncology by Sung et al, analysis of international population-based cancer registry data indicate an increase in incidence of colorectal cancer among younger persons (age < 50 years) in a majority of countries and territories examined.
Study Details
Colorectal cancer incidence data, including year of diagnosis, sex, and 5-year age group for 50 countries and territories, were extracted from the World Health Organization–International Agency for Research on Cancer Cancer Incidence in Five Continents Plus database. Age-standardized incidence rates (ASRs) per 100,000 person-years were calculated for early-onset disease (diagnosed at age 25–49 years) and late-onset disease (diagnosed at 50–74 years). Average annual percentage changes (AAPCs) were estimated.
Key Findings
In the 5 most recent years (2013–2017 for the vast majority of countries), the ASRs for early-onset disease were highest in Australia (16.5, 95% confidence interval [CI] = 16.1–16.9), Puerto Rico (15.2, 95 CI = 14.2–16.2), New Zealand (14.8, 95% CI = 14.0–15.6), the United States (14.8, 95% CI = 14.7–14.9), and South Korea (14.3, 95% CI = 14.0–14.5); they were lowest in Uganda (4.4, 95% CI = 3.6–5.2) and India (3.5, 95% CI = 3.3–3.7). The ASRs for late-onset disease were highest in the Netherlands (168.4, 95% CI = 166.9–170.0) and Denmark (158.3, 95% CI = 155.8–160.9) and lowest in Uganda (45.9, 95% CI = 38.5–51.4) and India (23.5, 95% CI = 22.8–24.3).
In the 10 most recent years, AAPCs for early-onset disease were stable in 23 countries and increased in 27 countries. The greatest AAPC increases for early-onset disease were in New Zealand (3.97%, 95% CI = 2.44%–5.52%), Chile (3.96%, 95% CI = 1.26%–67.4%), Puerto Rico (3.81%, 95% CI = 2.68%–4.96%), and England (3.59%, 95% CI = 3.12%–4.06%). Of the 27 countries with increased AAPCs for early-onset disease, 14 had stable AAPCs for older-onset disease (Argentina, France, Ireland, Norway, and Puerto Rico) or decreasing AAPCs (Australia, Canada, Germany, Israel, New Zealand, Slovenia, England, Scotland, and the United States). Among 13 countries with increasing AAPCs in both age groups, AAPCs for younger vs older patients were higher in Chile, Japan, Sweden, the Netherlands, Croatia, and Finland; lower in Thailand, France (Martinique), Denmark, and Costa Rica; and similar in Turkey, Ecuador, and Belarus. The increase in early-onset colorectal cancer was faster among men vs women in Chile, Puerto Rico, Argentina, Ecuador, Thailand, Sweden, Israel, and Croatia and faster among women vs men in England, Norway, Australia, Turkey, Costa Rica, and Scotland.
The investigators concluded: “Early-onset colorectal cancer incidence rates are rising in 27 of 50 countries and territories examined, with the rise either exclusive to early-onset disease or faster than the increase in older adults in 20 of the 27 countries. The findings underscore the need for intensified efforts to identify factors driving these trends and increase awareness to help facilitate early detection.”
Hyuna Sung, PhD, of the American Cancer Society, Atlanta, is the corresponding author of The Lancet Oncology article.
Disclosure: The study was funded by the Intramural Research Program of the American Cancer Society, Cancer Grand Challenges, and National Institutes of Health. For full disclosures of the study authors, visit the lancet.com.
