Global Increasing Incidence of Young-Onset Colorectal Cancer Across 5 Continents: A Joinpoint Regression Analysis of...

Colorectal cancer incidence among young adults in the United States is on the rise, but whether this phenomenon is present in other parts of the world is not well documented. This study aims to explore the temporal change of incidence rates for colorectal cancer in various countries across the globe.

We extracted colorectal cancer incidence and population data from 1988 to 2007 based on data from the International Agency for Research on Cancer and compared incidence between age groups. Twelve representative jurisdictions from five continents were selected. Young-onset colorectal cancer cases were defined as those ages <50 years. Joinpoint regression was used to measure the trends of colorectal cancer incidence and to estimate the annual percent change (APC).

The APC for those ages <50 years was noted to be increasing at a faster rate as compared with those ages ≥50 years in many regions, including Australia (+1.10% vs. -0.35%), Brazil (+9.20% vs. +5.72%), Canada (+2.60% vs. -0.91%), China-Hong Kong (+1.82% vs. -0.10%), China-Shanghai (+1.13% vs. -2.68%), Japan (+2.63% vs. +0.90%), the United Kingdom (+3.33% vs. +0.77%), and the United States (+1.98% vs. -2.88%). These trends were largely driven by rectal cancer, except in Brazil and the United Kingdom.

Increasing incidence of young-onset colorectal cancer was noted in many regions across the globe.

Further studies focusing on young-onset colorectal cancer, particularly with regard to risk factors and establishing the optimal age of screening, are warranted.