Rising rates of colorectal cancer in younger adultsBMJ 2019; 365 doi: https://doi.org/10.1136/bmj.l4280 (Published 24 June 2019) Cite this as: BMJ 2019;365:l4280
- John D Potter, professor1 2
- 1Centre for Public Health Research Massey University, Wellington, New Zealand
- 2Fred Hutchinson Cancer Research Center, Seattle, WA, USA
The increase in rates of colorectal cancer among adults under 50 was first noted in 2003 but has only recently received attention.1 To understand the causes of this increase, it is useful to get the descriptive epidemiology clear, including the nature and consistency of the change; evidence of differences in young onset colorectal cancer by (more granular) age, sex, ethnicity, and other characteristics; and whether there are any historical parallel changes in other cancers for which we have plausible explanations.
Patterns of change
Studies in high income countries show that, although the overall incidence of colorectal cancer is falling everywhere except in Scandinavia, cases are rising among adults under 50 in nearly all countries studied.2345 The exception is Japan, which has among the highest rates of colorectal cancer in the world6 but has seen a fall in incidence among people under 50 since the early 1990s.7
In the US, rates of colorectal cancer began to rise earlier among adults …