Trends in colorectal cancer incidence and mortality

This article examines recent trends in the incidence of and mortality from colorectal cancer among Canadian men and women, then further analyzes trends by three subsites.

Incidence data for colorectal cancer were obtained from the National Cancer Incidence Reporting System and from the Canadian Cancer Registry. Mortality data were extracted from the Canadian Vital Statistics Database. Supplementary data on nutrition are from the National Population Health Survey.

Age-standardized incidence and mortality rates were calculated for men and women. Age-specific incidence and mortality rates were calculated by 10-year age groups. Joinpoint analysis was applied to detect statistically significant changes in linear trends.

Since the mid-1980s, colorectal cancer incidence has been declining, with steeper rates of decrease among women. Decreasing rates of colorectal cancer are limited to tumours located in the distal colon and rectum; the incidence of cancers of the proximal colon has not changed over time.