A new study finds colorectal cancer incidence rates for both males and females increased in 27 of 51 countries worldwide between 1983 and 2002, and points to increasing Westernization as being a likely culprit.
The rise was seen primarily in economically transitioning countries including Eastern European countries, most parts of Asia, and some countries of South America. The study is the first in a peer-reviewed journal to present colorectal cancer incidence trends across all five continents. It appears in the June 2009 issue of Cancer Epidemiology Biomarkers and Prevention. An accompanying editorial says the rise points toward a failed early detection and prevention strategy as well as failure to address lifestyle and dietary challenges of urbanization that affect most of the globe.
Colorectal cancer is the fourth most common cancer in men and the third most common cancer in women worldwide. Previous studies have reported rapid increases in colorectal cancer incidence rates in economically transitioning countries in many parts of the world, likely reflecting changing dietary and physical activity patterns. However, those studies used old data and examined regional or country-specific trends. The new study, led by American Cancer Society epidemiologist Melissa Center, MPH, reviewed colorectal cancer incidence data from 51 cancer registries worldwide with long-term incidence data from the Cancer Incidence in Five Continents (CI5) databases created by the International Agency for Research on Cancer (IARC). Researchers analyzed the change in incidence rates over the past 20 years; 1983-87 through 1998-2002.
They found colorectal cancer incidence rates for both males and females increased for 27 of 51 cancer registries considered in the analysis between 1983-87 and 1998-2002. The increases were more prominent for men than for women. Some of the increases were dramatic. For example, in Slovenia, colorectal cancer incidence increased 70 percent among men and 28 percent among women. In Miyagi, Japan, rates rose 92 percent among men and 47 percent among women.