Incidence Rate
The incidence rate for colon and rectal cancer among Asian/Pacific Islanders (from 2002 to 2006) was 46.9 per 100,000 men and 34.6 per 100,000 women. See the National Cancer Institute’s SEER Stat Fact Sheet for more information
Mortality Rates
Mortality rates among Asian/Pacific Islanders were 13.8 per 100,000 men and 10.0 per 100,000 women. Both incidence and mortality rates were lower compared with White or Black populations in the U.S.
Differences Among Subgroups
Among Chinese living in various countries, the variable rates suggest diet related and other environmental risk factors for colon cancer. The rates are higher among U.S. and Hong Kong Chinese than in mainland China. There are no specific and time-correlated studies of cancer incidence across various Chinese subgroups. But Cao et al (2009) reported data on colorectal cancer patients during 2000-2002 that were collected from Guangzhou’s population-based cancer registry. They found the crude incidence of colon cancer to be 13.4 per 100,000 (13.5 per 100,000 in males, 13.3 per 100,000 in females), and the crude incidence of rectal cancer to be 9.6 per 100,000 (10.8 per 100,000 in males, 8.2 per 100,000 in females).
In terms of mortality of colon cancer, the rate was 7.1 per 100,000 (7.3 per 100,000 in males, 6.9 per 100,000 in females). The mortality rate for rectal cancer was 5.0 per 100,000 (5.5 per 100,000 in males, 4.5 per 100,000 in females).
Colorectal Neoplasia
Chiu et al. (2005) conducted a study in Taiwan, to determine the frequency of colorectal neoplasia in an asymptomatic Taiwanese population and the topographic distribution of lesions relative to age and gender. Of 1741 (94.3%) patients (1041 men, 700 women; mean 52.5 years) enrolled, 1708 (98.1%) underwent total colonoscopy. The authors found that 263 (15.4%) had colorectal neoplasia and 51 (3.0%) had advanced lesions.
Risk Factors
In terms of risk factors, Murphy et al (2009) examined the association of family history of cancer and subsequent colorectal cancer risk in a cohort of traditionally low-risk Chinese women. They followed 73,358 women in the Shanghai Women’s Health Study for cancer incidence. After an average of 7 years of follow-up, 391 women were diagnosed with colorectal cancer. They adjusted the data for age, smoking, family income, education, body mass index, physical activity, and history of diabetes. The authors found a significant association between colorectal cancer risk and history of a parent being diagnosed with colorectal cancer (hazard ratio: 3.34; 95% confidence interval: 1.58, 7.06).
Influence of Family History
No association was observed for colorectal cancer diagnosed among siblings. Also, colorectal cancer risk was not influenced by a positive family history of cancer generally or any of the other cancers investigated (lung, breast, prostate, gastric, esophageal, endometrial, ovarian, urinary tract, central nervous system, and small bowel). These cohort results suggest that consistent with findings from Western populations, having a family history of colorectal cancer may influence colorectal cancer risk to a similar extent in a low-risk population.
