Epidemiology of colorectal cancer in Asia.
The prevalence of colorectal cancer is increasing in Asia. However, the age-standardized rate has reached a plateau in some countries. Some studies have shown a male predominance difference and increasing risk in the elderly, but not in the younger population. 'Right shifting' of colorectal cancer, not accountable by difference in age or the indications for endoscopic examination, has also been noted. Westernized diet is associated with colorectal cancer, but controversy remains on how it causes colorectal cancer. Alcohol consumption, obesity, diabetes mellitus, consumption of red and processed meat and cigarette smoking are linked to bowel cancer epidemiologically. Only high dietary calcium has a consistent negative (or 'protective') effect. The efficacy of fish oil, vitamin D, soy, phytoestrogens, folate, methionine, riboflavin and vitamin B6 has not been established. Aspirin and non-steroidal anti-inflammatory drugs use decrease risk of colorectal cancer after 5-10 years of use. There is no evidence for a detrimental effect of proton pump inhibitors or benefit of statins in colorectal cancer. In conclusion, there is a rising trend and prevalence of colorectal cancer in Asia. Dietary modification or supplementation may not be effective in preventing colorectal cancer. Surveillance of colorectal cancer in high-risk groups, according to current recommendation, is probably most effective.
Yee
Yuk Kei
YK
Medicare Endoscopy Centre, The University of Hong Kong, Hong Kong.
Tan
Victoria P Y
VP
Chan
Pierre
P
Hung
Ivan F N
IF
Pang
Roberta
R
Wong
Benjamin C Y
BC
D017677:Age Distribution; D016588:Anticarcinogenic Agents / Q000008:administration & dosage; D001208:Asia / Q000453:epidemiology; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D004032:Diet / Q000009:adverse effects; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods; D015995:Prevalence; D018570:Risk Assessment; D012307:Risk Factors; D040242:Risk Reduction Behavior; D017678:Sex Distribution; D013997:Time Factors
D016588:Anticarcinogenic Agents