In Searching of Colorectal Cancer Screening Tools Suitable for Resource-limited Countries

Abstract

Colorectal cancer (CRC) has traditionally been one of the commonest malignant disorders in western populations, whereas cancers of the upper gastro-intestinal tract (esophagus and stomach) and liver have predominated in the east. The last two decades has witnessed a dramatic rise in CRC incidence and mortality in Asia. The Asia Pacific region represents a diversified population with disparities in disease prevalence, health belief attitudes and healthcare infrastructure. Although CRC is considered to be closely related to environmental factors, particularly diet and lifestyle, effective methods for primary prevention have yet to be established. The best near-term option for decreasing the burden of CRC is therefore screening for early cancer and precancerous lesions. There is strong evidence that screening for colorectal cancer improves survival. Current international practice guidelines and expert consensus statements recommend CRC screening for people over 50 years. The public, in general, is poorly informed about the rising incidence of CRC and the benefits of screening tests. Financial constrains appear to be a major hurdle to implement screening program. Clinical studies showed that colonic neoplasms are predominantly found in the distal colon. Yet 50% of patients with proximal colonic lesions have normal distal colon. With the existing infrastructure and health care system, it would be very difficult, if not impossible, to perform CRC screening for the whole population older than 50 years of age. Among several modalities that have been proposed for colorectal cancer screening, the fecal occult blood test (FOBT) or Hemoccult test has been demonstrated in three landmark randomized controlled trials to reduce mortality from this cancer In Searching of Colorectal Cancer Screening Tools Suitable for Resource-limited Countries