Cyclooxygenase-2 as target for chemopreventive interventions: new approaches.

Preventive medicine has become a corner stone in our concept of health in the third millennium. Colorectal cancer (CRC) fits the criteria of a disease suitable for prevention interventions. This is a prevalent disease that is associated with considerable mortality and morbidity rates. More than 1,000,000 new cases and 500,000 deaths are expected, worldwide, in 2005. CRC has a natural history of transition from precursor to malignant lesion that spans, on average, 15-20 years, providing a window of opportunity for effective interventions and prevention. A pre-malignant precursor lesion (i.e., adenoma) usually precedes cancer, and helps to identify a subset of the population that is at increased risk of harboring and developing cancer. Science and technology have evolved to a point where we are able to use our knowledge of cancer biology to identify individuals at risk. Since compliance with current screening methods is a major barrier to the achievement of optimal results, a large part of the average risk population has not been screened by any method. Hence, chemoprevention, a new science that has emerged during the last decade, presents an alternative approach to reducing mortality from CRC.