An Ounce of Prevention…

Cancer screening saves lives. This is because early detection means a better chance at effective treatment. Current technologies such as mammograms and colonoscopies have become standard procedure in attempts to diagnose cancers as early in their progression as possible.

These tools detect a cancerous growth in the early stages of development. Although these diagnostics will remain important, researchers and physicians alike are becoming increasingly interested in an even more sensitive means of predicting who is at risk for developing certain types of cancer – using genetic data to determine if a patient is at higher than average risk of developing a particular cancer. Various genes have already been linked with an increased risk of different types of cancer, including ovary, breast, skin, pancreatic, and colon cancer.

Knowing that you are at increased genetic risk for a particular type of cancer affords the opportunity to be especially vigilant about regular screenings. Increasingly, it may also enable people to take advantage of chemopreventive agents – drugs taken for the purpose of preventing, rather than treating, cancer. Although pharmaceutical-based chemopreventive strategies have been used for several years, a number of studies have recently been reported confirming the practice. A study presented at the Frontiers of Cancer Prevention Research conference last fall showed a 63% reduction in breast cancer amongst high-risk women treated prophylactically with tamoxifen. Another drug, iloprost, was reported to significantly reduce the appearance of abnormalities in cells lining the airways of former smokers. Perhaps most intriguing of all are the results of a long term study examining the chemopreventive effects of aspirin – that ubiquitous drug first used for simple aches and pains, and later recognized as a preventative for heart attacks and strokes in some populations. Dr. John Burn of Newcastle University recently published the results of a long term study examining patients at very high genetic risk for the development of colorectal cancer treated with aspirin. Subjects undergoing aspirin therapy showed a significant reduction in cancer rates when compared to those not treated with aspirin, with the results being especially pronounced in those who had taken aspirin for more than two years. Another study carried out by University of Oxford researcher Peter Rothwell suggest that daily doses of aspirin over several years can reduce the risk of dying from all types of cancers by 34%.

All of these drugs – even aspirin – have some side effects, which should certainly be taken into account when patients and physicians contemplate chemopreventive therapies. But for individuals at high or very high risk for developing cancer, knowledge is indeed power, and any tool available that will potentially mitigate risk factors should be considered.