The specter of colon cancer is legitimately frightening. However, some experts are starting to be concerned that doctors and patients are too worried, and are performing unnecessary and precautionary procedures to avoid it in circumstances in which colon cancer really isn’t a significant risk—procedures that may actually be dangerous in themselves.
Colon cancer screening is on the rise. Screening generally means looking for growths called polyps, and as more people are being screened more often, doctors are finding more polyps, generally of a type called adenomas. Current treatment guidelines urge that all adenomas be removed surgically when found, but studies show that only about five percent of them develop into cancer, and that could take decades to happen.
In fact, more and more doctors are removing other types of polyps, even when that entails a more difficult or more dangerous procedure. Adenomas can often be removed with a simple wire loop during the screening procedure itself, but other types require more elaborate surgery. Moreover, some other types of polyps are not as well understood than adenomas, and may not even carry a significant cancer risk. One estimate is that only a quarter of a percent of all polyps—rather than just adenomas—are potentially malignant, meaning in many cases, it is safer to leave them alone than to remove them.
The hard part is knowing which ones are dangerous. Colon cancer far more likely to be successfully treated if treatment begins early, and removing polyps that will develop into cancer before they do so is the earliest treatment there is. So not removing any is not an adequate solution either. What this does mean is that people who have had polyps, whether or not they were removed, should be advised that they probably did not have a brush with death, and they should not think of themselves as living on borrowed time. This is particularly true for people who have no risk factors for colon cancer, healthy non-smokers under 50 with no history of cancer.