Published online Dec 14, 2013. doi: 10.3748/wjg.v19.i46.8527
Revised: October 20, 2013
Accepted: November 3, 2013
Published online: December 14, 2013
Less than 5% of colorectal adenomas will become malignant, but we do not have sufficient knowledge about their natural course to target removal of these 5% only. Thus, 95% of polypectomies are a waste of time exposing patients to a small risk of complications. Recently, a new type of polyps, sessile serrated polyps, has attracted attention. Previously considered innocuous, they are now found to have molecular similarities to cancer and some guidelines recommend to have them removed. These lesions are often flat, covered by mucous, not easily seen and situated in the proximal colon where the bowel wall is thinner. Thus, polypectomy carries a higher risk of perforation than predominantly left-sided, stalked adenomas - and we do not know what is gained in terms of cancer prevention. Screening is a neat balance between harms and benefit for presumptively healthy participants not interested in risk exposure to obtain confirmation of being healthy. The situation is quite different for patient worried about symptom. Thus, the standards set for evidence-based practice may be higher for screening than for routine clinics - a mechanism which may benefit patients in the long run.
Core tip: There is a basic difference in incitements to attend for screening when you are healthy and for routine clinics when you are ill. This article points out logical mechanisms which may set standards for screening higher than for routine clinics, but this may prove to be of benefit for clinical services and patients in the long run. This is highlighted by sessile serrated polyps which were previously classified as innocuous hyperplastic polyps. Recent guidelines now recommend polypectomy of these lesions for cancer prevention, but we do not know the benefit gained - only the increased risk of perforation by polypectomy.