Practical aspects of the management of precancerous lesions of the colon

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The guiding premise in Western society is that intervention in the 30% of adenoma-bearing subjects will prevent the 3% who currently die of colorectal cancer (CRC). Only 1% of GRC occur from familial adenomatous polypusis (FAP), and probably around 10 or 15% CRC have identifiable genetic risk, although the situation will clarify with the clinical availability of gene-probes. Cancer in ulcerative colitis is only a small risk overall, although a considerable anxiety for the endoscopist managing an individual patient in view of the unpredictability of mucosal dysplasia as a marker for cancer and the limitations of biopsy sampling. Once identified, any adenoma-bearing subject should have a careful total colonoscopy with potypectomies. Even lmn polyps can be seen with video-endoscopes, the resolution being still further increased with dye-contrast techniques. Flat adenomas appear to be uncommon in 1Vestern subjects. Surveillance strategies for adenomas have been over-emphasized; those with only one or more small adenoma(s) may not justify follow-up at all and infrequent surveillance (3-5 yearly) will be sufficient for most of the remainder, probably stopping around the age of 75 years. Large, multiple polyps indicate extra care in surveillance.
The smallest polyps are easily managed by the technique of "hot-biopsy", although delayed haemorrhage is a risk, especially for those taking aspirin. 5mm-2cm polyps are best managed by snaring but over this size pre-injection technique; snould be considered for safety (adrenaline only if sessile/short-stalked, adrenaline + sclerosant for large stalks). Bipolar and spiked snares have a place fur difficult sessile polyps, which may need piecemeal removal using a suction trap for specimen retrieval. Up to 100 polyps can be removed in a session if clinically indicated. Overall about 98% of polyps presenting at colonoscopy can be removed. The 1% of sessile polyps that are endoscopically too risky to remove may not justify surgery if the patient is elderly. Only the few malignant polyps that are poorly-differentiated or inadequately removed require subsequent operative resection. For the remainder, tattooing the polypectomy site and infrequent follow-up is all that is required.