4. Difficult polypectomy

This chapter describes various techniques that can be employed to assist in the removal of colon polyps that are considered to be large or ‘difficult.’ Size alone is only one of the features that may cause some hesitation in making the decision to attempt polyp removal. Other factors that are related to the perceived level of difficulty are polyps that are flat and only slightly elevated above the mucosal surface, location on a wall of the colon that is not accessible to the snare, a polyp in a segment of severe diverticular disease or wrapped around a fold in clam-shell fashion. A polyp situated behind a fold can be difficult to approach, and those in the cecum hidden behind the ileocecal valve present a special challenge for resection. These and other problems will be addressed in this chapter as will the localization of lesions or polypectomy sites for future surgery (in the case of malignant polyps) or for reevaluation following total or incomplete polyp removal. The impossible polyp is one which the endoscopist feels cannot be removed. The feeling of futility when faced with such a polyp is directly dependent on the training, experience, and courage of the endoscopist. What may be ‘impossible’ for one endoscopist may be a relatively ‘routine’ polypectomy for another. In general, there are three criteria that make a polyp ‘impossible’, and when the three occur in the same lesion, then the polyp may be ‘really impossible’. The three factors which by themselves or in combination with others may place the polyp in an ‘impossible’ category are size, location of the polyp, and configuration.