How to treat diminutive polyps? Do we need more evidence?

THIEME The question of whether we manage polyps effectively has come to prominence because of the rates of interval or post-colonoscopy colorectal cancers, which range from 2.5 % to 10.7 % and which may in part be due to a failure to resect polyps completely (radically) [1, 2]. This issue was highlighted in the recently reported CARE (Complete Adenoma REsection) study of polyps 5 to 20 mm in size, which reported an overall rate of incomplete resection of 10 % [3]. However, the vast majority of polyps resected at colonoscopy (80 %) are 5 mm or smaller in size [4]. Although the rate of advanced disease on a per-polyp basis is low, the fact that small polyps are so common means that the absolute number of small polyps harboring advanced disease is comparable with the number of larger (6 – to 9-mm) polyps [5]. It is therefore possible that a reasonable percentage of interval cancers arise in diminutive polyps that have been nonradically, partially resected [2]. These lesions have traditionally been considered low risk, and therefore low risk methods to resect them – that is, cold techniques – have increasingly been favored. Hot biopsy is more difficult to justify, given the risks for bleeding and late perforation and the supportive data against hot biopsy derived from animal models [6, 7]. There is also a requirement to retrieve tissue for pathology to allow a determination of correct surveillance intervals ; however, retrieving small polyps is a challenge, and the use of hot techniques can lead to tissue destruction, rendering pathologic assessment impossible. Optical biopsy may help here because a diagnosis is potentially available for 100 % of detected polyps, whereas 17 % of small and diminutive le-sions may be lost or destroyed [8, 9]. Recent Euro-pean Society of Gastrointestinal Endoscopy guidelines support the limited use of optical biopsy for diminutive polyps in controlled circumstances and in expert hands, but community-based data suggest that this approach is not yet suitable for widespread implementation [8, 10]. Therefore, one option in expert hands may be not to treat some of these lesions at all and to leave them in situ, avoiding issues of resection risk, retrieval, and pathologic assessment as well as reducing costs—the DISCARD (Detect InSpect ChAracterise Resect and Discard) strategy [9], endorsed in the American Society for Gastrointesti-nal Endoscopy PIVI (Preservation and Incorporation of Valuable Endoscopic Innovations) statement [11]. Nevertheless, the majority …