病理から見た外来内視鏡治療の課題と要望

Challenges and requirements for endoscopic day surgeries: pathological viewpoint

要旨

外来内視鏡治療において，従来の内視鏡的ポリ―プ切除では，hot snare polypectomy（HSP）やEMRなどの高周波切開凝固装置を用いる治療が主流であったが，近年，高周波切開凝固装置を用いないcold polypectomy（cold snare polypectomy：CSP）やcold forceps polypectomy（CFP）が普及してきている。CSP/CFPは出血・穿孔などの偶発症が少なく，比較的短時間かつ簡便に行うことができ，clean colonの観点からは大きな利点があるものの，小さなポリープにおいても低頻度ながら癌または高異型度腺腫が含まれるのも事実であり，cold polypectomyの適応については微小癌の可能性を鑑別したうえで適切に実施していくことが重要と考えられる。本稿では，従来の高周波切開凝固装置を用いたポリープ切除HSP/EMRと高周波切開凝固装置を使用しないCSP/CFPの病理像を提示・比較しつつ，病理学的立場から，外来内視鏡治療に関わる全般的な課題や留意すべきポイントについて概説したい。

In conventional endoscopic polypectomy, hot snare polypectomy (HSP) and endoscopic mucosal resection (EMR) using high-frequency incisional coagulation devices have been the mainstream of endoscopic polypectomy methods for outpatients. In recent years, cold polypectomy has become more popular due to its simplicity and fewer complications. Cold polypectomy includes cold snare polypectomy (CSP) and cold forceps polypectomy (CFP), both of which do not involve electric current. However, it is also true that even small polyps may contain cancer or high-grade adenoma, although the frequency is low. Considering the disadvantages of cold polypectomy, it is important to rule out the possibility of carcinoma before endoscopic polypectomy. In this section, we present representative pathological images of polypectomy specimens using conventional HSP/HB and EMR as well as CSP/CFP, and outline the general issues and points to be noted regarding outpatient endoscopic treatment from a pathological standpoint.