[Endoscopic resection of colorectal lesions--technique and indication]

As Screening programs for colorectal cancer become more popular in Japan, there are increasing opportunities for endoscopic resection of colorectal polyps. Indications for colorectal polyps is expanding because of new endoscopic resection technics. General indications for snare polypectomy include pedunculated or semipedunculated polyps. However, hot biopsy technique is occasionally employed for removing small sessile polyps, strip biopsy for superficial lesions (depressed or flat lesions), and piecemeal polypectomy for large sessile polyps or spreading superficial lesions. Endoscopic resection is usually performed to excise sessile or pedunculated lesions up to 2 cm in size or superficial lesions up to 1.5 cm in size. Large sessile or semipedunculated lesions over 2 cm in size should be treated by piecemeal polypectomy. The most controversial point of piecemeal polypectomy is difficulty in accurately orienting histological specimens. Additional surgical operation is necessary for sessile or pedunculated lesions histologically diagnosed that depth of invasion is over submucosa 1, or superficial lesions histologically diagnosed that depth of invasion is over mucosa.