ASGE guideline: The role of endoscopy in the diagnosis, staging, and management of colorectal cancer

For the following points: (A), prospective controlled trials; (B), observational studies; (C), expert opinion. • Colonoscopy is essential in the diagnosis of CRC. (B) • Multiple biopsy specimens should be obtained from all suspicious lesions, and polypoid lesions should be removed. (A) • EUS is accurate in the preoperative locoregional staging of rectal cancer and is useful in guiding therapy. (A) • Malignant colonic obstruction can be effectively treated endoscopically for palliation or as a bridge to surgery with SEMS or laser therapy. (B) • Unfavorable histopathologic factors of malignant colonic polyps associated with a high risk of lymph-node metastasis or local recurrence after endoscopic resection include the following: poorly differentiated histology, vascular or lymphatic invasion, cancer at the resection margin, and incomplete resection. (B) • Malignant pedunculated polyps confined to the submucosa can be considered to be adequately treated by endoscopic resection if removed completely and if there is no evidence of unfavorable histologic features. (B) • Malignant sessile polyps confined to the submucosa and demonstrating no evidence of unfavorable histologic factors have a small increased risk of lymph-node metastasis and local recurrence compared with similar pedunculated polyps after endoscopic resection. Endoscopic resection of this subset of sessile polyps may be adequate if the resection was complete and en bloc; however, surgical resection should be considered to ensure definitive treatment. (B) • HGD can be adequately treated with endoscopic resection. (B).