Low value of second-look endoscopy for detecting residual colorectal cancer after endoscopic removal.

Background And Aims: Endoscopic resection is often feasible for submucosal invasive colorectal cancers (T1 CRCs) and usually judged as complete. If histology casts doubt on the radicality of resection margins, adjuvant surgical resection is advised, although residual intramural cancer is found in only 5% to 15% of patients. We assessed the sensitivity of biopsy specimens from the resection area for residual intramural cancer as a potential tool to estimate the preoperative risk of residual intramural cancer in patients without risk factors for lymph node metastasis (LNM).