A. Kuellmer et al., University Medical Center Freiburg, Germany, conducted a multicenter, retrospective study aiming to evaluate efficacy, safety and clinical value of EFTR for early colorectal cancer. Current international guidelines recommend endoscopic resection for T1 colorectal cancer with low-risk histology features and oncologic resection for those at high risk of lymphatic metastasis. Exact risk stratification is therefore crucial to avoid under-treatment as well as over-treatment.
Records of 1234 patients undergoing EFTR for various indications at 96 centers were screened for eligibility. A total of 156 patients with histologic evidence of adenocarcinoma were identified. This cohort included 64 cases undergoing EFTR after incomplete resection of a malignant polyp (group 1) and 92 non-lifting lesions (group 2).

Technical success was achieved in 144/156 patients (92.3 %). Mean procedural time was 42 minutes. R0 resection was achieved in 112/156 patients (71.8 %). A subgroup-analysis was performed assessing the R0 resection rate for subgroup 1 (previous incompletely resected malignant polyps, n=64) and subgroup 2 (non-lifting lesions, n=92). In group 1, a R0 resection rate of 87.5 % and in group 2 a R0 resection rate of 60.9 % had been reached (p<0.001).

Severe procedure-related adverse events (all perforations) were recorded in 6 cases (3.9 % of patients). One perforation was diagnosed immediately during the intervention and closed successfully with an over-the-scope clip. Five secondary perforations were observed after 1-8 days and required surgical intervention. Discrimination between high-risk versus low-risk tumor was successful in 155/156 cases (99.3 %). In group 1, 84.1 % were identified as low-risk lesions, whereas 16.3 % in group 2 had low-risk features. In total, 53 patients (34 %) underwent oncologic resection due to high-risk features. 98 patients (62 %) were followed endoscopically.

The authors concluded that in colorectal cancer, EFTR is technically feasible, effective and safe. It allows exact histological risk stratification and can avoid surgery for low-risk lesions. Prospective studies are required to further define indications for EFTR in malignant colorectal lesions and to evaluate long-term outcome.