Lifting of lesions during endoscopic mucosal resection (EMR) of early colorectal cancer: implications for the assessment of resectability

BACKGROUND AND STUDY AIMS: This study assessed the indications for and limitations of endoscopic mucosal resection (EMR) for early colorectal cancer, focusing on the way in which the lesion lifts after submucosal injection. PATIENTS AND METHODS: The study included 94 patients with early colorectal cancer who received EMR treatment. The lifting of the lesion after submucosal injection was analyzed (classified as completely lifted/soft; completely lifted/hard; incompletely lifted; and non-lifted) along with the endoscopic findings, pathological findings, and clinical course. RESULTS: Almost all completely lifted/soft lesions were mucosal cancers. Some of the completely lifted/hard lesions were staged as sm2. The incompletely lifted lesions included stages sm1 to sm3. Non-lifting lesions were almost always deeper than sm3. The lifting condition was significantly associated with the depth of invasion, and the lesion type was related to the extent of lifting but not to tumor size or recurrent disease. Recurrent disease was noted in three patients who underwent piecemeal EMR. CONCLUSIONS: The indication for EMR is easily assessed on the basis of the lifting characteristics of the tumor after submucosal injection, which was found to be significantly related to the depth of invasion. The factor limiting the indication for EMR is not the size of a tumor, but its lifting condition.