BACKGROUND: In this study, the authors evaluated the role of narrow band imaging endoscopy in the early detection of infiltration of the colon wall by flat and depressed lesions, highlighted during colonoscopy, to confirm the possibility of removal with Endoscopic Mucosal Resection (EMR). METHODS: 67 patients (37 males and 30 females) with non-polypoid colorectal lesions were included in this study. The location of the lesions, the size and possible infiltration of the colon wall were performed with a colonoscopy with NBI. Lesions without massive invasion were treated with an EMR. RESULTS: NBI was found to be a sensitive, specific, and accurate technique in assessing any infiltration of the colon wall. Endoscopic resection of the mucous membrane was successfully performed in 62 patients, it was not possible to perform it in 5 patients, due to the lack of dissection, and they underwent surgery. CONCLUSIONS: Non-polypoid colorectal lesions and early tumors can be treated with EMR. Certainly, early detection with Narrow Band Imaging endoscopy and subsequent endoscopic resection can reduce colorectal cancer mortality. Many studies have confirmed that these two methods have achieved important results comparable with surgical procedures.