Figure 1.

A schematic representation of the Paris classification for mucosal neoplasia. Lesion morphology helps in the evaluation of the risk of invasive disease and guides the approach to endoscopic resection. Advanced mucosal neoplasias are broadly divided into protruded, flat elevated, and flat morphologies. Protruded lesions rise more than 2.5 mm above the surrounding mucosa and include pedunculated (0-Ip), subpedunculated (0-Isp), and sessile (0-Is) lesions. Flat elevated lesions (0-IIa) rise less than 2.5 mm above the surrounding mucosa, and features such as central depression (0-IIa + c) or a broad-based nodule (0-IIa + Is) have been described. Flat lesions include barely perceptible elevation (0-IIb), depressed (0-IIc), and excavated (0-III) types.

Reproduced with permission from Holt BA, Bourke MJ. Wide field endoscopic resection for advanced colonic mucosal neoplasia: current status and future directions. Clin Gastroenterol Hepatol. 2012;10(9):969-979.