Background Rectal endoscopic full- thickness dissection (EFTD) using a fexible colonoscope is an alternative to the wellestablished trans-anal endoscopic microsurgery (TEM) and the trans-anal minimally invasive surgery (TAMIS) techniques for resecting dysplastic or malignant rectal lesions. This study evaluated EFTD safety by analyzing outcomes of the frst patients to undergo rectal EFTD at the ...