Robot-assisted Minimally Invasive Surgery (MIS) and Natural Orifice Transluminal Endoscopic Surgery (NOTES) are commonly adopted in Gastro-Intestinal (GI) cancer treatment with Endoscopic Submucosal Dissection (ESD). While using fully flexible cable-driven robots brings benefits to patients, the engineering challenges, for example, size and stiffness, manufacturability and sensorless environment, limit functionalities of robotic instruments and surgery performance. The rolling feature, rotation along the wrist of the instrument, is a good-to-have feature for surgical procedures with orientational and positional requirements such as tractioning and suturing with graspers. This paper aims to demonstrate a scalable distal joint rotation mechanism for continuum endoscopic robots that can increase instrument dexterity and manipulability to ease the work of surgeons.