Development of a new two-arm transurethral surgical system for en bloc resection of bladder tumor-A preclinical study

To overcome the piecemeal nature of bladder tumor resection, en bloc resection of bladder tumor (EBRT) has been introduced. ERBT is difficult for surgeons to perform using the currently available system because it has only one arm. Herein, we aimed to develop a new transurethral surgical system to facilitate two-arm ERBT and to report the results of preclinical experiments using tumor phantoms.Initially, we aimed to develop a brand-new surgical system for ERBT but, after trial and error, we re-directed our development to the creation of three elements: the left arm to grasp the tumor; the right arm to cut the tumor; and the system to operate the arms that can be attached to the existing surgical system (UES-40 SurgMaster® [Olympus Co. Ltd., Tokyo, Japan]). The current system was evaluated by performing simulated ERBTs using tumor phantoms made from konjac jelly.Following the assembly of developed arms into the UES-40 SurgMaster®, we conducted preliminary ERBTs. After performing several resections, we adopted a basket-shaped forceps as the left arm instead of grasping forceps and an arched electrode as the right arm. The two arms and single endoscope were placed in an equilateral triangle. We successfully performed ERBT for the tumor phantoms that ranged from 0.5 to 2.0 cm without major redo.Herein, we introduced our development for two-arm ERBT. The current concept of "two-hand transurethral surgery" has the potential to be developed in future in vivo and clinical trials.