Transurethral resection of the bladder tumor (TURBT) is not only the main method for staging of bladder cancer, but also the standard of surgical treatment for patients with non-muscle-invasive tumosr. Previously, the generally accepted technique for performing TURBT was electroresection using loop, but the active introduction of laser technologies has made the resection of the entire tumor in a single block (en bloc) widely available. According to some authors, en bloc resection of the bladder tumor allows to overcome some limitations of standard TURBT, including insufficient quality of the specimen containing the muscle layer and implantation of floating tumor cells in the bladder. However, the en bloc resection also has limitations. When using the en bloc resection for tumors larger than 3 cm, successful evacuation of the entire lesion becomes unlikely, therefore, it is usually recommended to use it for smaller tumors.
Publications devoted to the successful en bloc resection for large bladder tumors are included in the literature review. According to most authors, all the advantages of en bloc resection are preserved regardless of the tumor size, such as potentially better local control, lower recurrence rates outside the resection area, and higher quality of specimens for pathological study. A significant limitation of the technique is the inability to evacuate the tumor through the endoscope channel, which requires additional interventions (morcellation, dissection, ablation) or equipment (endoscopic baskets, forceps, etc.). Taking into account the conclusions of the Delphi consensus held in 2020, tumor size should not limit the use of the en bloc resection of the bladder tumor in the routine practice. However, an effective method for evacuating large bladder tumors that suits all specialists has not yet been proposed.

Keywords: large tumors, en bloc, endoscopic treatment, bladder cancer