Endoscopic submucosal dissection with a novel cap-assisted additional working channel (AWC duo) increases resection speed: a pilot study

Objective The additional working channel duo (AWC duo) is a novel ‘bi-manual’ tool to perform endoscopic submucosal dissection (ESD) combining an AWC with a transparent spacer cap to facilitate ESD procedures. In this study, we investigate the resection speed, safety and feasibility of AWC duo ex vivo and in patients. Methods and design In an ex vivo porcine stomach model, n=15 resections on 4 cm lesions were performed using the AWC duo ESD or conventional cap-assisted ESD. Resection time, en-bloc rate and feasibility were analysed. Data of n=22 patients that had undergone AWC duo assisted ESDs were retrospectively evaluated. Result Ex vivo, dissection time was significantly shorter in the AWC duo group compared with standard cap-assisted ESD (17 min vs 21 min, p<0.05). The extra channel was used for 34% (range: 25–60%) of the resection time. The AWC duo was rated as helpful in 60%, very helpful in 27% and not helpful in 13% of resections ex vivo. 22 patients were analysed retrospectively. Average size of the lesions was 44.5 mm (range: 25–80 mm). Localisations were oesophagus 2, stomach 1, colon 15 and rectum 4. R0 resection was achieved in 21/22 (95%) of cases and no perforations or significant bleedings occurred. In patients, the AWC duo was used for an average of 37% of the dissection time and was rated as useful in 8/22 cases (36%) and very useful in 14/22 (64%) cases. Conclusion AWC duo reveals a significant reduction of dissection time compared with standard cap-assisted ESD in the porcine ex vivo model. First patient data highlight the safety and practicability of AWC duo as a novel and promising tool to facilitate ESD resections in the upper and lower gastrointestinal tract.