Usefulness of a novel electrosurgical knife, the insulation-tipped diathermic knife-2, for endoscopic submucosal dissection of early gastric cancer

Abstract

Background: Although endoscopic submucosal dissection (ESD) of early gastric cancer using an insulation-tipped diathermic (IT) knife enables the removal of large and ulcerative lesions en bloc, expert endoscopic skill is required. We developed an improved IT knife (IT-2) and compared its efficacy and safety with that of the original IT knife (IT-OM).

Methods: We performed ESD of 602 gastric cancers. Of these, 314 previously untreated single lesions of initial onset were analyzed. Operating time, rate of en-bloc resection, and incidence of complications were compared in the IT-2 group (161 patients) and IT-OM group (153 patients). Lesions were further analyzed as to whether they met the Japanese Gastric Cancer Association indications for ESD or extended indications.

Results: Mean resection time was significantly shorter in the IT-2 than in the IT-OM group (48 vs 63 min). There were fewer surgeries lasting longer than 2 h in the IT-2 group than in the IT-OM group (3% vs 12%). En-bloc and margin-free resection rates in the IT-OM and IT-2 groups were 95% and 99%, respectively. Perforations occurred in 3.9% of patients in the IT-OM group and in 5% of patients in the IT-2 group (difference not significant [NS]). The incidence of postoperative hemorrhage was 7.8% in the IT-OM group and 8.7% in the IT-2 group (NS). In both groups, complications were treated endoscopically, and emergency surgery was unnecessary.

Conclusion: Resectability and complication rates were similar in the two groups. However, operating time was shorter with IT-2, irrespective of the indications for the performance of ESD. This study suggests benefits of the IT-2 over the IT-OM.