Endoscopic submucosal dissection (ESD) using the needle knife: its superiority to ESD using the insulation-tipped diathermic knife in physicians intending to master ESD.

In the absence of a supervisor, we conducted endoscopic submucosal dissection (ESD) procedures using the needle-knife and insulation-tipped (IT) diathermic knives for 516 gastric neoplasms in 443 Japanese patients with the diseases. No significant difference was found between IT knife ESD and needle-knife ESD in en bloc resection rates with tumor-free margins (89.8% and 92.9% for IT knife ESD and needle-knife ESD, respectively) and perforation rates (2.2% and 4.6%, respectively). However, the mean procedure time was significantly (P<0.05) shorter in IT knife ESD than in needle-knife ESD (74 and 88 min, respectively) and reached a plateau after accumulating 120 cases of ESD in both procedures. We required a less number of ESD cases before being proficient at needle-knife ESD than in IT knife ESD (30 cases and 60 cases, respectively). Needle-knife ESD is recommended for physicians who intend to master ESD hereafter.