Learning curve for endoscopic submucosal dissection of early colorectal neoplasms with a monopolar scissor-type knife: use of the cumulative sum method

Abstract

Objective: Although scissor-type knives such as the Stag-Beetle (SB) Knife Jr are expected to result in a safe and easy colorectal endoscopic submucosal dissection (CR-ESD), information regarding the learning curve is lacking. Therefore, this study evaluated the learning curve with using SB Knife Jr. Materials and methods: We retrospectively reviewed 507 CR-ESD procedures performed in 464 patients using SB Knife Jr. The primary endpoint was a learning curve to achieve a satisfactory complete resection rate. The secondary endpoints were learning curves to achieve a satisfactory en bloc resection rate, curative resection rate, and resection speed. Results: The complete, en bloc, and curative resection rates were 91.9%, 95.9%, and 84.0%, respectively. Moving average analysis showed that 39 cases were required for a complete resection rate of >80%, 41 for an en bloc resection rate of >90%, and 50 for a curative resection rate of >75%. We divided the procedure into three phases using the cumulative sum method: I, II, and III (cases 1-36, 37-119, and 120-507, respectively). Although we found no significant between-phase differences, the complete resection rate showed an increasing trend in Phase III (83.3 vs. 89.2 vs. 93.3%; p ¼ .099). The en bloc resection rate (91.7 vs. 91.6 vs. 97.2%; p ¼ .047) and resection speed (20.5 vs. 7.2 vs. 6.8 min/ cm 2 ; p < .001) were greater in Phase III. Despite the larger specimen size (27.3 vs. 38.2 vs. 40.4 mm; p < .001) and more severe fibrosis (p < .001) in Phase III, the procedure time was shorter (73.8 vs. 57.8 vs. 54.2 min; p ¼ .041). The curative resection rate was not significantly different between phases. Conclusions: SB Knife Jr enables safe and easy CR-ESD during the introductory period compared to the conventional tip-type knife and has an acceptable learning curve. Therefore, using this knife will encourage the widespread adoption of CR-ESD in Asian general hospitals and non-Asian countries.

Endoscopic submucosal dissection vs endoscopic mucosal resection for colorectal polyps: A meta-analysis and meta-regression with single arm analysis

“…The potential of ESD resection is limited by the difficulty in conducting the procedure as the length of procedure for ESD even when performed by experienced endoscopists can be three times longer than that for EMR[ 43 ]. However, the advancement in endoscopic resection equipment has been shown to shorten the procedure time despite a relatively short training duration[ 44 ]. Using the cumulative sum method, Miyakawa et al [ 44 ] recently reported the use of Stag-Beetle Knife Jr for ESD in a Japan single-center study generated good learning curve to achieve satisfactory resection speed (min/cm 2 ), which allowed the acquisition of proficient and safe skills within 120 cases[ 44 ].…”

“…However, the advancement in endoscopic resection equipment has been shown to shorten the procedure time despite a relatively short training duration[ 44 ]. Using the cumulative sum method, Miyakawa et al [ 44 ] recently reported the use of Stag-Beetle Knife Jr for ESD in a Japan single-center study generated good learning curve to achieve satisfactory resection speed (min/cm 2 ), which allowed the acquisition of proficient and safe skills within 120 cases[ 44 ]. Other alternatives to ESD do exist, such as hybrid ESD and pre-cut EMR.…”

The efficacy of prophylactic clip closure of mucosal defects after colorectal endoscopic submucosal dissection on delayed bleeding

“…Although the previous reports suggested that tumor size, location, and use of antiplatelet agents are the risk factors of delayed bleeding, these were not relevant [37][38][39][40]. This study validated CR-ESD using scissor-type knives such as SB Knife Jr. SB Knife Jr also has a function as hemostatic forceps and enables hemostasis or precoagulation without device replacement and may lead to low delayed bleeding rate as compared with the conventional needle-type knife [41,42]. These facts might be the reason for the small number of delayed bleeding cases, which did not result in significant differences in risk factors.…”

Endoscopic Submucosal Dissection vs Endoscopic Mucosal Resection for Colorectal Polyps. A Meta-Analysis&nbsp;

“…44 However, the advancement in endoscopic resection equipment has been shown to shorten the procedure time despite a relatively short training duration. 45 Using the cumulative sum (CUSUM) method, Miyakawa et al recently reported the use of Stag-Beetle Knife Jr for ESD in a Japan single-center study generated good learning curve to achieve satisfactory resection speed (min/cm 2 ), which allowed the acquisition of pro cient and safe skills within 120 cases. 45 Other alternatives to ESD do exist, such as hybrid ESD and pre-cut EMR.…”

“…45 Using the cumulative sum (CUSUM) method, Miyakawa et al recently reported the use of Stag-Beetle Knife Jr for ESD in a Japan single-center study generated good learning curve to achieve satisfactory resection speed (min/cm 2 ), which allowed the acquisition of pro cient and safe skills within 120 cases. 45 Other alternatives to ESD do exist, such as hybrid ESD and pre-cut EMR. This hybrid approach has been shown to have lower en bloc resection rate (68.4% vs 91.0%) and complete resection rate (60.6% vs 82.9%) than conventional ESD.…”