Animal Experimental Study on Magnetic Anchor Technique-assisted Endoscopic Submucosal Dissection of Early Gastric Cancer

Background: Gastric cancer (GC) has high morbidity and mortality. Moreover, because GC has no typical symptoms in the early stages, most cases are already in the advanced stages by the time the symptoms appear, thus resulting in poor prognosis and a low survival rate. Endoscopic submucosal dissection (ESD) can realize the early detection and diagnosis of GC and become the main surgical method for early GC. However, ESD has a steep learning curve and high technical skill requirements for endoscopists, which is not conducive to its widespread implementation and advancement. Therefore, a series of auxiliary techniques have been derived.

Aim: To evaluate the safety and efficacy of magnetic anchor technique (MAT)-assisted ESD in early GC.

Methods: This was an animal experiment. The experimental models were the isolated stomachs of pigs, which were divided into two groups, namely the study group ( = 6) with MAT-assisted ESD and the control group ( = 6) with traditional ESD. Comparing the total surgical time, incidence of surgical complications, complete mucosal resection rate, specimen size, and the scores of endoscopist's satisfaction with the procedure reflected their feelings about convenience during the surgical procedure between the two groups. The magnetic anchor device for auxiliary ESD in the study group comprised three parts, an anchor magnet (AM), a target magnet (TM), and a soft tissue clip. Under gastroscopic guidance, the soft tissue clip and the TM were delivered to the pre-marked mucosal lesion through the gastroscopic operating hole. The soft tissue clip and the TM were connected by a thin wire through the TM tail structure. The soft tissue clip was released by manipulating the operating handle of the soft tissue clip in a way that the soft tissue clip and the TM were fixed to the lesion mucosa. , ESD is aided by maneuvering the AM such that the mucosal dissection surface is exposed.

Results: The total surgical time was shorter in the study group than in the control group (26.57 ± 0.19 29.97 ± 0.28, < 0.001), and the scores of endoscopist's satisfaction with the procedure were higher in the study group than in the control group (9.53 ± 0.10 8.00 ± 0.22, 0.001). During the operation in the study group, there was no detachment of the soft tissue clip and TM and no mucosal tearing. The magnetic force between the AM and TM provided good mucosal exposure and sufficient tissue tension for ESD. The mucosal lesion was completely peeled off, and the operation was successful. There were no significant differences in the incidence of surgical complications (100% 83.3%), complete mucosal resection rate (100% 66.7%, = 0.439), and specimen size (2.44 ± 0.04 cm 2.49 ± 0.02, = 0.328) between the two groups.

Conclusion: MAT-ESD is safe and effective for early GC. It provides a preliminary basis for subsequent internal animal experiments and clinical research.