USEFULNESS OF SODIUM ALGINATE FOR INJECTION SOLUTION IN COLORECTAL ENDOSCOPIC SUBMUCOSAL DISSECTION

Aims Colorectal endoscopic submucosal dissection (ESD) is technically difficult especially when the submucosal layer cannot be sufficiently lifted even after submucosal injection. Therefore, the choice of injection solution is very important, and hyaluronic acid has been considered as the best injection solution for colorectal ESD. However, hyaluronic acid is expensive, and some lesions cannot be sufficiently lifted or kept lifted for a long time even after its use. On the other hand, sodium alginate (Liftal K, Kaigen Pharma Co., Osaka) is a novel injection solution extracted from seaweeds, and has high viscosity. Sodium alginate is also used as medicines for protection of gastric mucosa or hemostasis, and costs lower than hyaluronic acid. It has recently been reported it is useful for gastric ESD and esophageal ESD, but its usefulness for colorectal ESD is not elucidated. We therefore investigated the efficacy of sodium alginate for colorectal ESD.

Methods Colorectal ESD for nineteen lesions of sixteen patients was performed with sodium alginate as injection solution at our hospital from September 2019 and November 2019. Seventeen lesions of fourteen patients were enrolled, and two lesions which revealed the muscle retracting sign suggesting deep submucosal invasion were excluded in this study. Treatment outcome were retrospectively analyzed.

Results All lesions were resected with ESD in en bloc manner without any traction systems, and without any complications. Average tumor diameter, resected diameter, and procedure time were 30.8 mm, 37.5 mm, and 28.6 minutes, respectively. High elevation by submucosal injection with sodium alginate was obtained and it showed long-acting in all cases, which enabled speedy dissection.

Conclusions Sodium alginate seems to be safe and a very good option for the injection solution of colorectal ESD.