Post written by Robert Bechara, MD, from Queen’s University, Kingston Health Sciences Center, Kingston, Ontario, Canada.

This video demonstrates the use of a thulium laser system for colorectal endoscopic submucosal dissection (ESD) in a 68-year-old man with a 3.5-cm rectal lesion detected following a positive fecal immunochemical test result. The lesion was classified as Paris Is and Japan Narrow-Band Imaging Expert Team 2B and considered appropriate for en bloc resection.

After submucosal injection, circumferential incision and submucosal dissection were performed using a thulium laser fiber (SOLTIVE SuperPulsed; Olympus, Tokyo, Japan). An underwater technique was used to minimize tissue carbonization and optimize visualization. The laser was set to approximately 0.1 J per pulse at 80 Hz (8 W), allowing precise cutting with simultaneous coagulation. The procedure was completed in 75 minutes without the need for hemostatic forceps, and no intraoperative or delayed adverse events occurred. Final histopathology revealed a tubulovillous adenoma with high-grade dysplasia and clear (R0) margins.

Although thulium laser technology is well established in endourologic procedures, its application in GI endoscopy remains limited. This case highlights the technical feasibility of thulium laser–assisted colorectal ESD and presents its potential advantages over conventional electrosurgical knives, including very shallow penetration depth, high cutting precision, and effective coagulation.

This case illustrates that thulium laser–assisted ESD can achieve efficient en bloc resection with reliable hemostasis and without the need for adjunctive coagulation devices. Several practical points are highlighted. First, the use of an underwater field during laser ESD is critical to reducing tissue carbonization and maintaining a clear endoscopic view. Second, endoscopists may appreciate the laser’s precise tissue effect and strong coagulative properties, as well as its potential to limit collateral thermal injury because of its shallow penetration depth.

This case supports the technical feasibility and short-term safety of thulium laser–assisted colorectal ESD, but further prospective studies should guide broader adoption. Larger clinical series will be required to better define comparative efficacy, safety, and learning-curve considerations relative to conventional ESD devices.

In summary, this case shows the feasibility and potential advantages of thulium laser–assisted colorectal ESD. Our experience builds on prior work: Cho et al¹ first introduced thulium laser use for gastric ESD over a decade ago, to our knowledge, and Tontini et al² subsequently showcased its efficacy in ex vivo colorectal models. Extending these observations, our video suggests that the thulium laser’s precise cutting, shallow penetration, and effective coagulation make it a promising alternative to conventional electrosurgical knives.

Nevertheless, larger prospective studies are needed to confirm its safety, efficacy, and long-term outcomes before widespread adoption. We hope this case will stimulate further interest and research into thulium laser applications in GI endoscopy.

Thulium laser system. A, The energy source. B, Laser fiber.

Read the full article online.

The information presented in Endoscopedia reflects the opinions of the authors and does not represent the position of the American Society for Gastrointestinal Endoscopy (ASGE). ASGE expressly disclaims any warranties or guarantees, expressed or implied, and is not liable for damages of any kind in connection with the material, information, or procedures set forth.

1. Cho J-H, Cho JY, Kim M-Y, et al. Endoscopic submucosal dissection using a thulium laser: preliminary results of a new method for treatment of gastric epithelial neoplasia. Endoscopy 2013;45:725-8. ↩︎
2. Tontini GE, Neumann H, Pastorelli L, et al. Thulium laser in interventional endoscopy: animal and human studies. Endoscopy 2017;49:365-70. ↩︎