Post written by Tomoaki Tashima, MD, PhD, from the Department of Gastroenterology, Saitama Medical University International Medical Center, Saitama, Japan.

A 78-year-old man was referred to our institute for treatment of a flat elevated (20-mm diameter) lesion observed around and within the diverticulum near the ileocecal valve of the ascending colon. The lesion border was marked via an electrosurgical snare tip. Underwater EMR was attempted initially.

However, the injected water mixed with luminal residue; a clear visual field could not be obtained easily. Subsequently, carbon dioxide insufflation was discontinued, and we injected gel (VISCOCLEAR; Otsuka Pharmaceutical Factory, Tokushima, Japan), filling the perilesional lumen. Gel immersion endoscopy secured a clear lesion margin view; the lesion was resected with a snare.

Most of the gel was suctioned, and we reinserted an endoscope with a 12/6t over-the-scope clip (OTSC). The residual lesion inside the diverticulum was sufficiently suctioned into the applicator cap, and the OTSC was successfully deployed perilesionally. The lesion inside the diverticulum protruded into the lumen, and it was resected above the OTSC using a snare without adverse events.

Endoscopically, no tumor residues were evident. The procedure time was 15 minutes. The patient was hospitalized after the procedure, and antibiotics were administered for 2 days postoperatively. On postoperative day 2, oral intake was resumed. He did not develop somatic symptoms or adverse events and was discharged on postoperative day 3.

Pathologically, the tumor was diagnosed as an intramucosal adenocarcinoma in high-grade adenoma without lymphovascular invasion. The horizontal and vertical margins were inconclusive and negative, respectively. On follow-up endoscopic examination, the mucosal defect had a residual OTSC and scarred entirely within 2 months, without residual tumor.

We achieved endoscopic resection of a lesion that had considerably extended into the colonic diverticulum using 2 endoscopic resection techniques, thus avoiding surgical resection. In situations where the lesion has extended into the colonic diverticulum, and a full-thickness resection device is unavailable, the treatment strategies used in this case may be acceptable.

The gel is colorless and transparent; it does not rapidly mix with luminal residue, blood, or clots. Therefore, it has been reported to be useful for securing clearer endoscopic visualization during endoscopic procedures and hemostasis than in underwater conditions.

With these collaborative techniques, no local submucosal injection was performed. Because local injection causes edema of the diverticulum, deploying the OTSC to include the entire diverticulum is impossible. This is why we chose gel immersion EMR.

Furthermore, the gel provided a clearer view of the lesion margin than in underwater conditions, and the buoyancy of the lesion under gel immersion was used for accurate snaring.

Regarding endoscopic resection using an OTSC, to obtain a secure lateral margin inside the diverticulum, the entire diverticulum should be sufficiently suctioned into the applicator cap of the OTSC, and the OTSC should be deployed in that state. Based on our experience with endoscopic resection using an OTSC, we were aware that target lesions ≤10 mm could be sufficiently suctioned into the applicator cap of the OTSC.

Endoscopic views. A, 20-mm flat elevated lesion around and into the diverticulum near the ileocecal valve of the ascending colon. The size of the diverticulum was approximately 10 mm. B, The lesion extended considerably into the diverticulum, almost covering the orifice.

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.