Endoscopic Mucosal Resection with Circumferential Incision in Difficult Colorectal Lesions

A 76-year-old man with a medical history of hypertension and atrial fibrillation under apixaban was submitted to anterior resection for rectal adenocarcinoma following neoadjuvant radiochemotherapy. At the fifth year of postoperative endoscopic surveillance, an 18mm flat lesion (Paris type 0-IIb, nongranular laterally spreading lesion [LST-NG] and Kudo pit pattern type IIIs/IV) was found at the proximal transverse colon. A conventional endoscopic mucosal resection (EMR) attempt was ineffective due to nonlifting of the central portion of the lesion; biopsies were taken and the site was tattooed (SPOT®GI Supply, Camp Hill, PA, USA). Pathology showed a low-grade dysplasia adenoma and the patient was referred to our institution. Colonoscopy showed the 18-mm flat lesion in an area of tattooed mucosa (Fig. 1a). Initially, inject-and-cut EMR and a modified aspirative EMR using a rim-free cap were tried without success. Therefore, it was decided to perform a hybrid endoscopic submucosal dissection (ESD). First, an injection of submucosa using epinephrine-saline mixture (1: 100,000) and methylene blue was performed with difficulty in elevating the central portion of the lesion; then, submucosal access and circumferential incision were made using a ClearCut-knife 2 mm I-type (Finemedix Co. Ltd, Daegu, Republic of Korea); and, finally, an en-bloc resection using an oval 15-mm diathermic snare (Olympus, Spain) was performed without complications (Fig. 1b–d). Pathology of resection specimen (Fig. 2) showed a tubular adenoma with low-grade dysplasia (R0 resection) (Fig. 3a, b). Periprocedural management included stopping anticoagulation in the