Balloon overtube can improve maneuverability of the endoscope during colorectal endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is a minimally invasive therapy that enables en bloc resection for early colorectal neoplasms. However, it is considered to still be challenging because of poor maneuverability of the endoscope, especially for lesions located at the proximal colon.1, 2 In such locations, we sometimes experience ‘paradoxical movement’, whereby the tip of the endoscope retracts even when the endoscope is advanced outside the patient. To achieve a safe and successful procedure, we need to overcome such problematic conditions. Previously, we described that a balloon overtube can improve accessibility to the lesion and facilitate scope manipulation for colorectal ESD.3 Herein, we present a case of cecal ESD with good application for balloon overtube assistance (ST-SB1; Olympus, Tokyo, Japan) (Fig. 1). A severely obese woman (body mass index 42) was introduced to NTT Medical Center Tokyo because of difficulty of total colorectal examination. First, we carried out colonoscopy under fluoroscopy to confirm the scope shape and to prevent the scope looping and sagging. However, we also could not reach the cecum. As her abdominal cavity space was huge, axial force exerted by the endoscopist was not translated to forward motion of the tip of the colonoscope, which resulted in the cause of paradoxical movement (Fig. 2a). Therefore, we attempted to use a balloon overtube. As shown in Figure 2b, the endoscope can be kept straight and maneuverability of the endoscope was much improved. After identification of a cecal laterally spreading tumor (LST), 30 mm in diameter, we conducted ESD and removed the lesion en bloc without any complications. As the resected lesion was pathologically diagnosed as well-differentiated intramucosal adenocarcinoma, additional surgical resection was not carried out. Selecting a target lesion located in the proximal colon with poor operability of the endoscope, a balloon overtube can dramatically change such a situation. We propose that the ESD operator should confirm application of a balloon overtube during preoperative endoscopic examination. AUTHORS DECLARE NO conflicts of interest for this article.