Motomi Terasaki

Clinical outcomes of endoscopic submucosal dissection and endoscopic mucosal resection for laterally spreading tumors larger than 20 mm.

Background and Aims:  Colorectal laterally spreading tumors (LST) > 20 mm are usually treated by endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR). Endoscopic piecemeal mucosal resection (EPMR) is sometimes required. The aim of our study was to compare the outcomes of ESD and EMR, including EPMR, for such LST.

Management of T1 colorectal carcinoma with special reference to criteria for curative endoscopic resection

Background and Aim:  In guidelines 2010 for the treatment of colorectal cancer from the Japanese Society for Cancer of the Colon and Rectum (JSCCR), the criteria for identifying curable T1 colorectal carcinoma after endoscopic resection were well/moderately differentiated or papillary histologic grade, no vascular invasion, submucosal invasion depth less than 1000 µm and budding grade 1 (low grade). We aimed to expand these criteria.

CURRENT STATUS AND FUTURE PERSPECTIVES OF ENDOSCOPIC SUBMUCOSAL DISSECTION FOR COLORECTAL TUMORS

Endoscopic submucosal dissection (ESD) allows for en bloc tumor resection irrespective of the size of the lesion. In Japan, ESD has been established as a standard method for endoscopic ablation of malignant tumors in the upper gastrointestinal tract. Although the use of colorectal ESD has been gradually spreading with the development of numerous devices, ESD has not yet been fully established as a standard therapeutic method for colorectal lesions. Currently, colorectal ESD is performed as an ‘advanced medical treatment’ without national health insurance coverage. With the recent accumulation of numerous cases, the safety and simplicity of colorectal ESD have improved remarkably. Currently in Japan, a prospective multicenter cohort study organized by the Japan Gastroenterological Endoscopy Society is ongoing to clarify the safety and efficacy of colorectal ESD to obtain remuneration from national health insurance. In this report, we showed the outcome regarding safety and efficacy of colorectal ESD through a review of the published work. Of 2719 cases with colorectal ESD at 13 institutions, the complete en bloc resection and perforation rates were 82.8% (61–98.2%, 2082/2516) and 4.7% (1.4–8.2%, 127/2719), respectively. Additional surgery for perforation was very rare because perforations were tiny enough to be closed endoscopically by clips in most of the cases and treated conservatively. In the near future, colorectal ESD will be a common therapeutic method for early colorectal carcinoma.

Warning for unprincipled colorectal endoscopic submucosal dissection: Accurate diagnosis and reasonable treatment strategy

Piecemeal endoscopic mucosal resection (EMR) is generally indicated for laterally spreading tumors (LST) >2 cm in diameter. However, the segmentation of adenomatous parts does not affect the histopathological diagnosis and completeness of cure. Thus, possible indications for piecemeal EMR are both adenomatous homogenous‐type granular‐type LST (LST‐G) and LST‐G as carcinoma in adenoma without segmentalizing the carcinomatous part. Diagnosis of the pit pattern using magnifying endoscopy is essential for determining the correct treatment and setting segmentation borders. In contrast, endoscopic submucosal dissection (ESD) is indicated for lesions requiring endoscopic en bloc excision, as it is difficult to use the snare technique for en bloc excisions such as in non‐granular‐type LST (LST‐NG), especially for the pseudodepressed type, tumors with a type VI pit pattern, shallow invasive submucosal carcinoma, largedepressed tumors and large elevated lesions, which are often malignant (e.g. nodular mixed‐type LST‐G). Other lesions, such as intramucosal tumor accompanied by submucosal fibrosis, induced by biopsy or peristalsis of the lesion; sporadic localized tumors that occur due to chronic inflammation, including ulcerative colitis; and local residual early carcinoma after endoscopic treatment, are also indications for ESD. In clinical practice, an efficient endoscopic treatment with segregation of ESD from piecemeal EMR should be carried out after a comprehensive evaluation of the completeness of cure, safety, clinical simplicity, and cost–benefit, based on an accurate preoperative diagnosis.

Clinical outcomes of endoscopic submucosal dissection for rectal tumor close to the dentate line

p r s f s L J m Endoscopic mucosal resection is a standard therapy for colorectal tumors. Although endoscopic submucosal dissection (ESD) is not a standard therapy, it has emerged as a feasible treatment option because of improved techniques and specialized devices.4-8 Lesions close to the dentate line can be difficult to remove endoscopically because of the risk of bleeding from the rectal venous plexus. In addition, sensory nerves in the squamous epithelium below the dentate line make pain likely during the procedure. Moreover, the proximity of the anal sphincter makes maintaining a good visual field difficult. Therefore, special approaches are necessary for treating lesions in this area. Generally, ESD proceeds by handling the submucosal blood vessels. The en bloc resection rate for large colorectal tumors is high. As such, ESD is a logical choice for lesions close to the dentate line. Recently, Sanchez-Yague et al9 reported the successful use of ESD for resecting a ectal polyp proximal to the dentate line by using local idocaine injection. However, no reports, to our knowldge, have summarized the clinical results of ESD for esions close to the dentate line among many patients. ere, we report our experience with ESD and clinical utcomes in patients after ESD for lesions close to the entate line.