Yoshinori Miyata

Endoscopic submucosal dissection of early esophageal cancer.

In Japan, the majority of esophageal cancers are squamous cell carcinomas. Because no lymph node metastasis was reported in squamous cell carcinomas limited to the intraepithelial layer (m1) or proper mucosal layer (m2), the Japanese Esophageal Association recommended endoscopic mucosal resection (EMR) as the treatment of choice for these cancers. However, these lesions often spread laterally, exceeding the limits of en bloc resectability with conventional EMR methods such as the EMR cap method. The lesions resected in piece-meal manner with conventional EMR methods are prone to recur locally. Therefore, we developed a method of mucosal resection with a hook-knife that enables endoscopic submucosal dissection safely and achieves a high rate of en bloc resection for larger lesions. The median size of the resected specimen and cancer by our method was 32 mm (range, 8-76 mm) and 28 mm (range, 4-64 mm), respectively. The en bloc resection rate was 95% (95 of 102) and the local recurrence rate was 0% (0 of 102). This procedure was safe, with only 6 cases (6%) of mediastinal emphysema, which improved with conservative treatment. Endoscopic submucosal dissection with the hook knife is a method of endoluminal surgery enabling large en bloc resections without increased surgical risks.

LEARNING CURVE FOR ENDOSCOPIC SUBMUCOSAL DISSECTION OF LARGE COLORECTAL TUMORS

Background and Aim:u2002 No studies have previously described the learning curve for colonic endoscopic submucosal dissection (ESD). The aim of the present study was to describe the learning curve for ESD of large colorectal tumors based on a single colonoscopists experience.

HEMOSTASIS WITH HOOK KNIFE DURING ENDOSCOPIC SUBMUCOSAL DISSECTION

Major complications reported with endoscopic submucosal dissection are bleeding and perforation. The most important step in preventing such complications is to maintain visualization of the submucosal layer. The hook knife is not only a useful cutting device for submucosal dissection, but the device also provides effective means for hemostasis and prevention of bleeding during endoscopic submucosal dissection. Vessels with a diameter of 1u2003mm or less do not bleed if cut with a hook knife using spray mode coagulation.

Criteria for Non-Surgical Treatment of Perforation during Colorectal Endoscopic Submucosal Dissection

Background and Aim: Endoscopic submucosal dissection (ESD) has recently been applied in the treatment of large colorectal tumors. However, indications for emergent surgery and criteria for conservative treatment of perforation remain unclear. The aim of this study was to clarify the criteria for non-surgical treatment of perforation during colorectal ESD. Methods: 219 colorectal tumors in 215 patients (136 men and 79 women; median age 69 years) were removed by performing ESD. The procedural outcomes, complications, prognoses, and criteria for non-surgical treatment of perforation were retrospectively analyzed by using our prospectively corrected database. Results: The en-bloc and complete en-bloc resection rates were 92.7% (203/219) and 85.8% (188/219), respectively. The rate of discontinued ESD was 2.3% (5/219). The immediate and delayed perforation rates were 5.0% (11/219) and 0%, respectively. One of these patients required emergent surgery because of a residual lesion and localized peritonitis caused by an unsuccessful closure. The other 10 patients recovered with conservative treatment after successful closure with hemoclips and complete resection. The defects in all patients were successfully closed by using hemoclips. None of the patients had signs of diffuse peritonitis. The other factors, i.e. absence of localized peritonitis, high-grade fever, and acceleration of inflammatory reaction, were not associated with the success or the failure of the non-surgical treatment. Conclusions: The criteria for non-surgical treatment of perforation caused by colonic ESD were absence of diffuse peritonitis and successful closure.

MECKEL’S DIVERTICULUM WITH ULCERATION DIAGNOSED BY DOUBLE BALLOON ENTEROSCOPY

A 31‐year‐old man was referred to our hospital for an evaluation of recurrent episodes of melena. Esophagogastroduodenoscopy, total colonoscopy, computed tomography and Tc‐99u2003m scintigraphy were performed at a previous hospital, but the bleeding source remained unidentified. Double balloon enteroscopy (DBE) was performed with the use of an anal approach at our hospital. DBE was inserted into the ileum approximately 100u2003cm from the ileocecal valve, and then Meckel’s diverticulum was discovered. There was a circular ulceration in the middle part of the diverticulum without adherent blood clots, visible vessels nor heterotopic gastric mucosa. Meckel’s diverticulum was identified as the bleeding source, but an immediate risk of rebleeding was considered relatively low. The patient chose conservative therapy without surgery. Two years later, he is well, without further bleeding episodes. DBE made it possible not only to diagnose the existence of the Meckel’s diverticulum but also to assess the risk of rebleeding.

Superficial esophageal cancer type 0-IIa+IIc (m2): a case atlas

Conventional esophagoscopy revealed a slightly elevated lesion with a shallow depressed part (0-IIa+IIc), 20 mm in size, on the left wall of the middle thoracic esophagus (Figs. 1, 2). The border of the lesion was indistinct by conventional esophagoscopy. The surface of the elevated lesion was slightly rough, and its color was red. A shallow depressed part was seen at the oral and anal sides of the elevated lesion. The lesion was stained weakly by toluidine blue, and no strongly stained part was seen (Figs. 3, 4). The lesion revealed clearly an unstained area after iodine staining (Fig. 5). Magnifying endoscopy revealed irregular micovessels in the anal part of the lesion. The irregularity of the oral part was not so severe (Fig. 6). However, an area devoid of capillaries surrounded by abnormal vessels was observed at the elevated and anal part of the lesion. However, the caliber of the irregular vessels was not so wide (Figs. 8, 9). Therefore, we diagnosed the carcinoma had invaded the proper mucosal layer (m2) and had not invaded the muscularis mucosa. Endoscopic submucosal dissection (ESD) with the hook knife was carried out, and en bloc resection of the lesion was performed. Macroscopic fi ndings