Retrospective study of technical aspects and complications of endoscopic submucosal dissection for large superficial colorectal tumors.

BACKGROUND AND AIM: Colorectal endoscopic submucosal dissection (ESD) is widely carried out, but is still considered difficult. In 2010, a tumor size of ≥ 50 mm and less experience in colorectal ESD were reported as independent risk factors for complications such as perforation, delayed perforation and postoperative bleeding. In order to overcome such difficulties, we developed a scissors-type grasping device and reported the treatment results of a multicenter study. The aim of the present study was to investigate therapeutic outcomes of colorectal ESD of different tumor sizes. METHODS: Group A (134 tumors): tumor size < 50 mm, and Group B (16 tumors): tumors ≥ 50 mm. All tumors were removed by ESD. We retrospectively evaluated the clinicopathological features of the tumors and the treatment results. RESULTS: Age, sex, tumor location and histopathological diagnosis were not different between the two groups. Laterally spreading tumor non-granular type was more often observed in Group A (64/134, 47.8%) than in Group B (0/16, 0%). Procedure time was significantly longer in Group B (Group A: 38 min; Group B: 86 min, P < 0.01). However, procedure speed was significantly faster in Group B (Group A: 0.21 cm(2) /min; Group B: 0.37 cm(2) /min, P < 0.01). No complications were observed in either group. The en bloc resection rate, en bloc R0 resection rate, and en bloc curative resection rate were similar between the groups with no significant differences. CONCLUSIONS: Procedure speed for Group B was faster than that for Group A. Group B was treated as safely as Group A.

Endoscopic mucosal resection with circumferential mucosal incision of duodenal carcinoid tumors.

Duodenal carcinoids are a rare form of neuroendocrine tumors, and tend to invade the submucosa during the early stage. Endoscopic treatment is generally recommended for duodenal carcinoids less than 10 mm in diameter. Although a few reports have described the use of endoscopic resection of duodenal carcinoids, there are no published studies on endoscopic mucosal resection with circumferential mucosal incision (EMR-CMI). We performed EMR-CMI for 5 cases of duodenal carcinoids in the duodenal bulb. The mean tumor diameter was 4.6 ± 1.8 mm. Although all of the tumors were located in the submucosa, R0 resection was performed without complication in each case. EMR-CMI may thus be a safe and effective treatment for duodenal carcinoids less than 10 mm in diameter.

Current status of colorectal endoscopic submucosal dissection in Japan and other Asian countries: progressing towards technical standardization.

AIM: The primary purpose of this questionnaire survey study was to determine the current status of colorectal endoscopic submucosal dissection (ESD) in specialized Japanese referral centers before and after introduction of a government-approved advanced medical treatment system; and, secondly, to determine the current status of colorectal ESD in other Asian specialized referral centers. METHODS: A total of 1321 colorectal ESDs were performed in 11 institutions including two Asian centers outside Japan. RESULTS: Overall en-bloc resection, curative resection, R0 resection, perforation, delayed bleeding and emergency surgery rates were 95.4%, 89.1%, 87.2%, 2.9%, 2.5% and 0.2%, respectively. Similar clinical results were reported in the two Asian centers. CONCLUSION: There were no significant differences with regards to clinical results between the two periods although the perforation rate decreased from 3.3% to 2.4%. In addition, colorectal ESD has become increasingly standardized technically at specialized referral centers not only in Japan, but several other Asian referral institutions as well.

Efficacy of novel SB knife Jr examined in a multicenter study on colorectal endoscopic submucosal dissection.

BACKGROUND AND AIM: Secure manipulation of forceps in endoscopic submucosal dissection (ESD) for colorectal tumors is sometimes hindered by the characteristics of that organ. SB knife Jr, which are scissor forceps using a mono-pole high frequency, were developed to avoid the difficulty of ESD operation in the colorectum. The aim of the present study was to examine the effectiveness of the SB knife Jr in colorectal ESD in 11 hospitals, mostly in northeastern Japan. MATERIALS: One hundred and two colorectal tumors (49 non-granular laterally spreading tumor [LST] lesions, 39 granular LST lesions and 14 other lesions) that were resected by ESD operations using SB knife Jr between October 2009 and March 2010. RESULTS: All tumors (102/102) were resected en bloc and could be observed in detail. The mean size of the resected pieces was 40.3 mm. The mean operation time was 54.2 min. Of the complications, one case of micro-perforation occurred during the manipulation of submucosal dissection, and this case was treated with clips in that operation. The rates of resection carried out only with SB knife Jr were 74.5% (76/102). CONCLUSION: The novel ESD using SB knife Jr in the colorectum offers a breakthrough in resection techniques for not only expert endoscopists but also general endoscopists.

Retrospective multicenter study concerning electrocautery forceps with soft coagulation for nonmalignant gastroduodenal ulcer bleeding in Japan.

Electrocautery forceps with soft coagulation are actively used for treatment of bleeding and nonbleeding visible vessels during endoscopic submucosal dissection, but the usefulness of gastroduodenal ulcer bleeding has not been elucidated so far. The purpose of this paper is to elucidate the outcomes of electrocautery forceps with soft coagulation for peptic and artificial gastroduodenal ulcer bleeding. A retrospective multicenter study of consecutive case series during one year involved nine departments of high-volume hospitals in Japan. The study included 128 consecutive patients (62 with peptic ulcers and 66 with artificial ulcers) with bleeding nonmalignant gastroduodenal ulcers that were revealed using emergency endoscopy between January 2008 and December 2008. Hemostasis was carried out using electrocautery forceps with soft coagulation. Rates of successful initial hemostasis, rebleeding, transfer to surgery, and death according to peptic and artificial ulcer bleeding were recorded. Successful initial endoscopic hemostasis was obtained in 61 peptic ulcer patients (98.4%) and 66 artificial ulcer patients (100%). Rebleeding was observed in seven peptic ulcer patients (11.5%) and five artificial ulcer patients (7.6%). Rates of successful management with endoscopic methods alone were 96.8% (60/62) and 100% (66/66) in peptic ulcer patients and artificial ulcer patients, respectively. There were no severe complications or deaths related to the management of gastroduodenal ulcer bleeding. The novel endoscopic method using electrocautery forceps with soft coagulation for gastroduodenal ulcer bleeding seems to provide safety and efficacy that is comparable with that of endoscopic hemostasis with other established hemostatic techniques.

Current managements and outcomes of peptic and artificial ulcer bleeding in Japan.

The recent trend of gastroduodenal ulcer bleeding in Japan has not been elucidated in detail and the data for a new categorized type, artificial ulcer bleeding, is completely lacking. The purpose of this paper is to elucidate current managements and outcomes of peptic and artificial ulcer bleeding in Japan. A retrospective multicenter study of consecutive case series was carried out during one year at nine departments of high-volume hospitals in Japan. The study included 325 consecutive patients (239 with peptic ulcers and 86 with artificial ulcers) with bleeding nonmalignant gastroduodenal ulcers that were revealed by emergency endoscopy between January 2008 and December 2008. Hemostasis was carried out mainly using endoscopic treatments. Rates of successful initial hemostasis, rebleeding, transfer to surgery, and death were recorded according to peptic and artificial ulcer bleeding. Additionally, preferred endoscopic methods, concomitant use of antisecretory drugs, and timing of second-look endoscopy were also measured. A total of 227 (99.1%) of 229 peptic ulcer patients with endoscopic treatment and all (100%) 84 artificial ulcer patients underwent successful tentative hemostasis. Rebleeding occurred in 23 peptic ulcer patients (10.1%) and 10 artificial ulcer patients (11.9%). One peptic ulcer patient and two artificial ulcer patients had final surgical rescue due to rebleeding. No death was observed. Monotherapy was predominant (around 65% of cases) in both types of ulcers. The coagulation forceps method was more frequently applied in artificial ulcers (P < 0.05). A per oral proton pump inhibitor was more frequently used in artificial ulcers (P < 0.05), although an intravenous proton pump inhibitor was used in the majority of patients in both types of ulcers. The frequency of second-look endoscopy in peptic ulcers (88%) was significantly higher than that in artificial ulcers (71%) (P < 0.05). There seemed to be no rule as to the timing of second-look endoscopy, although it was most frequently performed on the day after hemostasis. The recent outcomes of endoscopic treatment for nonmalignant gastroduodenal bleeding in Japan were excellent in both peptic and artificial ulcers with similar efficacies. Although they were minor findings, some differences in applied endoscopic methods, concomitant use of antisecretory drugs, and presence of second-look endoscopy were observed.