Hiroshi Takihara

Endoscopic submucosal dissection of cecal lesions in proximity to the appendiceal orifice

BACKGROUND AND STUDY AIMS Endoscopic submucosal dissection (ESD) is performed for treatment of various gastrointestinal lesions; however, the cecum in proximity to the appendiceal orifice remains a challenging area. We reviewed our experience with cecal ESD near the appendiceal orifice in order to clarify whether this procedure is a safe and effective therapeutic option. PATIENTS AND METHODS We retrospectively reviewed ESD for lesions within approximately 12 mm of the appendiceal orifice at Kobe University Hospital and an affiliated hospital between January 2003 and December 2014. Lesions were classified as: Type 0, proximity to the appendiceal orifice but does not reach it; Type 1, reaches border of the appendix, but does not enter orifice; Type 2, enters orifice, and transition to normal appendiceal mucosa is discernible on inspection of the appendiceal lumen; and Type 3, enters orifice deeply and tumor edge cannot be observed. ESD was not performed for Type 3 lesions unless appendectomy was performed prior to ESD. RESULTS A total of 76 lesions satisfied the inclusion criteria (47 Type 0 lesions, 20 Type 1, 6 Type 2, and 3 Type 3). En bloc resection was achieved in 72 lesions (94.7 %). Median specimen size was 49 mm (range 15 - 114 mm), and median tumor size was 35.5 mm (10 - 110 mm). One patient experienced postoperative bleeding, which was treated by endoscopic hemostasis. Another patient who experienced intraoperative perforation and was treated by clip closure later developed appendicitis; he underwent emergency ileocecal surgical resection. Another patient experienced postoperative appendicitis and recovered with antibiotic treatment. CONCLUSIONS ESD in close proximity to the appendiceal orifice seems safe and effective.

Feasibility and safety of endoscopic submucosal dissection for lesions involving the ileocecal valve

BACKGROUND AND STUDY AIM Endoscopic submucosal dissection (ESD) has been applied to treat early colorectal cancers. The aim of this study was to clarify the clinical course of ESD for lesions involving the ileocecal valve (ICV) by evaluating the successful resection rates, and the risk and frequency of adverse events. PATIENTS AND METHODS The outcome of ESD on 38 ICV lesions was compared with the outcome of 132 cecal lesions that did not involve the ICV or appendiceal orifice during the same study period. The factors related to longer procedure time, postoperative stricture development, and tumor recurrence were investigated for ESD of ICV lesions. RESULTS There was no significant difference between the ICV and non-ICV groups in the en block resection rates. The median procedure time was significantly longer in the ICV group than in the non-ICV group, with a point estimate of the difference of 37 minutes (95 % confidence interval [CI] 20.00 to 56.00; P  < 0.01). None of the patients developed symptomatic post-ESD stricture or tumor recurrence. ESD procedure duration was ≥ 120 minutes in 16 lesions and < 120 minutes in 22 lesions of the ICV group. A specimen diameter of ≥ 40 mm and tumor extension into terminal ileum were factors related to a longer procedure time (odds ratio [OR] 8.40, 95 %CI 1.53 to 46.10, P = 0.01; OR 10.60, 95 %CI 2.17 to 51.40, P  < 0.01, respectively). CONCLUSIONS ICV lesions can be resected by ESD without major adverse events or causing symptomatic stricture development. However, ESD for ICV lesions should be performed only by expert endoscopists, as the procedure requires accomplished endoscopic skill and experience.

A case of very large intrahepatic bile duct adenoma followed for 7 years

A 70-year-old man was referred to our hospital due to abnormal liver function. A tumor of 92 mm × 61 mm was detected on ultrasound screening of the left liver lobe. Although the tumor was suspected to be intrahepatic bile duct carcinoma, he had chronic heart disease and was unable to undergo surgery. Therefore, he was followed without further testing. No increase in tumor serum markers or tumor size was observed for the subsequent 7 years. We continued to suspect intrahepatic bile duct carcinoma, and we decided to perform a tumor biopsy. Tumor biopsy findings indicated intrahepatic bile duct adenoma (BDA), which is a rare benign epithelial liver tumor typically ranging from 1 mm to 20 mm. We herein report a case of very large BDA followed for 7 years.

Usefulness of a novel slim type FlushKnife-BT over conventional FlushKnife-BT in esophageal endoscopic submucosal dissection

AIM To investigated the usefulness of a novel slim type ball-tipped FlushKnife (FlushKnife-BTS) over ball-tipped FlushKnife (FlushKnife-BT) in functional experiments and clinical practice. METHODS In order to evaluate the functionality of FlushKnife-BTS, water aspiration speed, resistance to knife insertion through the scope, and waterjet flushing speed were compared between FlushKnife-BTS and BT. In clinical practice, esophageal endoscopic submucosal dissection (ESD) performed using FlushKnife-BTS or BT by an experienced endoscopist between October 2015 and January 2016 were retrospectively reviewed. The treatment speed and frequency of removing and reinserting the knife to aspirate fluid and air during ESD sessions were analyzed. RESULTS Functional experiments revealed that water aspiration speed by the endoscope equipped with a 2.8-mm working channel with FlushKnife-BTS was 7.7-fold faster than that with conventional FlushKnife-BT. Resistance to knife insertion inside the scope with a 2.8-mm working channel was reduced by 40% with FlushKnife-BTS. The waterjet flushing speed was faster with the use of FlushKnife-BT. In clinical practice, a comparison of 6 and 7 ESD using FlushKnife-BT and BTS, respectively, revealed that the median treatment speed was 25.5 mm2/min (range 19.6-30.3) in the BT group and 44.2 mm2/min (range 15.5-55.4) in the BTS group (P = 0.0633). However, the median treatment speed was significantly faster with FlushKnife-BTS when the resection size was larger than 1000 m2 (n = 4, median 24.2 mm2/min, range 19.6-27.7 vs n = 4, median 47.4 mm2/min, range 44.2-55.4, P = 0.0209). The frequency of knife replacement was less in the BTS group (median 1.76 times in one hour, range 0-5.45) than in the BT group (7.02 times in one hour, range 4.23-15) (P = 0.0065). CONCLUSION Our results indicate that FlushKnife-BTS enhances the performance of ESD, particularly for large lesions, by improving air and fluid aspiration and knife insertion during ESD and reducing the frequency of knife removal and reinsertion.

First reported case of per anal endoscopic myectomy (PAEM): A novel endoscopic technique for resection of lesions with severe fibrosis in the rectum

Background and study aims A 54-year-old man was diagnosed with a rectal tumor extending through the submucosal layer. The patient refused surgery and therefore endoscopic submucosal dissection (ESD) was pursued. The lesion exhibited the muscle retraction sign. After dissecting circumferentially around the fibrotic area by double tunneling method, a myotomy was performed through the internal circular muscle layer, creating a plane of dissection between the internal circular muscle layer and the external longitudinal muscle layer, and a myectomy was completed. The pathologic specimen verified T1b grade 1 sprouting adenocarcinoma with 4350 µm invasion into the submucosa with negative resection margins.

Efficacy of forced coagulation with low high-frequency power setting during endoscopic submucosal dissection

AIM To investigated the hemostatic ability of the S and F1-10 methods in clinical and ex vivo studies. METHODS The hemostatic abilities of the two methods were analyzed retrospectively in all six gastric endoscopic submucosal dissection cases. The treated vessel diameter, compressed vessel frequency, and bleeding frequency after cutting the vessels were noted by the recorded videos. The coagulation mechanism of the two power settings was evaluated using the data recording program and histological examination on macro- and microscopic levels in the ex vivo experiments using porcine tissues. RESULTS F1-10 method showed a significantly better hemostatic ability for vessels ≥ 2 mm in diameter and a trend of overall better coagulation effect, evaluated by the bleeding rate after cutting the vessels. F1-10 method could sustain electrical current longer and effectively coagulate the tissue wider and deeper than the S method in the porcine model. CONCLUSION F1-10 method is suggested to achieve a stronger hemostatic effect than the S method in clinical procedures and ex vivo models.

Peranal endoscopic myectomy (PAEM) for rectal lesions with severe fibrosis and exhibiting the muscle-retracting sign

BACKGROUND Although endoscopic submucosal dissection has enabled complete tumor resection and accurate pathological assessment in a manner that is less invasive than surgery, the complete resection of lesions with severe fibrosis in the submucosal layer and exhibiting the muscle-retracting sign is often difficult. We have devised a new method, peranal endoscopic myectomy (PAEM), for rectal lesions with severe fibrosis, in which dissection is performed between the inner circular and outer longitudinal muscles, and have examined the usefulness and safety of this new technique. METHODS All of the patients who underwent PAEM in our hospital and affiliated hospitals between July 2015 and June 2017 were retrospectively reviewed. RESULTS 10 rectal lesions were treated with PAEM. En bloc resection with a negative vertical margin was achieved in eight patients (80 %), whose lesions were mucosal (n = 2), shallow submucosal (n = 1), deep submucosal (n = 4), and muscle invasive (n = 1). The clinical course of all patients after PAEM was favorable. In patients who underwent additional surgery, anus preservation was achieved on the basis of the pathological results from PAEM. CONCLUSIONS PAEM for lesions with severe fibrosis exhibiting the muscle-retracting sign appears to be both safe and useful.

Medical Treatment of Postendoscopic Submucosal Dissection Phlegmonous Gastritis in an Elderly Diabetic Woman with Myelodysplastic Syndrome

Phlegmonous gastritis is a rare, suppurative disease characterized by full-thickness exudative changes, infiltration of inflammatory cells, and edema primarily in the submucosal layer. A 76-year-old woman with type 2 diabetes and myelodysplastic syndrome underwent endoscopic submucosal dissection (ESD) for early gastric cancer. Postoperatively, she developed persistent fever and computed tomography displayed full-circumference thickening of the gastric wall and increased levels of fat stranding. Endoscopy showed post-ESD ulcer floor expansion, formation of a false lumen between the ulcer floor and surrounding folds, and adhesion of purulent matter. Klebsiella pneumoniae, Pseudomonas aeruginosa, and Candida albicans were detected from pus culture and Klebsiella pneumoniae from blood culture, leading to a diagnosis of phlegmonous gastritis. Contrast examination showed no leakage outside the gastric wall; therefore, the patient fasted and was given antibiotics. She was successfully treated with medical therapy, as demonstrated by repeat endoscopy. Based on our experience, we recommend antibiotics before and after ESD in patients thought to be at high risk of infection, as well as careful postoperative management including postoperative endoscopy.