Takeshi Yamashina

Long-Term Outcome and Metastatic Risk After Endoscopic Resection of Superficial Esophageal Squamous Cell Carcinoma

OBJECTIVES:Long-term outcomes after endoscopic resection (ER) provide important information for the treatment of esophageal carcinoma. This study aimed to investigate the rates of survival and metastasis after ER of esophageal carcinoma.METHODS:From 1995 to 2010, 570 patients with esophageal carcinoma were treated by ER. Of these, the 402 patients with squamous cell carcinoma (280 epithelial (EP) or lamina propria (LPM) cancer, 70 muscularis mucosa (MM) cancer, and 52 submucosal (SM) cancer) were included in our analysis. Seventeen patients had cancer invading into the submucosa up to 0.2 mm (SM1) and 35 patients had cancer invading into the submucosa more than 0.2 mm (SM2).RESULTS:The mean (range) follow-up time was 50 (4–187) months. The 5-year overall survival rates of patients with EP/LPM, MM, and SM cancer were 90.5, 71.1, and 70.8%, respectively (P=0.007). Multivariate analysis identified depth of invasion and age as independent predictors of survival, with hazard ratios of 3.6 for MM cancer and 3.2 for SM cancer compared with EP/LPM cancer, and 1.07 per year of age. The cumulative 5-year metastasis rates in patients with EP/LPM, MM, SM1, and SM2 cancer were 0.4, 8.7, 7.7, and 36.2%, respectively (P<0.001). Multivariate analysis identified depth of invasion as an independent risk factor for metastasis, with hazard ratios of 13.1 for MM, 40.2 for SM1, and 196.3 for SM2 cancer compared with EP/LPM cancer. The cumulative 5-year metastasis rates in patients with mucosal cancer with and without lymphovascular involvement were 46.7 and 0.7%, respectively (P<0.0001).CONCLUSIONS:The long-term risk of metastasis after ER was mainly associated with the depth of invasion. This risk should be taken into account when considering the indications for ER.

Factors predicting perforation during endoscopic submucosal dissection for gastric cancer.

BACKGROUND Perforation is a common complication of endoscopic submucosal dissection (ESD), but little is known about the relevant risk factors. OBJECTIVE To investigate the risk factors for perforation. DESIGN Retrospective study. SETTING A cancer referral center. PATIENTS A total of 1795 early gastric tumors in 1500 patients treated by ESD from July 2002 to December 2010 were included in the analysis. MAIN OUTCOME MEASUREMENTS The associations between the incidence of perforation and patient and lesion characteristics were investigated. RESULTS Perforation during ESD occurred in 50 lesions (2.8%). Univariate analysis identified tumor location (upper, middle, or lower stomach), tumor diameter (≤ 20 or >20 mm), and treatment period (lesions treated in the first or second period) as predictors of perforation. Multivariate analysis identified tumor location (upper stomach), tumor diameter (>20 mm), and treatment period (first half) as independent risk factors for perforation. The odds ratios were 2.4 (95% CI, 1.3-4.7; P = .006) for lesions in the upper stomach and 1.9 (95% CI, 1.0-3.5; P = .04) for lesions larger than 20 mm. Perforation risks were 5.4% for lesions in the upper stomach and 4.4% for lesions larger than 20 mm. Three patients required emergency surgery, but the rest of the patients were successfully treated with endoscopic clipping. There was no perforation-related mortality. LIMITATIONS Single-center, retrospective study design. CONCLUSIONS Lesions in the upper stomach and lesions larger than 20 mm were independent risk factors for perforation during ESD. Patients should be made aware of the estimated high risks of these lesions before undergoing ESD.

Delayed perforation: A hazardous complication of endoscopic resection for non-ampullary duodenal neoplasm

Perforation is a major complication of endoscopic resection for gastrointestinal neoplasms. However, little is known about delayed perforation after endoscopic resection for non‐ampullary duodenal neoplasm. The aim of the present study was to investigate the clinical features of delayed perforation after endoscopic resection for non‐ampullary duodenal neoplasm.

Diagnostic features of sessile serrated adenoma/polyps on magnifying narrow band imaging: A prospective study of diagnostic accuracy

The narrow band imaging classification system (NBI International Colorectal Endoscopic [NICE] classification) classifies colorectal polyps very accurately. However, sessile serrated adenoma/polyps (SSA/Ps) pathologically resembles hyperplastic polyp and has a possibility to be left in situ on NICE classification. The aim of this study was to establish and evaluate new simple diagnostic features for SSA/Ps using magnifying narrow band imaging (M‐NBI).

Scheduled second-look endoscopy is not recommended after endoscopic submucosal dissection for gastric neoplasms (the SAFE trial): a multicentre prospective randomised controlled non-inferiority trial

Objective To clarify the effectiveness of second-look endoscopy (SLE) at preventing bleeding after gastric endoscopic submucosal dissection (ESD). Design A multicentre prospective randomised controlled non-inferiority trial was conducted at five referral institutions across Japan. Patients with a solitary gastric neoplasm were enrolled. Exclusion criteria were previous oesophagogastric surgery or radiation therapy; perforation and the administration of antithrombotics, steroids or non-steroidal anti-inflammatory drugs. Patients were assigned to the SLE group or the non-SLE group by a computer-generated random sequence after ESD and were treated perioperatively with a proton pump inhibitor. SLE was performed one day after ESD. The primary endpoint was post-ESD bleeding, defined as an endoscopically proven haemorrhage. The trial had the power to detect a non-inferiority criterion of 7% between the groups. Results From February 2012 to February 2013, 130 and 132 patients were assigned to the SLE and the non-SLE groups, respectively. All patients were included in the intention-to-treat analysis of the primary endpoint. Post-ESD bleeding occurred in seven patients with (5.4%) SLE and five patients with (3.8%) non-SLE (risk difference −1.6% (95% CI −6.7 to 3.5); pnon-inferiority<0.001), meeting the non-inferiority criterion. All 12 patients with post-ESD bleeding and one patient with a delayed perforation were successfully managed with conservative treatment. Conclusions SLE after gastric ESD is not routinely recommended because it does not contribute to the prevention of post-ESD bleeding for patients with an average bleeding risk. Trial registration number UMIN-CTR000007170.

Features of electrocoagulation syndrome after endoscopic submucosal dissection for colorectal neoplasm.

Endoscopic submucosal dissection (ESD) is a promising treatment for large gastrointestinal superficial neoplasms, although it is technically difficult, and perforation and delayed bleeding are well‐known adverse events. However, there have been no large studies about electrocoagulation syndrome after colorectal ESD. The aim of this study was to evaluate the incidence and clinical significant risk factors of post‐ESD coagulation syndrome (PECS).

Feasibility of cold snare polypectomy in Japan: A pilot study

AIM To investigate the feasibility of cold snare polypectomy (CSP) in Japan. METHODS The outcomes of 234 non-pedunculated polyps smaller than 10 mm in 61 patients who underwent CSP in a Japanese referral center were retrospectively analyzed. The cold snare polypectomies were performed by nine endoscopists with no prior experience in CSP using an electrosurgical snare without electrocautery. RESULTS CSPs were completed for 232 of the 234 polyps. Two (0.9%) polyps could not be removed without electrocautery. Immediate postpolypectomy bleeding requiring endoscopic hemostasis occurred in eight lesions (3.4%; 95%CI: 1.1%-5.8%), but all were easily managed. The incidence of immediate bleeding after CSP for small polyps (6-9 mm) was significantly higher than that of diminutive polyps (≤ 5 mm; 15% vs 1%, respectively). Three (5%) patients complained of minor bleeding after the procedure but required no intervention. The incidence of delayed bleeding requiring endoscopic intervention was 0.0% (95%CI: 0.0%-1.7%). In total, 12% of the resected lesions could not be retrieved for pathological examination. Tumor involvement in the lateral margin could not be histologically assessed in 70 (40%) lesions. CONCLUSION CSP is feasible in Japan. However, immediate bleeding, retrieval failure and uncertain assessment of the lateral tumor margin should not be underestimated. Careful endoscopic diagnosis before and evaluation of the tumor residue after CSP are recommended when implementing CSP in Japan.

Traction-assisted colonic endoscopic submucosal dissection using clip and line: a feasibility study

Background and study aims: Colonic endoscopic submucosal dissection (ESD) is a challenging procedure because it is often difficult to maintain good visualization of the submucosal layer. To facilitate colonic ESD, we designed a novel traction method, namely traction-assisted colonic ESD using clip and line (TAC), and investigated its feasibility. Patients and methods: We retrospectively analyzed 23 patients with large colonic superficial lesions who had undergone TAC. The main outcome was the procedural success rate of TAC, which we defined as successful, sustained application of clip and line to the lesion until the end of the procedure. Results: The procedural success rate of TAC was 87 % (20/23). In all three unsuccessful cases, the lesions were in the proximal colon and the procedure times over 100 minutes. The overall mean procedure time was 61 min (95 % confidence interval, 18 – 172 min). We achieved en bloc resections of all lesions. There were no perforations or fatal adverse events. Conclusions: TAC is feasible and safe for colonic ESD and may improve the ease of performing this procedure.

Incomplete resection rate of cold snare polypectomy: a prospective single-arm observational study

Background and study aims Cold snare polypectomy (CSP) is considered to be safe for the removal of subcentimeter colorectal polyps. This study aimed to determine the rate of incomplete CSP resection for subcentimeter neoplastic polyps at our center. Patients and methods Patients with small or diminutive adenomas (diameter 1 - 9 mm) were recruited to undergo CSP until no polyp was visible. After CSP, a 1 - 3 mm margin around the resection site was removed using endoscopic mucosal resection. The polyps and resection site marginal specimens were microscopically evaluated. Incomplete resection was defined as the presence of neoplastic tissue in the marginal specimen. We also calculated the frequency at which the polyp lateral margins could be assessed for completeness of resection. Results A total of 307 subcentimeter neoplastic polyps were removed from 120 patients. The incomplete resection rate was 3.9 % (95 % confidence interval [CI] 1.7 % - 6.1 %); incomplete resection was not associated with polyp size, location, morphology, or operator experience. The polyp lateral margins could not be assessed adequately for 206 polyps (67.1 %). Interobserver agreement between incomplete resection and lateral polyp margins that were inadequate for assessment was poor (κ = 0.029, 95 %CI 0 - 0.04). Female sex was an independent risk factor for incomplete resection (odds ratio 4.41, 95 %CI 1.26 - 15.48; P  = 0.02). Conclusions At our center, CSP resection was associated with a moderate rate of incomplete resection, which was not associated with polyp characteristics. However, adequate evaluation of resection may not be routinely possible using the lateral margin from subcentimeter polyps that were removed using CSP.Trial registered at University Hospital Medical Information Network (UMIN 000010879).

Randomized Study of Two Endo-knives for Endoscopic Submucosal Dissection of Esophageal Cancer

OBJECTIVES:Settings for endoscopic submucosal dissection (ESD) of esophageal cancer have not been standardized, and no studies have directly compared ESD devices in humans.METHODS:We conducted a randomized study to compare the performances of two different endo-knives, the Flush knife and Mucosectom, for esophageal ESD in 48 lesions. All procedures were initiated by two endoscopists, who were assisted by senior endoscopists with verbal advice. In the Flush-knife group, mucosal incision with a 2-mm Flush knife was followed by submucosal dissection using a 1-mm Flush knife. In the Mucosectom group, mucosal incision with a 2-mm Flush knife was followed by submucosal dissection with a Mucosectom. The primary outcome variable was the procedure time required for submucosal dissection. The secondary outcome variables were total procedure time, self-completion rates, and adverse events.RESULTS:Total procedure time in the Mucosectom group was significantly shorter than in the Flush-knife group (57±21 vs. 83±27 min, respectively; P<0.001). The submucosal-dissection time in the Mucosectom group was significantly shorter than in the Flush-knife group (40±18 vs. 61±23 min, respectively; P<0.001). The self-completion rate in the Mucosectom group was slightly higher than in the Flush-knife group, but the difference was not significant (91.7% vs. 75%, respectively; P=0.25). One perforation and one postoperative bleeding occurred in the Flush-knife group, both of which were treated successfully by endoscopic treatment.CONCLUSIONS:The Mucosectom reduced the procedure and submucosal-dissection times of esophageal ESD, without increasing adverse events.