Kengo Nagai

Intralesional steroid injection to prevent stricture after endoscopic submucosal dissection for esophageal cancer: a controlled prospective study

BACKGROUND AND STUDY AIMS The frequency of stricture after endoscopic submucosal dissection (ESD) for esophageal squamous cell carcinoma with a mucosal defect involving more than three-quarters of the circumference is 70% - 90%. Stricture decreases quality of life and requires multiple endoscopic balloon dilation (EBD) sessions. We investigated the efficacy and safety of a single session of intralesional steroid injections to prevent post-ESD stricture. PATIENTS AND METHODS We conducted a prospective study on 30 patients with esophageal squamous cell carcinoma treated by ESD, who had a more than three-quarter but less than whole circumferential defect. A single session of intralesional steroid injections was undertaken immediately after ESD. Esophagogastroduodenoscopy was performed whenever patients reported dysphagia and 2 months after ESD in patients without dysphagia. Results were compared with a historical control group of 29 patients who underwent ESD without intralesional steroid injection. The primary endpoint was the post-ESD stricture rate. Secondary endpoints were the number of EBD sessions and the complication rate. RESULTS Compared with the historical control group, the study group had a significantly lower stricture rate (10%, 3/30 patients vs. 66%, 19/29 patients; P < 0.0001) and a lower number of EBD sessions (median 0, range 0 - 2 vs. median 2, range 0 - 15; P < 0.0001). The study group had a complication rate of 7 % (2 /30 patients), comprising a submucosal tear in one patient and bleeding in another, which were not a direct result of EBD. CONCLUSIONS A single session of intralesional steroid injections showed promising results for the prevention of stricture after ESD for esophageal cancer.

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.

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).

Comprehensive Investigation of Areae Gastricae Pattern in Gastric Corpus using Magnifying Narrow Band Imaging Endoscopy in Patients with Chronic Atrophic Fundic Gastritis

Background:  Barium radiographic studies have suggested the importance of evaluating areae gastricae pattern for the diagnosis of gastritis. Significance of endoscopic appearance of areae gastricae in the diagnosis of chronic atrophic fundic gastritis (CAFG) was investigated by image‐enhanced endoscopy.

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.

Integrated diagnostic strategy for the invasion depth of early gastric cancer by conventional endoscopy and EUS

BACKGROUND Although conventional endoscopy (CE) and EUS are considered useful for predicting the invasion depth (T-staging) in early gastric cancer (EGC), no effective diagnostic strategy has been established. OBJECTIVE To produce simple CE criteria and to elucidate an efficient diagnostic method by combining CE and EUS for accurate T-staging. DESIGN Single-center retrospective analysis. SETTING Academic university hospital. PATIENTS Consecutive patients with EGC from April 2007 to March 2012 who underwent CE and EUS before treatment. INTERVENTIONS Recorded endoscopic images were independently reviewed by 3 observers. The CE criteria for massive invasion were defined, and their utility and the additional value of EUS were assessed. MAIN OUTCOME MEASUREMENTS The accuracy of CE based on the criteria and the accuracy of EUS. RESULTS Two hundred thirty patients were enrolled: 195 with mucosal cancer or cancer in the submucosa less than 500 μm from the muscularis mucosae and 35 with invasive cancers. Multivariate analysis of the CE findings by 1 observer revealed that an irregular surface and a submucosal tumor-like marginal elevation were significantly associated with massive invasion. The simple CE criteria, consisting of those 2 features, had an overall accuracy of 73% to 82% and no significant differences in the diagnostic yield compared with EUS in all observers. CE accurately revealed mucosal cancer, and EUS efficiently salvaged the lesions that were over-diagnosed by CE. With our strategy, which involved the CE criteria and the optimal use of EUS, the comprehensive accuracy exceeded 85% in each observer. LIMITATIONS Retrospective, single-center study. CONCLUSIONS We demonstrated a practical strategy for T-staging in EGC using simple CE criteria and EUS.

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.

Clinical outcomes of endoscopic mucosal resection and endoscopic submucosal dissection as a transoral treatment for superficial pharyngeal cancer.

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have been introduced for the treatment of superficial pharyngeal cancer.