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).

Scissor-type knife significantly improves self-completion rate of colorectal endoscopic submucosal dissection: Single-center prospective randomized trial.

BACKGROUND AND AIM: Colorectal endoscopic submucosal dissection (C-ESD) is recognized as a difficult procedure. Recently, scissors-type knives were launched to reduce the difficulty of C-ESD. The aim of this study was to evaluate the efficacy and safety of the combined use of a scissors-type knife and a needle-type knife with a water-jet function (WJ needle-knife) for C-ESD compared with using the WJ needle-knife alone. METHODS: This was a prospective randomized controlled trial in a referral center. Eighty-five patients with superficial colorectal neoplasms were enrolled and randomly assigned to undergo C-ESD using a WJ needle-knife alone (Flush group) or a scissor-type knife-supported WJ needle-knife (SB Jr group). Procedures were conducted by two supervised residents. Primary endpoint was self-completion rate by the residents. RESULTS: Self-completion rate was 67% in the SB Jr group, which was significantly higher than that in the Flush group (39%, P = 0.01). Even after exclusion of four patients in the SB Jr group in whom C-ESD was completed using the WJ needle-knife alone, the self-completion rate was significantly higher (63% vs 39%; P = 0.03). Median procedure time among the self-completion cases did not differ significantly between the two groups (59 vs 51 min; P = 0.14). No fatal adverse events were observed in either group. CONCLUSIONS: In this single-center phase II trial, scissor-type knife significantly improved residents' self-completion rate for C-ESD, with no increase in procedure time or adverse events. A multicenter trial would be warranted to confirm the validity of the present study.

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.

Long-term survival after endoscopic resection for early gastric cancer in the remnant stomach: comparison with radical surgery.

BACKGROUND: Endoscopic resection (ER) has recently become standard treatment, even for early gastric cancer (EGC) in the remnant stomach. We aimed to compare long-term survival after ER versus radical surgery for EGC in the remnant stomach. METHODS: We retrospectively compared overall and cause-specific survival of patients who had undergone ER or radical surgery for EGC in the remnant stomach from 1998 to 2012. RESULTS: During the study period, 32 patients with intramucosal (M), two with shallow submucosal (SM1) and eight with deep submucosal (SM2) cancers had undergone ER (ER group) whereas six with M and seven with SM2 cancers had undergone surgery (surgery group). All patients were followed up for a median of 60 months; during follow up, 15 patients died, including three in the ER group with SM2 cancer who died of gastric cancer. The overall 5-year survival rates of M-SM1 and SM2 cancer patients in the ER and surgery groups were 89%, 48%, 80%, and 67%, respectively (P=0.079). The disease-specific 5-year survival rates of M-SM1 and SM2 cancer patients in the ER and surgery groups were 100%, 48%, 100%, and 100%, respectively (P=0.000). Operation time and hospital stay were significantly shorter in the ER than the surgery group (P<0.001). Grade 2 perforation occurred in two patients in the ER group and Grade 3 anastomotic leakage in two patients in the surgery group. CONCLUSION: ER provides excellent outcomes, comparable with those of radical surgery, in patients with M-SM1 gastric cancer in the remnant stomach; however, patients with SM2 cancer require radical surgery.

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

BACKGROUND AND AIMS: 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). METHODS: We performed a single-arm observational study of diagnostic accuracy in two stages, as follows: seeking stage, development of simple diagnostic features for SSA/P and definition of diagnostic criteria based on retrospective assessments of M-NBI; and validation stage, prospective validation and evaluation of the new diagnostic criteria. RESULTS: In the seeking stage, we identified brownish, oval, expanded crypt openings and thick-branched vessels on the surfaces of SSA/Ps. We named these "expanded crypt openings" (ECOs) and "thick and branched vessels" (TBVs), respectively. In the validation stage, we enrolled 796 polyps in 261 patients, and classified 126 polyps as NICE type 1; all these lesions were endoscopically removed and assessed histopathologically. The sensitivity, specificity, and accuracy of ECOs for SSA/Ps were 84.3%, 81.1%, and 82.4%, whereas those of TBVs were 45.1%, 68.9%, and 59.2%, respectively. M-NBI provided a sensitivity of 98% and specificity of 59.5% for discrimination of SSA/Ps from other lesions classified as NICE type 1. CONCLUSIONS: Identification of ECOs, supplemented with TBVs, has high sensitivity for the diagnosis of SSA/P. These findings may facilitate the use of endoscopic optical diagnosis in clinical practice.

Endoscopic optical diagnosis provides high diagnostic accuracy of esophageal squamous cell carcinoma.

BACKGROUND: Recent technological advances have stimulated the development of endoscopic optical biopsy technologies. This study compared the accuracy of endoscopic diagnosis using magnifying narrow-band imaging (NBI) and histologic diagnosis of esophageal squamous lesions. METHODS: Patients at high risk for esophageal squamous cell carcinoma were examined with endoscopy and subsequent biopsy. The lesions diagnosed as cancer on NBI and the lesions diagnosed as cancer on biopsy were resected endoscopically or surgically. Histological diagnoses of resected specimens, the reference standards in this study, were made by a pathologist who was blind to both the endoscopic and biopsy diagnoses. The primary outcome was the accuracy of endoscopic and biopsy diagnosis. A noninferiority trial design with a noninferiority margin of -10% was chosen to investigate the accuracy of endoscopic diagnosis using magnifying NBI. RESULTS: Between November 2010 and October 2012, a total of 111 lesions in 85 patients were included in the analysis. The accuracy of endoscopic diagnosis and biopsy diagnosis for all lesions was 91.0% (101/111) and 85.6% (95/111), respectively. The difference in diagnostic accuracy was 5.4% (95% confidence interval: -2.9%-13.7%). The accuracy of endoscopic diagnosis and biopsy diagnosis of invasive cancers was 94.9% (74/78) and 84.6% (66/78), respectively. The difference was 10.3% (95% confidence interval: 1.6%-19.0%) for invasive cancers. The lower bound of the 95% confidence interval was above the prestated -10% in both cases. CONCLUSION: Noninferiority of endoscopic diagnosis by magnifying NBI to histologic diagnosis by biopsy was established in this study (p = 0.0001). TRIAL REGISTRATION: The study was registered on 9th November 2010 in the University Hospital Medical Network Clinical Trials Registry as number: UMIN000004529.

Predictors of lymph node metastasis in T1 colorectal carcinoma: an immunophenotypic analysis of 265 patients.

BACKGROUND: The appropriateness of endoscopic resection in patients with T1 colorectal carcinomas is unclear. Highly precise predictors of lymph node metastasis are required to optimize the outcomes of treatments for T1 colorectal carcinomas. OBJECTIVE: The purpose of this work was to identify predictors of lymph node metastasis by examining the clinicopathologic significance of immunophenotypes found in T1 colorectal carcinomas. DESIGN: This was a retrospective study. SETTINGS: The study was conducted at a university hospital. PATIENTS: Included were 265 patients with T1 colorectal carcinoma who underwent radical surgery. INTERVENTIONS: Patients with T1 colorectal carcinoma were managed. MAIN OUTCOME MEASURES: Immunophenotypes were associated with various clinicopathologic parameters, and CD10 expression was strongly associated with lymph node metastasis. RESULTS: The levels of MUC2, MUC5AC, and CD10 expression were individually significantly associated with tumor location, growth pattern, histologic type, invasive potential, and metastatic potential. The incidence of lymph node metastasis was significantly associated with each of the 5 following parameters: depth of submucosal invasion (p = 0.005), tumor budding (p < 0.001), lymphatic invasion (p < 0.001), MUC2 expression (p = 0.006), and CD10 expression (p < 0.001). Multivariate analysis showed that CD10 expression (OR, 9.2 [95% CI, 2.5-39.8]; p = 0.001) and lymphatic invasion (OR, 6.3 [95% CI, 2.5-17.7]; p < 0.001) were independently associated with lymph node metastasis. LIMITATIONS: This study was limited by its small sample size, intraobserver variation attributed to immunohistochemical staining, and potential selection bias because surgically resected specimens were collected instead of endoscopically resected specimens. CONCLUSIONS: We suggest that CD10 expression is closely associated with lymph node metastasis in T1 colorectal carcinoma.

Pink-color sign in esophageal squamous neoplasia, and speculation regarding the underlying mechanism.

AIM: To investigate the reasons for the occurrence of the pink-color sign of iodine-unstained lesions. METHODS: In chromoendoscopy, the pink-color sign of iodine-unstained lesions is recognized as useful for the diagnosis of esophageal squamous cell carcinoma. Patients with superficial esophageal neoplasms treated by endoscopic resection were included in the study. Areas of mucosa with and without the pink-color sign were evaluated histologically. The following histologic features that were possibly associated with the pink-color sign were evaluated. The keratinous layer and basal cell layer were classified as present or absent. Cellular atypia was classified as high grade, moderate grade or low grade, based on nuclear irregularity, mitotic figures, loss of polarity, chromatin pattern and nuclear/cytoplasmic ratio. Vascular change was assessed based on dilatation, tortuosity, caliber change and variability in shape. Vessels with these four findings were classified as positive for vascular change. Endoscopic images of the lesions were captured immediately after iodine staining, 2-3 min after iodine staining and after complete fading of iodine staining. Quantitative analysis of color changes after iodine staining was also performed. RESULTS: A total of 61 superficial esophageal neoplasms in 54 patients were included in the study. The lesions were located in the cervical esophagus in one case, the upper thoracic esophagus in 10 cases, the mid-thoracic esophagus in 33 cases, and the lower thoracic esophagus in 17 cases. The median diameter of the lesions was 20 mm (range: 2-74 mm). Of the 61 lesions, 28 were classified as pink-color sign positive and 33 as pink-color sign negative. The histologic diagnosis was high-grade intraepithelial neoplasia (HGIN) or cancer invading into the lamina propria in 26 of the 28 pink-color sign positive lesions. There was a significant association between pink-color sign positive epithelium and HGIN or invasive cancer (P = 0.0001). Univariate analyses found that absence of the keratinous layer and cellular atypia were significantly associated with the pink-color sign. After Bonferroni correction, there were no significant associations between the pink-color sign and presence of the basal membrane or vascular change. Multivariate analyses found that only absence of the keratinous layer was independently associated with the pink-color sign (OR = 58.8, 95%CI: 5.5-632). Quantitative analysis was performed on 10 superficial esophageal neoplasms with both pink-color sign positive and negative areas in 10 patients. Pink-color sign positive mucosa had a lower mean color value in the late phase (pinkish color) than in the early phase (yellowish color), and had similar mean color values in the late and final phases. These findings suggest that pink-color positive mucosa underwent color fading from the color of the iodine (yellow) to the color of the mucosa (pink) within 2-3 min after iodine staining. Pink-color sign negative mucosa had similar mean color values in the late and early phases (yellowish color), and had a lower mean color value in the final phase (pinkish color) than in the late phase. These findings suggest that pink-color sign negative mucosa did not undergo color fading during the 2-3 min after iodine staining, and underwent color fading only after spraying of sodium thiosulfate. CONCLUSION: The pink-color sign was associated with absence of the keratinous layer. This sign may be caused by early fading of iodine staining.

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.

Pathological factors related to lymph node metastasis of submucosally invasive gastric cancer: criteria for additional gastrectomy after endoscopic resection.

BACKGROUND: There are currently no universally accepted indications and criteria for additional gastrectomy after endoscopic resection of submucosally invasive cancer. The purpose of the present study was to establish accurate indications and criteria for such additional gastrectomy on the basis of lymph node metastasis risk. METHODS: We investigated 130 submucosally invasive gastric cancers and analyzed the pathological risk factors for lymph node metastasis. The tumors were evaluated for pathological factors in the area of invasion, and factors were compared between the cases with lymph node metastasis and those without. RESULTS: Univariate logistic regression analysis showed that tumor minor axis length, depth of invasion, histological classification of the area of submucosal invasion, absence of lymphoid infiltration, ulceration or scar in the lesion, and lymphatic and venous invasion are statistically significant risk factors for lymph node metastasis. Multivariate logistic regression analysis showed that the absence of lymphoid infiltration and the presence of lymphatic invasion are statistically significant as risk factors for lymph node metastasis. CONCLUSIONS: We present a scoring system on the basis of the pathological criteria tested in this study. Our findings enable more accurate identification of patients who should undergo additional gastrectomy after endoscopic resection.

[One case that accompanied accessory papilla carcinoid for von Recklinghausen's disease].

A 45-year-old man: pointed out von Recklinghausen disease (following vR disease) in 18 years old. He had a checkup in a close inspection purpose of a duodenum tumor at our hospital. We diagnosis that the accessory papilla carcinoid, and Pancreas Divisum was doubted. Rocal resection of the accessory papilla was performed and picked out carcinoid of 7 mm size. In literatures searches, as for accessory papilla carcinoid, merger frequency of a papilla tumor was high in the example, and merged, vR disease of lymph node metastasis.