Kohei Takizawa

Routine coagulation of visible vessels may prevent delayed bleeding after endoscopic submucosal dissection - An analysis of risk factors

BACKGROUND AND STUDY AIM Endoscopic submucosal dissection (ESD) has been reported to be associated with a higher complication rate than standard endoscopic mucosal resection. We aimed to clarify the risk factors for delayed bleeding after ESD for early gastric cancer (EGC). METHODS 1083 EGCs in 968 consecutive patients undergoing ESD during a 4-year period were reviewed. Post-ESD coagulation (PEC) preventive therapy of visible vessels in the resection area, using a coagulation forceps, was introduced and mostly performed during the later 2 years. Various factors related to patients, tumors, and treatment including PEC were investigated using univariate and multivariate analysis with regard to delayed post-ESD bleeding, evidenced by hematemesis or melena, that required endoscopic treatment. RESULTS Delayed bleeding occurred after ESD of 63 lesions (5.8 % of all lesions and 6.5 % of patients), controlled in all cases by endoscopic hemostasis; blood transfusion was required in only one case. Tumor location in the upper third of the stomach and PEC were independent factors indicating a lower rate of delayed bleeding according to both univariate and multivariate analysis. CONCLUSIONS This retrospective study suggested that preventive coagulation of visible vessels in the resection area after ESD may lead to a lower bleeding rate.

Usefulness of a novel electrosurgical knife, the insulation-tipped diathermic knife-2, for endoscopic submucosal dissection of early gastric cancer

BackgroundAlthough endoscopic submucosal dissection (ESD) of early gastric cancer using an insulation-tipped diathermic (IT) knife enables the removal of large and ulcerative lesions en bloc, expert endoscopic skill is required. We developed an improved IT knife (IT-2) and compared its efficacy and safety with that of the original IT knife (IT-OM).MethodsWe performed ESD of 602 gastric cancers. Of these, 314 previously untreated single lesions of initial onset were analyzed. Operating time, rate of en-bloc resection, and incidence of complications were compared in the IT-2 group (161 patients) and IT-OM group (153 patients). Lesions were further analyzed as to whether they met the Japanese Gastric Cancer Association indications for ESD or extended indications.ResultsMean resection time was significantly shorter in the IT-2 than in the IT-OM group (48 vs 63 min). There were fewer surgeries lasting longer than 2 h in the IT-2 group than in the IT-OM group (3% vs 12%). En-bloc and margin-free resection rates in the IT-OM and IT-2 groups were 95% and 99%, respectively. Perforations occurred in 3.9% of patients in the IT-OM group and in 5% of patients in the IT-2 group (difference not significant [NS]). The incidence of postoperative hemorrhage was 7.8% in the IT-OM group and 8.7% in the IT-2 group (NS). In both groups, complications were treated endoscopically, and emergency surgery was unnecessary.ConclusionResectability and complication rates were similar in the two groups. However, operating time was shorter with IT-2, irrespective of the indications for the performance of ESD. This study suggests benefits of the IT-2 over the IT-OM.

Endoscopic Submucosal Dissection of Early Gastric Cancer

Endoscopic mucosal resection (EMR) of early gastric cancer (EGC) without any risk of lymph node metastasis was developed in Japan in the 1980s, and it has been one of the standard treatments of EGC for nearly 20 years. Recently, several EMR techniques developed in Japan have been accepted and done in Western countries. These EMR techniques are safe and efficacious but unsuitable for large lesions. Because we could not remove a large lesion in 1 fragment, which was very important for the precise diagnosis of tumor depth, local recurrence increased in large-lesion cases. An innovative procedure using newly developed endoscopic knives, called endoscopic submucosal dissection (ESD), was developed in the late 1990s, which made it possible to remove a large lesion en bloc. Theoretically, ESD has no limitation with respect to tumor size; therefore, it is expected to replace the surgical treatment in some situations. Although ESD has spread throughout Japan within a short period, there remain several disadvantages, such as a higher incidence of complications and a requirement of higher endoscopic skills compared to those of conventional EMR methods. The endoscopic indications, procedures, complications and treatment outcomes of the ESD of EGC are described in this review.

Characteristics of autoimmune pancreatitis based on serum IgG4 level.

BACKGROUND Autoimmune pancreatitis is categorized as an IgG4-related autoimmune disease, mostly associated with serological alterations, however characteristics of autoimmune pancreatitis based on serum markers have not been fully evaluated. METHODS We evaluated demographics, symptoms, imaging and therapeutic outcome in 27 cases of autoimmune pancreatitis stratified by serum IgG4 level. RESULTS Twenty patients (74%) had elevated serum IgG4 and 7 (26%) had normal IgG4 levels. Compared to patients with normal serum IgG4 levels, patients with elevated IgG4 had higher incidence of jaundice at onset (14.3% vs. 80%, respectively; P=0.002), more frequent diffuse pancreatic enlargement at imaging (14.3% vs. 60%, respectively; P=0.04), significantly higher 18F-2-fluoro-2-deoxy-d-glucose uptake of pancreatic lesions (SUV max: 4.0 vs. 5.7, respectively; P=0.02), more frequent extrapancreatic lesions (42.9% vs. 85%, respectively; P=0.03). Response to steroids was recognized regardless of serum IgG4 level, however maintenance therapy was required more frequently amongst patients with elevated compared to normal IgG4 (85.7% vs. 33.3%, respectively; P=0.04). CONCLUSIONS Clinical features of autoimmune pancreatitis are different based on level of serum IgG4. Further studies are needed to clarify if normal serum IgG4 cases are a precursor of active type 1 or type 2 autoimmune pancreatitis.

Discrepancies in histologic diagnoses of early gastric cancer between biopsy and endoscopic mucosal resection specimens

BackgroundA preoperative histologic diagnosis of neoplasia is a requirement for endoscopic resection (ER). However, discrepancies may occur between histologic diagnoses based on biopsy specimens versus ER specimens. The aim of this study was to assess the rate of discrepancy between histologic diagnoses from biopsy specimens and ER specimens.MethodsA total of 1705 gastric lesions, from 1419 patients with a biopsy diagnosis of neoplasia, were treated by ER from September 2002 to December 2008. We compared the histologic diagnosis from the biopsy sample and the final diagnosis from the ER specimen to assess the discrepancy rate. Clinicopathological characteristics of the lesions that were related to the histologic discrepancies were also studied.ResultsAn ER diagnosis of gastric cancer was made in 49% (118/241) of lesions diagnosed as borderline lesions from biopsy specimens; this included adenomas and lesions difficult to diagnose as regenerative or neoplastic. The size, existence of a depressed area, and ulceration findings were significant factors observed in these lesions. An ER diagnosis of differentiated type cancer was obtained for 17% (12/63) of lesions diagnosed as undifferentiated type cancer from the biopsy specimens; for these lesions, the color and a mixed histology were significant factors related to the histologic discrepancies.ConclusionA biopsy diagnosis of borderline lesions or undifferentiated type cancer is more likely to disagree with the diagnosis from ER specimens. Endoscopic characteristics should be considered together with the biopsy diagnosis to determine the treatment strategy for these lesions.

Preoperative indicators of failure of en bloc resection or perforation in colorectal endoscopic submucosal dissection: implications for lesion stratification by technical difficulties during stepwise training.

BACKGROUND AND AIMS The technical difficulties inherent in endoscopic submucosal dissection (ESD) for colorectal neoplasms may result in the failure of en bloc resection or perforation. The aim of this retrospective study was to assess the predictors of en bloc resection failure or perforation by using preoperatively available factors. METHODS Between September 2002 and March 2013, 716 colorectal ESDs in 673 consecutive patients were performed at a tertiary cancer center. Patient characteristics, tumor location, tumor type, colonoscopy-related factors, and endoscopist experience were assessed based on a prospectively recorded institutional ESD database. Logistic regression analysis was performed to identify predictors of failure of en bloc resection or perforations, with subgroup analyses of ESDs performed by endoscopists less experienced in colorectal ESD (<40 cases) and for colonic lesions only. RESULTS On multivariate analysis, independent predictors of failure of en bloc resection or perforations were the presence of fold convergence (odds ratio [OR] 4.4; 95% confidence interval [95% CI], 1.9-9.9), protruding type (OR 3.6; 95% CI, 1.8-7.1), poor endoscope operability (OR 3.5; 95% CI, 1.8-6.9), right-sided colonic lesions (OR 3.0; 95% CI, 1.5-6.3 vs rectal lesions), left-sided colonic lesions (OR 3.2; 95% CI, 1.7-6.3, vs rectal lesions), the presence of an underlying semilunar fold (OR 2.1; 95% CI, 1.3-3.6), and a less-experienced endoscopist (OR 2.1; 95% CI, 1.3-3.6). Among less-experienced endoscopists, colonic lesions were independent predictors (right-sided colonic lesions 8.1; 95% CI, 2.9-25.1; left-sided colonic lesions 8.1; 95% CI, 2.5-28.3 vs rectal lesions). For colonic lesions, the presence of fold convergence (OR 3.7; 95% CI, 1.6-8.6), poor endoscope operability (OR 3.6; 95% CI, 1.8-7.2), a less-experienced endoscopist (OR 3.0; 95% CI, 1.7-1.8), and the presence of an underlying semilunar fold (OR 2.7; 95% CI, 1.5-4.7) were identified predictors. CONCLUSION This study successfully identified predictors of en bloc resection failure or perforation. Understanding these indicators could help to accurately stratify lesions according to technical difficulty and to appropriately select endoscopists.

Clinical outcomes of endoscopic submucosal dissection for early gastric cancer in remnant stomach or gastric tube.

BACKGROUND AND STUDY AIMS Little information exists regarding the optimal treatment of early gastric cancer (EGC) in a remnant stomach or gastric tube. The aim of this study was to assess the feasibility and clinical outcomes of endoscopic submucosal dissection (ESD) for EGC in a remnant stomach and gastric tube. PATIENTS AND METHODS Between September 2002 and December 2009, ESD was performed in 62 lesions in 59 patients with EGC in a remnant stomach (48 lesions) or gastric tube (14 lesions). Clinicopathological data were retrieved retrospectively to assess the en bloc resection rate, complications, and outcomes. Treatment results were assessed according to the indications for endoscopic resection, and were compared with those of ESD performed in a whole stomach during the same study period. RESULTS The en bloc resection rates for lesions within the standard and expanded indication were 100 % and 93 %, respectively. Postoperative bleeding occurred in five patients (8 %). The perforation rate was significantly higher (18 %, 11 /62) than that of ESD in a whole stomach (5 %, 69 /1479). Among the perforation cases, eight lesions involved the anastomotic site or stump line, and ulcerative changes were observed in five lesions. The 3-year overall survival rate was 85 %, with eight deaths due to other causes and no deaths from gastric cancer. CONCLUSION A high en bloc resection rate was achieved by ESD for EGC in a remnant stomach or gastric tube; however, this procedure is still technically demanding due to the high complication rate of perforation.

Treatment for superficial non-ampullary duodenal epithelial tumors

Because of the low prevalence of non-ampullary duodenal epithelial tumors (NADETs), standardized clinical management of sporadic superficial NADETs, including diagnosis, treatment, and follow-up, has not yet been established. Retrospective studies have revealed certain endoscopic findings suggestive of malignancy. Duodenal adenoma with high-grade dysplasia and mucosal cancer are candidates for local resection by endoscopic or minimally invasive surgery. The use of endoscopic treatment including endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), for the treatment for superficial NADETs is increasing. EMR requires multiple sessions to achieve complete remission and repetitive endoscopy is needed after resection. ESD provides an excellent complete resection rate, however it remains a challenging method, considering the high risk of intraoperative or delayed perforation. Minimally invasive surgery such as wedge resection and pancreas-sparing duodenectomy are beneficial for superficial NADETs that are technically difficult to remove by endoscopic treatment. Pancreaticoduodenectomy remains a standard surgical procedure for treatment of duodenal cancer with submucosal invasion, which presents a risk of lymph node metastasis. Endoscopic or surgical treatment outcomes of superficial NADETs without submucosal invasion are satisfactory. Establishing an endoscopic diagnostic tool to differentiate superficial NADETs between adenoma and cancer as well as between mucosal and submucosal cancer is required to select the most appropriate treatment.

Factors related to lateral margin positivity for cancer in gastric specimens of endoscopic submucosal dissection.

Background:  With the widespread use of endoscopic submucosal dissection (ESD), more large early gastric cancers (EGC) have become candidates for endoscopic resection. A precise diagnosis of the extent of cancer is indispensable to obtain R0 resection. The aim of the present study was to clarify the factors related to lateral margin positivity for cancer in specimens resected by ESD for EGC.

Risk of pancreatitis after endoscopic retrograde cholangiopancreatography and endoscopic biliary drainage

BACKGROUND Pancreatitis is the most common and serious complication to occur after endoscopic retrograde cholangiopancreatography (ERCP). It is often associated with additional diagnostic modalities and/or treatment of obstructive jaundice. The aim of this study was to determine the risk of post-ERCP pancreatitis associated with pancreaticobiliary examination and endoscopic biliary drainage (EBD). METHODS A total of 740 consecutive ERCP procedures performed in 477 patients were analysed for the occurrence of pancreatitis. These included 470 EBD procedures and 167 procedures to further evaluate the pancreaticobiliary tract using brush cytology and/or biopsy, intraductal ultrasound and/or peroral cholangioscopy or peroral pancreatoscopy. The occurrence of post-ERCP pancreatitis was analysed retrospectively. RESULTS The overall incidence of post-ERCP pancreatitis was 3.9% (29 of 740 procedures). The risk factors for post-ERCP pancreatitis were: being female (6.5%; odds ratio [OR] 2.5, P= 0.02); first EBD procedure without endoscopic sphincterotomy (ES) (6.9%; OR 3.0, P= 0.003), and performing additional diagnostic procedures on the pancreatobiliary duct (9.6%; OR 4.6, P < 0.0001). Pancreatitis after subsequent draining procedures was rare (0.4%; OR for first-time drainage 16.6, P= 0.0003). Furthermore, pancreatitis was not recognized in 59 patients who underwent ES. Seven patients with post-EBD pancreatitis were treated with additional ES. CONCLUSIONS Invasive diagnostic examinations of the pancreaticobiliary duct and first-time perampullary biliary drainage without ES were high-risk factors for post-ERCP pancreatitis. Endoscopic sphincterotomy may be of use to prevent post-EBD pancreatitis.