Yasuki Hori

Predictive factors for pancreatitis and cholecystitis in endoscopic covered metal stenting for distal malignant biliary obstruction

Pancreatitis and cholecystitis are major complications after self‐expandable metal stent (SEMS) placement in distal malignant biliary obstruction. We aimed to clarify predictive factors for pancreatitis and cholecystitis after covered SEMS placement.

Comparison of intraductal ultrasonography findings between primary sclerosing cholangitis and IgG4-related sclerosing cholangitis

Comparisons of intraductal ultrasonography (IDUS) findings between primary sclerosing cholangitis (PSC) and IgG4‐related sclerosing cholangitis (IgG4‐SC) have not been elucidated. We aimed to clarify the differences in transpapillary IDUS findings between PSC and IgG4‐SC.

Chemopreventive effect of resveratrol and apocynin on pancreatic carcinogenesis via modulation of nuclear phosphorylated GSK3β and ERK1/2

Despite progress in clinical cancer medicine in multiple fields, the prognosis of pancreatic cancer has remained dismal. Recently, chemopreventive strategies using phytochemicals have gained considerable attention as an alternative in the management of cancer. The present study aimed to evaluate the chemopreventive effects of resveratrol (RV) and apocynin (AC) in N-Nitrosobis(2-oxopropyl)amine-induced pancreatic carcinogenesis in hamster. RV- and AC-treated hamsters showed significant reduction in the incidence of pancreatic cancer with a decrease in Ki-67 labeling index in dysplastic lesions. RV and AC suppressed cell proliferation of human and hamster pancreatic cancer cells by inhibiting the G1 phase of the cell cycle with cyclin D1 downregulation and inactivation of AKT-GSK3β and ERK1/2 signaling. Further, decreased levels of GSK3βSer9 and ERK1/2 phosphorylation and cyclin D1 expression in the nuclear fraction were observed in cells treated with RV or AC. Nuclear expression of phosphorylated GSK3βSer9 was also decreased in dysplastic lesions and adenocarcinomas of hamsters treated with RV or AC in vivo. These results suggest that RV and AC reduce phosphorylated GSK3βSer9 and ERK1/2 in the nucleus, resulting in inhibition of the AKT-GSK3β and ERK1/2 signaling pathways and cell cycle arrest in vitro and in vivo. Taken together, the present study indicates that RV and AC have potential as chemopreventive agents for pancreatic cancer.

Feasibility of endoscopic retrograde cholangiopancreatography-related procedures in hemodialysis patients

The opportunities of endoscopic retrograde cholangiopancreatography (ERCP)‐related procedure for hemodialysis (HD) patients have been increasing recently. However, the complication rate of ERCPs in HD patients has not been evaluated sufficiently. We aimed to clarify the feasibility of ERCPs in HD patients.

Clinical evaluation of international consensus diagnostic criteria for type 1 autoimmune pancreatitis in comparison with Japanese diagnostic criteria 2011.

Objectives The objective of this study was to evaluate the International Consensus Diagnostic Criteria (ICDC) for type 1 autoimmune pancreatitis (AIP) in comparison with the Japanese criteria 2011 (JPS2011). Methods We retrospectively investigated the usefulness of ICDC in comparison with JPS2011 in 64 patients with AIP and 90 patients with pancreatic cancer. Results The sensitivity and specificity of ICDC for AIP were 98.4% (63/64) and 100% (90/90), respectively. The sensitivities and specificities of ductal imaging, serology, other organ involvement, and pancreatic histology were 74.1%, 89.1%, 53.1%, and 26.1% and 94.7%, 94.5%, 100%, and 100%, respectively. On the other hand, the sensitivities and specificities of JPS2011 for AIP were 84.4% (54/64) and 100% (90/90), respectively. The condition of all the 10 patients who were deniable or possible under the JPS2011 could be diagnosed as definitive AIP under the ICDC. The sensitivities and specificities of Japanese criteria 2006, Asian Diagnostic Criteria, and HISORt criteria were 80.6%, 84.4%, and 92.2% and 95.8%, 87.8%, and 100%, respectively. Conclusions The sensitivity and specificity of ICDC are higher than those of previous criteria. The JPS2011 is easy to handle for general practice, and specificity is very high. However, the sensitivity of JPS2011 is lower than that of ICDC, and improvement of sensitivity is to be hoped in the future.

Predictive factors for positive diagnosis of malignant biliary strictures by transpapillary brush cytology and forceps biopsy

The diagnostic yields of endoscopic transpapillary brush cytology and forceps biopsies for malignant biliary strictures (MBS) remain unclear and predictive factors for diagnosis have not been established. We aimed to clarify the diagnostic yields of both methods and the predictive factors

Stent under-expansion on the procedure day, a predictive factor for poor oral intake after metallic stenting for gastric outlet obstruction.

Self‐expandable metallic stents (SEMS) have been widely accepted as palliation therapy for malignant gastric outlet obstruction (GOO). However, the factors predictive of poor oral intake after SEMS placement have not been elucidated sufficiently. We aimed to clarify both the patient and stent‐related predictive factors.

New concept of traction force applied to biliary self-expandable metallic stents

BACKGROUND AND STUDY AIMS Various mechanical properties of self-expandable metallic stents (SEMSs) have been reported. They can be classified into the device behavior during and after deployment. While there have been several reports on the latter, information on the former is insufficient. During deployment, the position is maintained by retracting the delivery catheter. We propose that this pulling force be called the traction force and that the magnitude of traction force is termed the traction momentum. The aim of this study was to measure these parameters in order to clarify the properties of SEMSs in terms of their deployment. MATERIAL AND METHODS The traction force, traction momentum, and shortening rate of 10 different SEMSs were measured. Traction force was measured using in-house equipment, and the shortening rate was determined by measuring the stents. RESULTS The shortening rate was closely related to the stent structure. The traction force varied between 1.5 N and 9.4 N, and the traction momentum was significantly elevated in covered and braided stents. A high traction force did not imply a high traction momentum. CONCLUSIONS A low or constant traction force and a minimal shortening rate significantly facilitated SEMS deployment to optimal positions. Traction force could be an important element for new ideal SEMS design.

Correlation between long-term outcome and steroid therapy in type 1 autoimmune pancreatitis: relapse, malignancy and side effect of steroid

Abstract Objectives. Autoimmune pancreatitis (AIP) responds well to corticosteroid therapy (CST), and CST is essential to induce remission. However, the correlation between long-term outcome and CST has not been evaluated. We aimed to clarify the correlation between long-term outcome of AIP and CST. Material and methods. We retrospectively evaluated relapse, risk of malignancy and side effects of CST by focusing on the correlation with CST in 84 patients with type 1 AIP. Results. The incidence of relapse was 23.8%. The frequency of relapse after CST administration was significantly lower in patients taking CST for >6 months than in those who did not (22% versus 67%; p = 0.036). The incidence of malignancy was 10.7%. The standardized incidence ratio of malignancy was 2.14 [95% confidence interval 0.74–3.54]. There were no significant correlations between development of malignancy and CST. The incidences of total and serious side effects due to CST were 75% and 19.1%, respectively. Relapse was the only significant independent predictive risk factor for serious side effects in a multivariate analysis (odds ratio 4.065; 95% confidence interval 1.125–14.706; p = 0.032). The cumulative dose of corticosteroid was significantly higher in patients with serious side effects than in those without (12,645 mg versus 7322 mg; p = 0.041). Conclusions. CST reduces relapse of AIP. However, CST causes serious side effects, particularly in relapsing patients. Alternative maintenance therapy to prevent relapse is needed.

8-mm versus 10-mm diameter self-expandable metallic stent in bilateral endoscopic stent-in-stent deployment for malignant hilar biliary obstruction

We aimed to clarify the clinical benefits of using 8‐mm versus 10‐mm diameter self‐expandable metallic stent (SEMS) in bilateral endoscopic stent‐in‐stent (SIS) deployment for malignant hilar biliary obstruction (MHBO).