Enhancer Reprogramming Promotes Pancreatic Cancer Metastasis.

Pancreatic ductal adenocarcinoma (PDA) is one of the most lethal human malignancies, owing in part to its propensity for metastasis. Here, we used an organoid culture system to investigate how transcription and the enhancer landscape become altered during discrete stages of disease progression in a PDA mouse model. This approach revealed that the metastatic transition is accompanied by massive and recurrent alterations in enhancer activity. We implicate the pioneer factor FOXA1 as a driver of enhancer activation in this system, a mechanism that renders PDA cells more invasive and less anchorage-dependent for growth in vitro, as well as more metastatic in vivo. In this context, FOXA1-dependent enhancer reprogramming activates a transcriptional program of embryonic foregut endoderm. Collectively, our study implicates enhancer reprogramming, FOXA1 upregulation, and a retrograde developmental transition in PDA metastasis.

A TEAD2-Driven Endothelial-Like Program Shapes Basal-Like Differentiation and Metastasis of Pancreatic Cancer.

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDA), with its highly metastatic propensity, is one of the most lethal subtypes of pancreatic cancer. Although recent large-scale transcriptomic studies have demonstrated that heterogeneous gene expressions play an essential role in determining molecular phenotypes of PDA, biological cues for and consequences of distinct transcriptional programs remain unclear. METHODS: We developed an experimental model that enforces the transition of PDA cells toward a basal-like subtype. We combined epigenome and transcriptome analyses with extensive in vitro and in vivo evaluations of tumorigenicity to demonstrate the validity of basal-like subtype differentiation in association with endothelial-like enhancer landscapes via TEA domain transcription factor 2 (TEAD2). Finally, we used loss-of-function experiments to investigate the importance of TEAD2 in regulating reprogrammed enhancer landscape and metastasis in basal-like PDA cells. RESULTS: Aggressive characteristics of the basal-like subtype are faithfully recapitulated in vitro and in vivo, demonstrating the physiological relevance of our model. Further, we showed that basal-like subtype PDA cells acquire a TEAD2-dependent proangiogenic enhancer landscape. Genetic and pharmacologic inhibitions of TEAD2 in basal-like subtype PDA cells impair their proangiogenic phenotypes in vitro and cancer progression in vivo. Last, we identify CD109 as a critical TEAD2 downstream mediator that maintains constitutively activated JAK-STAT signaling in basal-like PDA cells and tumors. CONCLUSIONS: Our findings implicate a TEAD2-CD109-JAK/STAT axis in the basal-like differentiated pancreatic cancer cells and as a potential therapeutic vulnerability.

HNF1B-driven three-dimensional chromatin structure for molecular classification in pancreatic cancers.

The molecular subtypes of pancreatic cancer (PC), either classical/progenitor-like or basal/squamous-like, are currently a major topic of research because of their direct association with clinical outcomes. Some transcription factors (TFs) have been reported to be associated with these subtypes. However, the mechanisms by which these molecular signatures of PCs are established remain unknown. Epigenetic regulatory processes, supported by dynamic changes in the chromatin structure, are essential for transcriptional profiles. Previously, we reported the importance of open chromatin profiles in the biological features and transcriptional status of PCs. Here, we aimed to analyze the relationships between three-dimensional (3D) genome structures and the molecular subtypes of human PCs using Hi-C analysis. We observed a correlation of the specific elements of 3D genome modules, including compartments, topologically associating domains, and enhancer-promoter loops, with the expression of related genes. We focused on HNF1B, a TF that is implicated in the progenitor subtype. Forced expression of HNF1B in squamous-type PC organoids induced the upregulation and downregulation of genes associated with progenitor and squamous subtypes, respectively. Long-range genomic interactions induced by HNF1B were accompanied by compartment modulation and H3K27ac redistribution. We also found that these HNF1B-induced changes in subtype-related gene expression required an intrinsically disordered region, suggesting a possible involvement of phase separation in compartment modulation. Thus, mapping of 3D structural changes induced by TFs, such as HNF1B, may become a useful resource for further understanding the molecular features of PCs.

MNX1-HNF1B Axis Is Indispensable for Intraductal Papillary Mucinous Neoplasm Lineages.

BACKGROUND & AIMS: Chromatin architecture governs cell lineages by regulating the specific gene expression; however, its role in the diversity of cancer development remains unknown. Among pancreatic cancers, pancreatic ductal adenocarcinoma (PDAC) and intraductal papillary mucinous neoplasms (IPMN) with an associated invasive carcinoma (IPMNinv) arise from 2 distinct precursors, and their fundamental differences remain obscure. Here, we aimed to assess the difference of chromatin architecture regulating the transcriptional signatures or biological features in pancreatic cancers. METHODS: We established 28 human organoids from distinct subtypes of pancreatic tumors, including IPMN, IPMNinv, and PDAC. We performed exome sequencing (seq), RNA-seq, assay for transposase-accessible chromatin-seq, chromatin immunoprecipitation-seq, high-throughput chromosome conformation capture, and phenotypic analyses with short hairpin RNA or clustered regularly interspaced short palindromic repeats interference. RESULTS: Established organoids successfully reproduced the histology of primary tumors. IPMN and IPMNinv organoids harbored GNAS, RNF43, or KLF4 mutations and showed the distinct expression profiles compared with PDAC. Chromatin accessibility profiles revealed the gain of stomach-specific open regions in IPMN and the pattern of diverse gastrointestinal tissues in IPMNinv. In contrast, PDAC presented an impressive loss of accessible regions compared with normal pancreatic ducts. Transcription factor footprint analysis and functional assays identified that MNX1 and HNF1B were biologically indispensable for IPMN lineages. The upregulation of MNX1 was specifically marked in the human IPMN lineage tissues. The MNX1-HNF1B axis governed a set of genes, including MYC, SOX9, and OLFM4, which are known to be essential for gastrointestinal stem cells. High-throughput chromosome conformation capture analysis suggested the HNF1B target genes to be 3-dimensionally connected in the genome of IPMNinv. CONCLUSIONS: Our organoid analyses identified the MNX1-HNF1B axis to be biologically significant in IPMN lineages.

Axin2+ Peribiliary Glands in the Periampullary Region Generate Biliary Epithelial Stem Cells That Give Rise to Ampullary Carcinoma.

BACKGROUND & AIMS: Peribiliary glands (PBGs), clusters of epithelial cells residing in the submucosal compartment of extrahepatic bile ducts, have been suggested as biliary epithelial stem/progenitor cell niche; however, evidence to support this claim is limited because of a lack of PBG-specific markers. We therefore sought to identify PBG-specific markers to investigate the potential role of PBGs as stem/progenitor cell niches, as well as an origin of cancer. METHODS: We examined the expression pattern of the Wnt target gene Axin2 in extrahepatic bile ducts. We then applied lineage tracing to investigate whether Axin2-expressing cells from PBGs contribute to biliary regeneration and carcinogenesis using Axin2-CreERT mice. RESULTS: Wnt signaling activation, marked by Axin2, was limited to PBGs located in the periampullary region. Lineage tracing showed that Axin2-expressing periampullary PBG cells are capable of self-renewal and supplying new biliary epithelial cells (BECs) to the luminal surface. Additionally, the expression pattern of Axin2 and the mature ductal cell marker CK19 were mutually exclusive in periampullary region, and fate tracing of CK19+ luminal surface BECs showed gradual replacement by CK19- cells, further supporting the continuous replenishment of new BECs from PBGs to the luminal surface. We also found that Wnt signal enhancer R-spondin3 secreted from Myh11-expressing stromal cells, corresponding to human sphincter of Oddi, maintained the periampullary Wnt signal-activating niche. Notably, introduction of PTEN deletion into Axin2+ PBG cells, but not CK19+ luminal surface BECs, induced ampullary carcinoma whose development was suppressed by Wnt inhibitor. CONCLUSION: A specific cell population receiving Wnt-activating signal in periampullary PBGs functions as biliary epithelial stem/progenitor cells and also the cellular origin of ampullary carcinoma.

Blocking VCAM-1 inhibits pancreatic tumour progression and cancer-associated thrombosis/thromboembolism.

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is the deadliest cancer. Cancer-associated thrombosis/thromboembolism (CAT), frequently observed in PDAC, is known as a poor prognostic factor. Here, we investigated the underlying mechanisms between PDAC and CAT, and performed a trial of therapeutic approach for PDAC using a genetically engineered mouse model, PKF (Ptf1acre/+;LSL-KrasG12D/+;Tgfbr2flox/flox ). DESIGN: Presence of CAT in PKF mice was detected by systemic autopsy. Plasma cytokines were screened by cytokine antibody array. Murine and human plasma atrial natriuretic peptide (ANP) and soluble vascular cell adhesion molecule 1 (sVCAM-1) were determined by ELISA. Distribution of VCAM-1 in PKF mice and human autopsy samples was detected by immunohistochemistry. PKF mice were treated with anti-VCAM-1 antibody and the effects on survival, distribution of CAT and the tumour histology were analysed. RESULTS: We found spontaneous CAT with cardiomegaly in 68.4% PKF mice. Increase of plasma ANP and sVCAM-1 was observed in PKF mice and PDAC patients with CAT. VCAM-1 was detected in the activated endothelium and thrombi. Administration of anti-VCAM-1 antibody to PKF mice inhibited tumour growth, neutrophil/macrophage infiltration, tumour angiogenesis and progression of CAT; moreover, it dramatically extended survival (from 61 to 253 days, p<0.01). CONCLUSION: Blocking VCAM-1/sVCAM-1 might be a potent therapeutic approach for PDAC as well as CAT, which can contribute to the prognosis. Increase of plasma ANP and sVCAM-1 might be a diagnostic approach for CAT in PDAC.

Genetic reduction of cilium length by targeting intraflagellar transport 88 protein impedes kidney and liver cyst formation in mouse models of autosomal polycystic kidney disease.

Polycystin-1 (PC1) and -2 (PC2), products of the PKD1 and PKD2 genes, are mutated in autosomal dominant polycystic kidney disease (ADPKD). They localize to the primary cilia; however, their ciliary function is in dispute. Loss of either the primary cilia or PC1 or PC2 causes cyst formation. However, loss of both cilia and PC1 or PC2 inhibits cyst growth via an unknown pathway. To help define a pathway, we studied cilium length in human and mouse kidneys. We found cilia are elongated in kidneys from patients with ADPKD and from both Pkd1 and Pkd2 knockout mice. Cilia elongate following polycystin inactivation. The role of intraflagellar transport proteins in Pkd1-deficient mice is also unknown. We found that inactivation of Ift88 (a gene expressing a core component of intraflagellar transport) in Pkd1 knockout mice, as well as in a new Pkd2 knockout mouse, shortened the elongated cilia, impeded kidney and liver cystogenesis, and reduced cell proliferation. Multi-stage in vivo analysis of signaling pathways revealed ß-catenin activation as a prominent, early, and sustained event in disease onset and progression in Pkd2 single knockout but not in Pkd2.Ift88 double knockout mouse kidneys. Additionally, AMPK, mTOR and ERK pathways were altered in Pkd2 single knockout mice but only AMPK and mTOR pathway alteration were rescued in Pkd2.Ift88 double knockout mice. Thus, our findings advocate an essential role of polycystins in the structure and function of the primary cilia and implicate ß-catenin as a key inducer of cystogenesis downstream of the primary cilia. Our data suggest that modulating cilium length and/or its associated signaling events may offer novel therapeutic approaches for ADPKD.

Outcome of Long-term Maintenance Steroid Therapy Cessation in Patients With Autoimmune Pancreatitis: A Prospective Study.

OBJECTIVE: To predict the duration of steroid maintenance therapy required to achieve good prognosis in patients with autoimmune pancreatitis. PATIENTS AND METHODS: The study sample comprised 21 patients with autoimmune pancreatitis who met the following criteria: (1) they received steroid therapy (ST) for at least 3 years without clinical relapse; and (2) immunoglobulin (Ig) G<1600 mg/dL was observed in the past year with a prednisolone maintenance dose ≤5 mg. All patients could be diagnosed with international consensus diagnostic criteria. Patients were prospectively followed up after tapering and cessation of steroids. Clinical relapse was defined as the need to resume ST. Serological relapse was defined as having an IgG level of >1600 mg/dL. RESULTS: During the 43-month (range, 19 to 48 mo) follow-up period, clinical relapse occurred in 10 patients: pancreatic lesion in 4; coronary lesion in 2; submandibular lesion in 1; both pulmonary and renal lesions in 1; pulmonary, retroperitoneal, and submandibular lesions in 1; and bronchial asthma in 1. Serological relapse was observed in 12 patients. Although clinical and serological relapse occurred concomitantly in 3 patients, serological relapse preceded clinical relapse in 4 patients. Five patients experienced serological relapse alone, and no clinical or serological relapse occurred in 6 patients. According to Cox proportional hazard analysis, the duration of ST before tapering was a significant predictive parameter (hazard ratio, 0.969/month; 95% confidence interval, 0.940-0.998; P=0.038). CONCLUSIONS: ST cessation resulted in a high rate of clinical relapses, even in patients with long-term maintenance therapy. Therefore, it appears desirable to continue steroid maintenance therapy for a period >3 years to prevent relapse.

Risk factors for post-ERCP pancreatitis in wire-guided cannulation for therapeutic biliary ERCP.

BACKGROUND: Wire-guided cannulation (WGC) was reported to decrease post-ERCP pancreatitis (PEP), but risk factors for PEP in WGC are not fully elucidated. OBJECTIVE: To evaluate the incidence and risk factors of PEP in WGC. DESIGN: Single-center retrospective study. SETTING: Academic center. PATIENTS: A total of 800 consecutive patients with a native papilla. INTERVENTIONS: Biliary therapeutic ERCP by using WGC. MAIN OUTCOME MEASUREMENTS: The rate of PEP and its risk factors. RESULTS: Biliary cannulation was successful by using WGC alone in 70.5%, and the final cannulation rate was 96.1%. Unintentional guidewire insertion and contrast material injection into the pancreatic duct (PD) during cannulation occurred in 55.3% and 21.8%, respectively. The incidence of PEP was 9.5% (mild 5.6%, moderate 2.9%, severe 1.0%). Multivariate analysis revealed a common bile duct (CBD) diameter of <9 mm (odds ratio [OR] 2.03; P = .006) and unintentional guidewire insertion into the PD (OR 2.25; P = .014) as risk factors for PEP. PD opacification was not a risk factor for PEP (OR 1.15; P = .642), but the incremental increase of the PEP rate was seen in patients with CBDs <9 mm: 4.6% without any PD manipulation, 8.3% with contrast material alone, 16.9% with guidewire alone, and 22.1% with both contrast material and guidewire. LIMITATIONS: Retrospective design in a single center. CONCLUSION: Unintentional PD manipulation was not uncommon in WGC. Guidewire insertion into the PD and a small CBD were risk factors for PEP in biliary therapeutic ERCP with the use of WGC.

Loss of histone demethylase KDM6B enhances aggressiveness of pancreatic cancer through downregulation of C/EBPα.

Genetic mutations in pancreatic ductal adenocarcinoma (PDAC) with critical roles have been well examined. The recent discovery of alterations in genes encoding histone modifiers suggests their possible roles in the complexity of cancer development. We previously reported loss of heterozygosity of the KDM6B gene, which encodes a histone demethylase for trimethylated histone H3 lysine 27, a repressive chromatin mark, in PDAC cells. In this study, we demonstrated that loss of KDM6B enhanced aggressiveness of PDAC cells. KDM6B has been regarded as a tumor suppressor that mediates oncogenic KRAS-induced senescence. Consistently, KDM6B was highly expressed in pancreatic precancerous lesions (pancreatic intraepithelial neoplasms); then, the expression decreased as the malignant grade progressed. We found that knockdown of KDM6B in PDAC cells promoted tumor sphere formation and increased peritoneal dissemination and liver metastasis in vivo. Microarray and chromatin immunoprecipitation analysis implicated CEBPA for aggressiveness induced by KDM6B knockdown. CEBPA knockdown recapitulated the phenotypic change of PDAC cells after KDM6B knockdown, which was reversed by forced expression of C/EBPα. Moreover, similar protein expression patterns of KDM6B and C/EBPα in human PDAC emphasized their functional correlation. Notably, pharmacological inhibition of the H3K27 methylase EZH2 in PDAC cells inhibited tumor sphere formation along with the upregulation of CEBPA expression, and this effect was impaired in KDM6B knockdown cells, highlighting the role for KDM6B in the activation of CEBPA. Together, our results propose a significant role for the KDM6B-C/EBPα axis in the PDAC phenotype.

Disease-specific mortality among patients with intraductal papillary mucinous neoplasm of the pancreas.

BACKGROUND & AIMS: Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is associated with synchronous and metachronous pancreatic cancer. However, the risk factors for pancreatic cancer-specific mortality have not been determined. We evaluated disease-specific mortality among patients with IPMNs harboring high-risk stigmata. METHODS: We analyzed data from 243 patients diagnosed with IPMN, with indications for surgery according to the consensus criteria, at the University of Tokyo Hospital from 1995 to January 2011. By using optimal matching and propensity scores based on 16 characteristics, we matched patients who underwent surgery at diagnosis with those who did not undergo surgery. A competing risk analysis was used to assess the risk of pancreatic cancer-specific mortality. RESULTS: Fifty-nine patients underwent surgery after diagnosis and 184 did not. After adjustment with propensity scores, detection of a hypo-attenuating area by computed tomography, which indicates invasive carcinoma, was associated significantly with pancreatic cancer-specific mortality (adjusted hazard ratio, 16.75; 95% confidence interval, 2.72-103.3; P = .002). Cyst diameter, main pancreatic duct diameter, and the presence of a mural nodule were not associated significantly with pancreatic cancer-specific mortality. Surgical management was found to reduce pancreatic cancer-specific mortality, especially in patients with hypo-attenuating areas (P = .038). CONCLUSIONS: Detection of a hypo-attenuating area by computed tomography significantly increases the risk for pancreatic cancer-specific mortality among IPMN patients with consensus indications for surgery. Surgical resection significantly reduces this risk.

Detection of painless pancreatitis by computed tomography in patients with post-endoscopic retrograde cholangiopancreatography hyperamylasemia.

OBJECTIVES: Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis is diagnosed on the basis of pancreatic pain and hyperamylasemia. However, because the diagnosis of abdominal pain is not objective, there may be some cases of painless pancreatitis among patients with post-ERCP hyperamylasemia (PEH). We reviewed the computed tomography (CT) findings of PEH cases to determine the incidence of painless pancreatitis. METHODS: Between July, 2005 and December, 2011, CT was performed in 91 patients with hyperamylasemia 18 h after ERCP. We reviewed the CT findings and graded the severity of pancreatitis according to the Balthazar grading system. Grades C, D, and E were defined as pancreatitis. RESULTS: Thirty-four patients (37%) had pancreatitis according to the CT findings. There was a significant difference in the serum amylase levels between the positive- and negative-CT finding groups (1306 ± 833 vs. 786 ± 315 IU/L, respectively; p = 0.0012). Receiver operating characteristic curve analysis showed that the amylase cut-off value for discriminating between the 2 groups was 795 IU/L (6.36 times the upper normal limit). CONCLUSIONS: Thirty-seven percent of PEH patients had painless pancreatitis. CT is useful to determine pancreatitis in patients taking analgesics, steroids, or anti-immunological drugs and those with diabetes mellitus and 18-h serum amylase levels of >6 times the normal upper limit.

Short- and long-term outcomes of endoscopic papillary large balloon dilation with or without sphincterotomy for removal of large bile duct stones.

OBJECTIVE: Removal of large bile duct stones by endoscopic papillary large balloon dilation (EPLBD) with endoscopic sphincterotomy (EST) has been proven safe and effective. Little evidence supports the benefits of a preceding EST in reducing complications. Recent studies suggest that large bile duct stone removal by EPLBD alone may be safe and effective. MATERIAL AND METHODS: We removed large bile duct stones by EPLBD with EST from March 2008 to February 2010 and without EST from March 2010 to October 2011. Efficacy and safety of EPLBD with or without EST and late biliary complication outcomes were assessed. RESULTS: Forty-two patients (men/women, 27/15; mean age, 76 years) underwent EPLBD: 14 underwent EPLBD with EST and 28 underwent EPLBD without EST. The mean stone size was 14 mm (9-30 mm). Overall complete stone removal rate was 98%, with 83% achieved in 1 session. Complete duct clearance by EPLBD alone was achieved in 79%. Mechanical lithotripsy was required in 4 (10%) patients. Extracorporeal shock wave lithotripsy and electrohydraulic lithotripsy were required in 4 (10%) and 1 (2%) patients, respectively. Pancreatitis and perforation occurred in 2 (5%) and 1 (2%) patients, respectively. Patients treated by EPLBD with EST and by EPLBD alone did not differ in complication outcomes. Six (14%) patients had recurrent bile duct stones, with a significant correlation to dilated common bile duct (p = 0.0351). CONCLUSIONS: EPLBD is safe and effective in patients with large bile duct stones. Preceding EST may be unnecessary.

Metallic stent with high axial force as a risk factor for cholecystitis in distal malignant biliary obstruction.

BACKGROUND AND AIM: Tumor involvement to the orifice of cystic duct (OCD) is a risk factor for cholecystitis after self-expandable metallic stent (SEMS) placement, but its prevention is still difficult. We conducted this multicenter analysis to clarify a type of SEMS or a method to place SEMS which would decrease the incidence of cholecystitis after SEMS placement. METHODS: The incidence of cholecystitis was studied in consecutive patients receiving SEMS for distal malignant biliary obstruction in five tertiary care centers. Multiple logistic regression analysis was performed to evaluate risk factors for cholecystitis. RESULTS: A total of 376 patients who received SEMS placement for distal malignant biliary obstruction were analyzed. Tumor involvement to OCD was diagnosed in 25.3%. Overall incidence of cholecystitis was 6.9%. Cholecystitis was observed in 8.0% of 300 patients with covered SEMS, 16.8% of 95 patients with tumor involvement to OCD, 10.8% of 234 patients with SEMS of high axial force (AF), and 12.0% of 158 patients with SEMS length ≤ 60 mm. In the multivariate analysis, tumor involvement to OCD (odds ratio [OR] 5.40, P < 0.001), SEMSs with high AF (OR 5.33, P = 0.002), and SEMS length ≤ 60 mm (OR 3.19, P = 0.010) are risk factors. Among patients with tumor involvement to OCD, the incidence of cholecystitis in SEMS with high and low AF was 25.0% and 5.0%, respectively. CONCLUSION: This study with an expanded cohort reconfirmed tumor involvement to OCD as a risk factor for cholecystitis after SEMS placement. SEMS with low AF might decrease cholecystitis.

Slow pull versus suction in endoscopic ultrasound-guided fine-needle aspiration of pancreatic solid masses.

BACKGROUND: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic masses is an established procedure for obtaining a pathological specimen. However, application of suction during EUS-FNA is still controversial and the efficacy of the slow-pull technique was recently reported for new core biopsy needles. AIM: The purpose of this study was to compare the suction and slow-pull techniques using regular FNA needles. METHODS: The diagnostic yield of the suction and slow-pull techniques was retrospectively studied for patients who underwent EUS-FNA for pancreatic solid lesions. RESULTS: A total of 367 passes (181 by suction and 186 by the slow-pull technique) were performed during 97 EUS-FNA procedures for 93 patients with pancreatic solid lesions. The slow-pull technique resulted in lower scores for cellularity (≥2 for 37.5 % vs. 76.7 %) but scores for contamination with blood were lower (≥2 for 25.0 % vs. 66.7 %) and sensitivity of diagnosis of malignancy was higher (90.0 % vs. 67.9 %) when a 25-gauge FNA needle was used. There were no significant differences between the two techniques when a 22-gauge needle was used. In multivariate analysis of 82 cases with malignancy, the slow-pull technique (odds ratio (OR) 1.92, P = 0.028), tumor size ≥25 mm (OR 4.64, P < 0.001), and tumor location in the body or tail (OR 2.82, P < 0.001) were associated with greater sensitivity. CONCLUSION: The slow-pull technique was associated with less contamination with blood and can potentially increase the diagnostic yield compared with the suction technique in EUS-FNA of pancreatic solid masses, especially with a 25-gauge FNA needle.

High single-session success rate of endoscopic bilateral stent-in-stent placement with modified large cell Niti-S stents for malignant hilar biliary obstruction.

BACKGROUND: Endoscopic bilateral self-expandable metallic stent (SEMS) placement in a stent-in-stent method for malignant hilar biliary obstruction is technically challenging. Technical difficulties in the initial placement and reinterventions for stent occlusion are disadvantages inherent to this stent-in-stent method. We previously reported the feasibility of Niti-S large cell D-type biliary stents (LCD). This multicenter prospective consecutive study evaluated the efficacy of bilateral SEMS placement using modified LCD with large and uniform cells, a slimmer delivery system and high radial force. PATIENTS AND METHODS: From July 2010 to June 2011, 26 consecutive patients with unresectable malignant hilar biliary obstruction underwent endoscopic bilateral placement of modified LCD in a stent-in-stent method at three tertiary hospitals. Ten patients had gallbladder cancer, eight had cholangiocarcinoma, four had lymph node metastasis, two had intrahepatic cholangiocarcinoma, and two had liver metastasis. RESULTS: Single-session and final technical success rate was 96% and 100%, respectively. Functional success rate was 89%. Stent occlusion occurred in 11 patients (42%) because of sludge (n = 7) or tumor ingrowth (n = 4). Endoscopic bilateral reintervention was technically easy and successful: six patients had stent clearance by balloon sweeping and five had plastic stent placement. According to Kaplan-Meier analysis, median survival and stent patency were 220 days and 157 days, respectively. CONCLUSIONS: Modified LCD achieved a high technical success rate both in the initial stent-in-stent placement and in bilateral reinterventions in patients with malignant hilar biliary obstruction.

A multicenter phase II trial of gemcitabine and candesartan combination therapy in patients with advanced pancreatic cancer: GECA2.

BACKGROUND: Our retrospective study and phase I trial of gemcitabine and candesartan combination therapy suggested the inhibition of renin-angiotensin system potentially has a role in the treatment of advanced pancreatic cancer. The aim of this multicenter phase II trial was to assess the efficacy and toxicity of gemcitabine and candesartan combination therapy for advanced pancreatic cancer. METHODS: Chemotherapy-naive patients with histologically or cytologically proven advanced pancreatic cancer were enrolled. Gemcitabine was administered at a dose of 1,000 mg/m(2) over 30 min on days 1, 8, and 15 and oral candesartan at a dose of 16 mg in normotensive patients, and 8 mg initially in hypertensive patients, with dose escalation to 16 mg allowed, from days 1 to 28, repeated every 4 weeks. RESULTS: A total of 35 patients with advanced pancreatic cancer were enrolled. Overall response rate and disease control rate were 11.4 % and 62.9 %. The median PFS and OS were 4.3 and 9.1 months with 1-year survival rate of 34.2 %. The median PFS was significantly longer in patients receiving 16 mg compared with 8 mg of candesartan (4.6 vs. 3.5 months, p=0.031). Major severe toxicities were neutropenia (23 %), leukopenia (17 %) and thrombocytopenia (11 %). Grade 2 hypotension was observed in 3 patients (9 %) and candesartan was discontinued in 2 patients due to hypotension. Conclusions In this multicenter phase 2 trial, gemcitabine and candesartan combination therapy was tolerable but failed to demonstrate activity against advanced pancreatic cancer. (UMIN CTR: UMIN000005580).

Diabetes is a useful diagnostic clue to improve the prognosis of pancreatic cancer.

BACKGROUND/OBJECTIVES: Diabetes mellitus (DM) is recognized as a risk factor for pancreatic cancer (PaC) and expected to be a clue for early diagnosis. However, it is still obscure whether a diagnostic strategy using DM as a clue can improve the prognosis or not. METHODS: We retrospectively reviewed 540 patients with PaC, and investigated the prognosis with regard to the reasons for diagnosis. We compared patients diagnosed by imaging studies performed when DM was newly diagnosed or deteriorated, and patients diagnosed by symptoms. RESULTS: The prevalence of DM in PaC patients was 45% (256/540) and did not differ between disease stages. More than half of DM in PaC patients (150/256) were new-onset (<2 years in duration). One hundred sixty one patients (30%) were asymptomatic at PaC diagnosis. There were 38 patients diagnosed in association with DM (by new-onset DM, 16; by aggravation of long-standing DM, 22). Asymptomatic patients had smaller primary tumor and were diagnosed at an earlier stage. The prognosis of PaC patients complicated with DM did not differ from that of patients without DM; however, patients had better prognosis if they were diagnosed in association with DM alone (median survival time, 20.2 months), compared with patients diagnosed by symptoms (10.2 months, P < 0.01). CONCLUSIONS: Our analysis revealed that patients diagnosed in association with DM had better survival than symptomatic patients. Given the high prevalence of DM in PaC patients, DM can be a useful diagnostic clue for screening and lead to improvement of prognosis in PaC patients.

Preliminary report on a new, fully covered, metal stent designed for the treatment of pancreatic fluid collections.

BACKGROUND: Endoscopic transluminal treatment of pancreatic fluid collections (PFC) has been reported as an effective alternative approach to surgical treatment. A wide, short stent with an anti-migration system has been developed. OBJECTIVE: To evaluate a newly developed, fully covered, self-expandable metal stent (FCSEMS) customized for cystogastrostomy. DESIGN: Retrospective case series. SETTING: Tertiary-care academic medical centers and affiliated hospitals. PATIENTS: Nine patients who underwent endoscopic treatment of PFCs (5 with pseudocysts and 4 with walled-off pancreatic necrosis). INTERVENTION: Stent deployment after endoscopic US-guided puncture. Irrigation and necrosectomy were performed at the discretion of the endoscopist. MAIN OUTCOME MEASUREMENTS: Technical and clinical success rate, complications, and removability. RESULTS: The FCSEMS was inserted successfully in all cases (9/9, 100%). Clinical success was achieved in 7 of 9 cases (77.8%). No early complications associated with the procedure were observed. Late complications were observed in 2 cases (bleeding and asymptomatic migration). The FCSEMS was removed without any complications in all 6 cases where it was attempted after the procedure had been completed (100%). LIMITATIONS: This was a retrospective evaluation of a small number of cases. The FCSEMS was always inserted via the transgastric route. Follow-up duration was short. CONCLUSION: The endoscopic approach that uses this new FCSEMS is feasible for the treatment of PFCs. However, further evaluation is required.

Results of the Tokyo trial of prevention of post-ERCP pancreatitis with risperidone-2: a multicenter, randomized, placebo-controlled, double-blind clinical trial.

BACKGROUND: Our previous study suggested that a combination of ulinastatin and risperidone reduced post-ERCP pancreatitis (PEP) compared with ulinastatin alone. OBJECTIVE: The aim of this study was to evaluate the efficacy of risperidone alone for prevention of PEP. DESIGN: A multicenter, randomized, placebo-controlled, double-blind clinical trial. SETTING: Two academic hospitals and 5 referral hospitals in Tokyo and Saitama, Japan. PATIENTS: Patients undergoing therapeutic or interventional-diagnostic ERCP. INTERVENTION: The patients were randomized to receive 2 mg of oral risperidone or oral placebo at 0.5 to 2 hours before ERCP. MAIN OUTCOME MEASUREMENTS: The primary endpoint was the incidence of PEP. Secondary endpoints were the incidence of hyperenzymemia and enzyme levels (amylase, pancreatic amylase, lipase). Risk factors for PEP were evaluated. RESULTS: We initially enrolled 500 patients in the study (250 in the risperidone group and 250 in the placebo group), but 17 (11 in the risperidone and 6 in the placebo group) were excluded after randomization. PEP developed in 24 patients (10.0%) in the risperidone group and 21 patients (8.6%) in the placebo group (P = .587). Serum amylase levels at 3 hours after ERCP were lower in the risperidone group (P = .007 in a single test of hypothesis, significance removed by Bonferroni correction for multiple testing). In multivariate analysis, a small papilla of Vater, total procedure time ≥40 minutes, and stenosis of the intrahepatic duct were significantly associated with PEP. LIMITATIONS: Multiplicity of study centers and a relatively wide time range of drug administration time. CONCLUSION: Risperidone did not show a benefit in prevention of PEP in this trial. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT000004592.).