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In construction industries, new construction materials are needed to overcome some problems associated with the use of conventional construction materials due to the change of environmental and social requirements. Accordingly, the requirements to be satisfied in the design of civil engineering structures are diversified. As a new construction material in the civil engineering industries, fiber reinforced polymeric plastic (FRP) has a superior corrosion resistance, high specific strength/stiffness, etc. Therefore, such properties can be used to mitigate the problems associated with the use of conventional construction materials. Nowadays, new types of bridge piers and marine piles are being studied for new construction. They are made of concrete filled fiber reinforced polymeric plastic tubes (CFFT). In this paper, a new type of FRP-concrete composite pile which is composed of reinforced concrete filled FRP tube (RCFFT) is proposed to improve compressive strength as well as flexural strength of an RCFFT. The load carrying capacity of proposed RCFFT is discussed based on the result of experimental and analytical investigations.

Background The conformability of uncovered self-expandable metal stents (SEMSs) plays an important role in maintaining stent patency. However, whether increased conformability can prolong the duration of SEMS patency remains to be proved. Objective The aim of this study was to examine the efficacy and complication rates of the Niti-D biliary uncovered metal stent (NDS), which is more conformable than the uncovered Wallstent. Design Nonrandomized, retrospective study. Setting Tertiary-care academic medical center. Patients From March 2005 to July 2007, 101 patients received an NDS (41 cases) or a Wallstent (60 cases) for malignant biliary obstruction. Interventions SEMS placement. Results Stent occlusion occurred in 11 patients (26.8%) with the NDS and 17 patients (28.3%) with the Wallstent. The median duration of stent patency tended to be longer for the NDS group (153 days) than for the Wallstent group (124 days); however, the difference was not statistically significant ( P = .204). The median duration of overall survival of patients was 160 days for the NDS and 148 days for the Wallstent. The subgroup analysis showed that 27 patients had hilar obstruction (NDS 13, Wallstent 14). The median duration of stent patency was 249 days for the NDS group and 76 days for the Wallstent group; this difference was statistically significant ( P = .006). The complications included pancreatitis in 3 NDS cases and 5 Wallstent cases. Limitation The absence of prospective randomized recruitment. Conclusion The results of this study showed no significant differences between the NDS and the Wallstent for the palliative endoscopic management of malignant biliary obstruction. There were no significant differences in patency, complication rates, and patient survival between the more conformable NDS and the conventional Wallstent. However, the NDS, which has good conformability, may be preferred for hilar obstruction.

(2009). Teaching English as a Global Language in Korea: Curriculum Rhetoric and Reality. Asian Englishes: Vol. 12, No. 1, pp. 124-129.

Ever since immersion was first introduced to ELT in Korea, a variety of English immersion programs have been developed and implemented. They include ‘English camp’ or ‘English village’, ‘Teaching English in English (TEE)’, 'Content-based English instruction (CBEI),' and a total immersion school. The purpose of this paper is to examine the development of these English immersion programs in terms of their current state, the characteristic features, and the major issues and challenges. It was suggested for a successful implementation of English immersion education in Korean ELT context that a general consensus should be made on the goal of teaching English in general and immersion education in particular. Developing additive, balanced bilingualism was suggested as a more desirable goal than focusing on L2 acquisition only. Proper teacher education focusing on teacher collaboration was also emphasized.

Endoscopic intervention is considered to be the primary treatment for biliary stricture after adult living donor liver transplantation (LDLT) with duct-to-duct biliary reconstruction. The aim of this study was to investigate the risk factors of biliary stricture and the clinical outcomes and predictors of failure after endoscopic retrograde cholangiography with balloon dilation (ERC-D). We enrolled 239 adult patients who underwent LDLT between 2000 and 2006. Sixty-eight patients (28.4%) developed biliary stricture. Twenty-nine patients with anastomotic biliary stricture were treated with ERC-D and stenting. We retrospectively analyzed the risk factors of biliary stricture and the clinical outcomes of ERC-D. The median follow-up period was 31 months. The risk factors of biliary stricture on multiple logistic regression analysis were a graft with multiple bile ducts, a previous history of bile leakage, and hepatic artery stenosis. The overall success rate of ERC-D was 64.5%. On simple logistic regression, the failure of primary ERC-D was associated with late biliary stricture over 24 weeks and more than 8 weeks between a 2-fold increase of serum alkaline phosphatase from the stable level and ERC-D, even though these were not statistically significant on multiple logistic regression. The relapse rate of stricture after successful ERC-D was 30%. The duration of stenting in the recurrence group was shorter than that in the nonrecurrence group (11.8 +/- 5.03 versus 29.0 +/- 11.6 weeks, P = 0.004). ERC-D is effective for the management of anastomotic biliary stricture. However, the failure rate of primary ERC-D may be high in patients with late onset and delayed diagnosis of biliary stricture. The recurrence seems to occur frequently in patients with a short duration of stenting.

Objectives Previous studies have shown that ulinastatin may be effective at preventing pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). However, routine administration of ulinastatin is unlikely to be cost-effective. So the aim of this prospective study was to evaluate the effectiveness of low-dose ulinastatin at preventing pancreatitis in patients at high risk of post-ERCP pancreatitis. Methods A total of 227 patients (mean age, 63 years; 54% men) were randomized to receive placebo (n = 108) or active drug (n = 119) immediately after ERCP and received active drug (100,000 U of ulinastatin) or placebo. Occurrence of post-ERCP pancreatitis and hyperamylasemia were compared between the 2 groups. Results The overall incidence of pancreatitis was 6.2%, and no significant differences were observed between placebo- and ulinastatin-treated patients in terms of the frequencies of pancreatitis (5.6% vs 6.7%), abdominal pain, or hyperamylasemia. Pancreatic duct acinarization, papillectomy of ampulla of Vater adenoma, difficult cannulation, and female sex were identified as risk factors for pancreatitis in univariate analysis. Conclusions Low-dose prophylactic treatment with ulinastatin immediately after ERCP did not show a beneficial influence on the incidence of post-ERCP pancreatitis and hyperamylasemia in high-risk patients.

Gallbladder (GB) polyps are commonly encountered in clinical practice, and are found more frequently as the number of medical screening examinations increases. The aim of this study was to determine optimal practice guideline for surgical treatment and follow-up of GB polyps.Data from healthy subjects of Seoul National University Hospital (SNUH) Health Care System of Gangnam Center were used to investigate the true prevalence of GB polyps. We also enrolled 689 patients with GB polyps diagnosed at SNUH from May 1(st), 1988 to April 30(th), 2006.The GB polyp prevalence was 6.1% (7.1% in males and 4.8% in females). The median follow-up duration in the 689 study patients was 60 months, and 139 (20%) of them had polyps/=10 mm in size. Twenty-five of the 180 patients who underwent cholecystectomy had adenocarcinomas. The chi(2) test was used to identify which of the following were risk factors of malignancy: age, sex, symptoms, size, rate of growth, multiplicity, accompanying stones, and shape. Age (/=57 years), presence of symptoms, size (/=10 mm), and shape (sessile) were found to be statistically significant risk factors by univariate analysis. However, multivariate analysis identified only age (/=57 years) and size (/=10 mm) as independent predictors of malignancy.The present study shows that GB polyps/=10 mm in size in patients aged/=57 years are the independent factors predicting malignancy of the GB.

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is reported to have a high prevalence of extrapancreatic malignancy (EPM). The aims of this study were to evaluate the prevalence and associated factors of EPMs in IPMN patients and to compare these data with those of non-IPMN pancreatic cystic neoplasm (PCN) patients. The study included 385 PCN patients (210 IPMNs and 175 non-IPMNs) diagnosed from 1993 to 2007. PCN types, presence of EPMs, chronological relation of EPMs to PCN diagnosis, and their clinicopathological parameters were analyzed. The prevalence of EPM was 33.8% for IPMNs and 12.0% for non-IPMN PCNs (P

We undertook an evaluation of the clinical outcomes of endoscopic cholangioplasty (ECP) and percutaneous cholangioplasty (PCP) for biliary strictures after liver transplantation. We compared success rates of intervention, patency after successful intervention and procedure-related morbidities in 79 patients with anastomotic stricture (n = 54) or non-anastomotic stricture (n = 25). Twenty-five ECP and 61 PCP procedures were performed; seven PCP procedures were consecutively performed after failure of ECP. Fifty-one (64.6%) patients were successfully treated by cholangioplasty. Successful intervention rates (60.0% in ECP vs. 59.3% in PCP, p = 1.00) and patencies after successful intervention (44.8 +/- 7.4 months in ECP vs. 41.9 +/- 3.4 months in PCP, p = 0.47) were no different for the two techniques. However, the number of intervention sessions for PCP (7.2 +/- 0.6) was higher than for ECP (2.9 +/- 0.6) (p < 0.01). Multivariate analysis showed that only an anastomotic stricture was found to be related with a longer patency with an estimated odds ratio of 5.74 (p = 0.04) and had a tendency to be associated with successful intervention with an estimated odds ratio of 3.12 (p = 0.07) irrespective of techniques. Endoscopic access should be the preferred first approach in patients with biliary stricture after liver transplantation irrespective of the type of stricture, in view of its less invasive nature and patient convenience.

Apigenin is a dietary flavonoid possessing therapeutic potential against cancers. This study was designed to investigate whether combination therapy with gemcitabine and apigenin enhanced anti-tumor efficacy in pancreatic cancer. In vitro, the combination treatment resulted in more growth inhibition and apoptosis through the down-regulation of NF-kappa B activity with suppression of Akt activation in pancreatic cancer cell lines (MiaPaca-2, AsPC-1). In vivo, the combination therapy augmented tumor growth inhibition through the down-regulation of NF-kappa B activity with the suppression of Akt in tumor tissue. The combination of gemcitabine and apigenin enhanced anti-tumor efficacy through Akt and NF-kappa B activity suppression and apoptosis induction.

Background It has not been established whether endoscopic sphincterotomy (ES) prevents subsequent cholangitis in patients with cholangitis and with a common bile duct (CBD) stone not documented by ERCP. Objective The aim of this study was to investigate the role of ES on the recurrence of cholangitis in patients with a high probability of having a CBD stone, not demonstrated by ERCP. Design and Patients A total of 117 patients who were diagnosed as having cholangitis and a high probability of a CBD stone, not detected by ERCP, were retrospectively reviewed. Cumulative recurrence rates of cholangitis were compared for treatments with and without ES. Setting Multicenter, retrospective study. Interventions ES. Main Outcome Measurements Cumulative recurrence of cholangitis after ERCP. Results Eighty-three patients underwent ES (ES group) and 34 patients did not (non-ES group). No statistically significant differences between the 2 groups were evident in terms of demographic factors or laboratory findings. The mean (standard deviation) follow-up was 22.1 ± 17.2 months (range 3-66 months) in the ES group and 23.3 ± 14.9 months (range 6-84 months) in the non-ES group ( P = .72). The cumulative rates of cholangitis were 6.3% (4.8% vs 9.9%) at 1 year, 15.6% (9.2% vs 29.3%) at 3 years, and 19.5% (9.2% vs 52.9%) at 5 years for ES vs non-ES groups, respectively ( P = .04). By multivariate analysis, ES reduced cholangitis recurrence, with a hazard ratio of 0.305 (95% CI 0.095-0.975, P = .045). Limitations Retrospective study. Conclusions ES reduced further episodes of cholangitis in patients with an episode of cholangitis and a high probability of choledocholithiasis, despite the lack of a CBD stone seen on ERCP.

The aim of this study was to evaluate the prognostic significance of clinical and laboratory variables, and to investigate survival benefits for different treatment modalities in unresectable pancreatic cancer.The majority of pancreatic cancers are found to be unresectable. Therefore, estimations of prognosis and decisions of treatment modalities are important in optimizing the various aspects of care.Three hundred and forty unresectable locally advanced, or metastatic pancreatic cancer patients were enrolled from January 1998 to January 2005 at the Seoul National University Hospital.One hundred and five patients received chemotherapy only and 59 patients received concurrent chemoradiotherapy (CCRT). Age, performance status, tumor location, initial CA 19-9 level, American Joint Committee on Cancer stage, and treatment modality (supportive care only, chemotherapy, vs. CCRT) were found to have prognostic significance for overall survival (OS) by univariate analysis, whereas initial CA 19-9 level, stage, and treatment modality were identified as independent prognostic factors by multivariate analysis. In subgroup analysis, stage III patients treated by CCRT (median OS, 10.4 mo) or chemotherapy alone (11.3 mo) showed survival benefit over supportive care (6.4 mo), and stage IV patients treated by chemotherapy alone (6.4 mo) showed survival benefit over supportive care (3.1 mo).Initial CA 19-9, American Joint Committee on Cancer stage, and treatment modality were independent prognostic factors of OS, and the patients who received chemotherapy or CCRT showed better survival than those who received supportive care only.

Objectives Invasive intraductal papillary mucinous neoplasm (IPMN) of the pancreas is often considered to have a better prognosis than pancreatic ductal adenocarcinoma. The aim of this study was to evaluate and compare the prognosis and clinicopathologic features between 2 groups. Methods Clinicopathologic features and long-term outcome of 32 patients with invasive IPMN were retrospectively evaluated and compared with those of 332 patients with pancreatic ductal adenocarcinoma. Results Asymptomatic patients were more frequently observed in the group of invasive IPMN than ductal adenocarcinoma (28% vs 11%, P = 0.013). The distribution of stages of invasive IPMN was as follows: stage I (n = 10, 31%), II (n = 8, 25%), III (n = 3, 9%), and IV (n = 11, 34%). Among 19 patients who underwent resection for invasive IPMN, 10 (53%), 1 (5%), 1 (5%), and 2 (11%) had T1 stage tumors and tumor with lymph node metastasis, lymphatic, and perineural invasions, respectively, which were significantly infrequently observed compared with those with ductal adenocarcinoma. The 5-year survival rate of invasive IPMN was 33.9% compared with 9% of ductal adenocarcinoma (P = 0.011). The difference in the mean survival rates between invasive IPMN and ductal adenocarcinoma in patients without metastasis was also significant but not in patients with metastasis. During the median follow-up period of 18.4 months, 3 patients (16%) had a recurrence after resection for invasive IPMN. Conclusions Both the less aggressive pathological factors concerned with tumor invasiveness and early diagnosis of invasive IPMN contribute to higher survival rates of invasive IPMN than ductal adenocarcinoma. However, the prognosis of metastatic invasive IPMN is as poor as that of ductal adenocarcinoma.

We conducted this study to evaluate the efficacy of nonsurgical treatment for patients with infected pancreatic necrosis (IPN).Among 224 patients with acute pancreatitis from 2000 to 2004, there were 31 patients diagnosed as having IPN complication. The diagnostic criteria for IPN were either a positive culture or free gas in the pancreas of patients with acute pancreatic necrosis. Nonsurgical management including percutaneous drainage or endoscopic drainage (ED) followed by vigorous irrigation was initially attempted in all patients. Surgery was planned only when there was no clinical improvement after the initial nonsurgical treatment.Percutaneous drainage or ED was performed in 18 and 5 patients, respectively. Eight patients received antibiotics only. Four patients (12.9%) (3 from percutaneous drainage group and 1 from ED group) required surgery. Sepsis or fistula developed in 32% and 6% of patients, respectively, and was managed successfully. One patient (3.2%) died as a result of rapidly progressing multiorgan failure. The mean duration of hospitalization was 37 days. During the follow-up period, 7 patients were readmitted because of fever; they were managed by reposition of the drainage tube.Intensive nonsurgical treatment is very effective and safe and should be considered as an initial treatment modality for patients with IPN.

Endoscopic mechanical lithotripsy is frequently used to overcome the difficulties of removing large bile duct stones endoscopically. The aim of this study was to identify predictors of endoscopic mechanical lithotripsy failure.One hundred and thirty-four patients who underwent mechanical lithotripsy for difficult choledocholithiasis were evaluated retrospectively. Predictive factors of outcome and procedure-related complications were analyzed. The clinical outcomes of subsequent management were also evaluated in cases of unsuccessful endoscopic mechanical lithotripsy.Endoscopic mechanical lithotripsy was successful in 102 patients (76.1%). Stone impaction, size (or=30 mm), and the stone size to bile duct diameter ratio (1.0) were significant predictors of endoscopic mechanical lithotripsy failure, with estimated odds ratios of 17.83, 4.32 and 5.47, respectively. There was no difference in complication rates between the successful and failed mechanical lithotripsy groups. When mechanical lithotripsy failed, all patients were successfully treated using various modalities, including surgery, without mortality.An impacted stone, stone size (or=30 mm) and stone size to bile duct diameter ratio (1.0) were predictors of failure of endoscopic mechanical lithotripsy for a difficult bile duct stone. Alternative approaches should be considered in patients with predictors of unsuccessful endoscopic mechanical lithotripsy in order to avoid wasting time and resources.

This study aimed to evaluate the accuracy of endoscopic ultrasound (EUS) and cross-sectional imaging including multidetector computed tomography (MDCT) or magnetic resonance imaging (MRI) as a preoperative diagnostic modality for the pancreatic cystic lesions.Three hundred eighteen patients with surgically proven pancreatic cystic lesions were enrolled as a study cohort from 1998 to 2011. Preoperative radiological, EUS, and final histopathologic diagnosis were correlated to measure several kinds of diagnostic performance.A total of 318 patients underwent preoperative MDCT, with additional imaging modalities such MRI and/or EUS in 215 (67.6%) and 108 (34.0%) patients, respectively. κ Values among the different modalities were as follows: MDCT versus pathology = 0.52 (P0.0001), MDCT + MRI versus pathology = 0.674 (P0.0001), and EUS versus pathology = 0.558 (P0.0001). The sensitivity and specificity in terms of ability to predict neoplastic cysts were as follows: MDCT, 83.1%/70.0%; MDCT + MRI, 94.7%/58.7%; and EUS, 88.5%/52.9%. The diagnostic accuracies of MDCT and MDCT + MRI were 61.4% (62/101) and 80.5% (173/215), respectively, and that of EUS was 70.4% (76/108).Magnetic resonance imaging as an additional diagnostic modality to MDCT increased the accuracy, sensitivity, and specificity, as well in terms of predicting neoplastic cysts.

Covered self-expandable metal stent (CSEMS) has the risk of obstruction of the cystic duct, and the main and branch pancreatic ducts due to strong radial force and covering material, which results in cholecystitis and pancreatitis. A flower-type covered self-expandable metal stent (F-CSEMS) having a five-petal-shaped design with side grooves was constructed to prevent the obstruction of the cystic duct orifice. This study investigated the value of the F-CSEMS in protection for cholecystitis in a pig model. Fourteen pigs randomly underwent endoscopic placement of either F-CSEMS or conventional CSEMS (C-CSEMS). The stent was placed across the cystic duct orifice to impede bile drainage from the gallbladder. Drainage was checked at 24, 48, 120 and 168 h after implantation. Blood was collected at baseline, on days 2 and 7 following implantation. The animals were killed for histologic evaluation on day 7. All stents were successfully inserted into bile duct without any procedure-related complications. At 48 h, the rate of contrast drainage from the gallbladder was higher in the F-CSEMS group than the C-CSEMS group without significant difference (71.4 vs. 28.6 % p = 0.28). C-CSEMS was associated with higher levels of C-reactive protein (35.2 vs. 20.5 µg/dl, p = 0.03) and histologic inflammatory scores of gallbladder (score 4 vs. 2; p = 0.03). The F-CSEMS appears safe and helpful to prevent cholecystitis without disturbance of bile flow in a pig model.

This paper presents the results of an experimental study on the seismic performance of reinforced concrete (RC) bridge piers wrapped with FRP at the lap-spliced region. It is well known that the FRP wrapping on the surface of concrete bridge pier can prevent concrete cover from spalling and it can reduce the slip displacement of lap-spliced longitudinal re-bars due to confinement. In order to develop the effective way of strengthening the concrete bridge pier with poor lap-spliced longitudinal re-bars, which is not designed under seismic design consideration, a series of pier test under seismic loading condition is conducted. As a result, FRP wrapped bridge pier under seismic loading exhibits ductile behavior with plastic deformation at lap-spliced region. Half-scaled six circular and nine square pier specimens were tested under uniform concentric axial compression and quasi-static lateral loading at the top of the pier. For the purpose of comparison, two piers without lap-splice and two piers with lap-splice were not wrapped with FRP and tested under same loading condition. Other experimental parameters were the height of FRP wrapping and the reinforcing method. The experimental results showed that the FRP wrapping could significantly increase ductility of piers with lap-spliced longitudinal re-bars at the potential plastic hinge region.

OBJECTIVES The aim of this study was to compare the survival benefits associated with gemcitabine chemotherapy and 5-fluorouracil (5-FU)-based concurrent chemoradiotherapy (CCRT) in locally advanced unresectable pancreatic cancer. METHODS One hundred and thirty-eight locally advanced unresectable pancreatic cancer patients were retrospectively enrolled from January 1995 to January 2005. All cases were histologically proven, and patients received gemcitabine chemotherapy, 5-FU-based CCRT, or supportive care at Seoul National University Hospital. RESULTS Median overall survival was 8.2 months. Twenty-six patients received gemcitabine chemotherapy, 56 patients 5-FU-based CCRT, and 56 patients supportive care. Weight loss and treatment modality were identified as independent prognostic factors by multivariate analysis. Patients in the 5-FU-based CCRT (overall survival, 10.4 months) and gemcitabine chemotherapy (11.3 months) groups showed survival benefit over those received supportive care (6.1 months, P < 0.0001). No grades 3 to 4 toxic adverse effects occurred in either treatment group and no statistical significant survival difference was found between gemcitabine chemotherapy and 5-FU-based CCRT (P = 0.5). CONCLUSIONS Patients with locally advanced pancreatic cancer who received gemcitabine chemotherapy or 5-FU-based CCRT showed better survival than those who received supportive care only. Gemcitabine chemotherapy and 5-FU-based CCRT showed similar survival advantages.

AIM: To identify the risk factors for organ failure (OF) in cholangitis with bacteriobilia. METHODS: This study included 182 patients with acute cholangitis who underwent percutaneous transhepatic biliary drainage between January 2005 and April 2013. We conducted a retrospective analysis of comprehensive clinical and laboratory data. RESULTS: There were 24 cases (13.2%) of OF and five deaths (2.7%). Bile culture was positive for microbial growth in 130 out of 138 (94.2%) patients. In multivariate analysis of 130 patients with positive bile cultures, significant predictive factors for OF were the presence of extended-spectrum beta-lactamase (ESBL) organisms in blood cultures, pre-existing renal dysfunction, and choledocholithiasis as an etiology, with odds ratios of 15.376, 6.319, and 3.573, respectively. We developed a scoring system with a regression coefficient of each significant variable. The OF score was calculated using the following equation: (2.7 × ESBL organisms in blood cultures) + (1.8 × pre-existing renal dysfunction) + (1.3 × choledocholithiasis). This scoring system for predicting OF was highly specific (99.1%) and had a positive predictive value of 86.2%. CONCLUSION: ESBL organisms in blood cultures, pre-existing renal dysfunction, and choledocholithiasis are risk factors for OF in cholangitis with bacteriobilia. The OF scoring system may aid clinicians to identify a poor prognosis group.

Background & Aims: Next-generation sequencing (NGS) that enables the analyses of massively parallel sequences of DNA can advance the understanding of the underlying molecular pathophysiologies of cancer. Such recent genomic analyses have revealed a complex mutational landscape for PDACs. The aims of this study were to investigate the genomic profile to predict the chemotherapy response in unresectable PDACs. Methods: The total of 80 pathologically confirmed PDACs were enrolled and genomic DNA was extracted and quality control metrics of DNA analytes were measured. The specimens that passed a quality control test underwent targeted deep sequencing using a customized cancer panel (CancerSCAN) enriched in the exons of 83 genes. Results: Clinical prognostic factors associated with survival in PDAC were gender, tumor mass size, stage and chemotherapy response rate. (P=0.078, 0.009, 0.052 and Conclusion: Targeted sequencing using EUS-FNA specimens in PDAC showed excellent compatibilities to analyze genomic profiles of PDACs. Furthermore, novel genes associated with survival, metastasis and chemotherapy response in PDAC were identified. Citation Format: Joo Kyung Park, Kwang Hyuck Lee, Donghyun Park, Woong-Yang Park, Dae-Soon Son, Jong Kyun Lee, Kyu Taek Lee. Detection of genetic alterations to predict the chemotherapeutic responses in unresectable pancreatic ductal adenocarcinomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 423. doi:10.1158/1538-7445.AM2017-423

The role of three-dimensional (3D) printing has expanded in diverse areas in medicine. As plastic surgery needs to fulfill the different demands from diverse individuals, the applications of tailored 3D printing will become indispensable. In this study, we evaluated the feasibility of using 3D-printed polycaprolactone (PCL) scaffold seeded with fibrin/chondrocytes as a new dorsal augmentation material for rhinoplasty. The construct was surgically implanted on the nasal dorsum in the subperiosteal plane of six rabbits. The implants were harvested 4 and 12 weeks after implantation and evaluated by gross morphological assessment, radiographic imaging, and histologic examination. The initial shape of the implant was unchanged in all cases, and no definite post-operative complications were seen over the 3-month period. Radiologic evaluation confirmed that implants remained in the initial location without migration or extrusion. Histologic evaluations showed that the scaffold architectures were maintained with minimal inflammatory reactions; however, expected neo-chondrogenesis was not definite in the constructs. A new PCL scaffold designed by 3D printing method seeded with fibrin/chondrocytes can be a biocompatible augmentation material in rhinoplasty in the future.

Like in many other Asian countries, English has been taught throughout the history of Korean ELT as a foreign language whose norm and standard are untouchable and its mastery does not seem to be achievable for many Korean learners of English, if not for all. However, in accordance with globalization and the emergence of English as an international language, the 2008 Revised Korea’s National Curriculum defined English as an international language and the goal of teaching English now is to help Korean learners of English to become intercultural speakers of English. This was to bring a paradigm shift into overall Korean ELT culture and context and it did to some extent, having made changes and development in ELT goals and objectives, instructional methodology, testing and evaluation, and most of all, teachers’ and learners’ attitudes towards English language and its use. There still seems to be, however, a large gap between the curriculum rhetoric and the reality inside and outside the English classroom. Based on the results of literature review and analysis, this chapter will reflect the past and current ELT in Korea and project its future, addressing major issues, concerns, and resolutions in regard to teaching and learning of EIL in Korean culture and context. Discussions will be made in three parts: First, ELT policy and curriculum; Second, instruction and material; Third, Korean learners’ and teachers’ perceptions and attitudes towards EIL. The educational implications and suggestions will be also made in order to realize teaching EIL in Korean context more effectively and successfully.

Background Tissue-engineered heart valve leaflets are a promising way to overcome the inherent limitations of current prosthetic valves. The aim of this study was to compare the biological responses of an autologous cell seeded scaffold and an acellular scaffold implanted in the pulmonary valve leaflet in the same animal. Methods Myofibroblasts and endothelial cells were isolated and cultured from an ovine artery. A synthetic biodegradable scaffold consisting of polyglycolic acid and polylactic acid was initially seeded with the myofibroblasts, then coated with endothelial cells. Cells were seeded using a medium containing collagen and cultured. A tissue-engineered construct and a plain scaffold were implanted as double pulmonary valve leaflet replacement in the same animal in an ovine model (n=3). Additionally, the tissue-engineered construct (n=2) and the plain scaffold (n=2) were implanted as single valve leaflet replacements for long-term analysis. After sacrifice, the implanted valve leaflet tissues were retrieved, analyzed visually and using light microscopy. Results Three animals that underwent replacement of two valve leaflets with a tissue-engineered construct and a plain scaffold, survived only a short-time (12, 24, 36 hours). The death was attributed to heart failure caused by severe pulmonary insufficiency. Animals that underwent single valve leaflet replacement survived longer and were electively sacrificed at 6 and 9 weeks after operation. The analysis of the leaflets from the short-term survivors showed that the tissue-engineered constructs contained less fibrins and protein exudates than the plain scaffold. In contrast, leaflets obtained from animals surviving 6 and 9 weeks showed similar well organized granulation tissues in the tissue-engineered constructs and the plain scaffolds. Conclusion This animal experiment demonstrates that in the early phase of implantation, the tissue-engineered construct shows a better biological response in terms of antithrombogenicity than the plain scaffold, although both of them have similar results in the later reparative phase.

Although incidental pancreatic cystic neoplasms are being diagnosed with increasing frequency, little is known about the accurate prevalence of pancreatic cysts in the general population. The aims of this study were to evaluate the crude prevalence rate of pancreatic cystic neoplasms in asymptomatic healthy adults, and calculate the age- and sex-adjusted nationwide prevalence rate.A total of 21,745 asymptomatic individuals who underwent abdominal computed tomography (CT) as a health screening examination were enrolled between 2003 and 2013 at the Seoul National University Hospital Healthcare System Gangnam Center. Nationwide population data of 2010 were collected from the National Statistical Office, Korea.Incidental pancreatic cystic neoplasms were found in 457 individuals whose mean age was 58.7 years. The types of neoplasms were reviewed by 2 separate designated radiologists and the final diagnosis was made as follows: intraductal papillary mucinous neoplasm: 376 (82%), serous cystic neoplasm: 19 (4%), mucinous cystic neoplasm: 7 (2%), and indeterminate cysts: 55 (12%). Eight cases underwent operation. The crude prevalence rate was 2.1% and the age- and sex-adjusted expected nationwide prevalence was 2.2%. The prevalence increased with age.Here, we reported the first large-scale study among the healthy population to find out the prevalence rate of pancreatic cystic neoplasms; the age- and sex-adjusted prevalence was 2.2%, and increased with age. Further investigations regarding the clinical implications of incidental pancreatic neoplasms are necessary.

The effects of diabetes mellitus (DM) on sensitivity of fluorine-18 fluorodeoxyglucose positron emission tomography coupled with computed tomography ((18)F-FDG PET/CT) for diagnosing pancreatic ductal adenocarcinomas (PDACs) is not well known. This study was aimed to evaluate the effects of DM on the validity of (18)F-FDG PET/CT in PDAC.A total of 173 patients with PDACs who underwent (18)F-FDG PET/CT were enrolled (75 in the DM group and 98 in the non-DM group). The maximum standardized uptake values (SUVsmax) were compared.The mean SUVmax was significantly lower in the DM group than in the non-DM group (4.403 vs 5.998, P = .001). The sensitivity of SUVmax (cut-off value 4.0) was significantly lower in the DM group than in the non-DM group (49.3% vs 75.5%, P.001) and also lower in normoglycemic DM patients (n = 24) than in non-DM patients (54.2% vs 75.5%, P = .038).DM contributes to a lower SUVmax of (18)F-FDG PET/CT in patients with PDACs.

To investigate the prognostic factors determining the success rate of non-surgical treatment in the management of post-operative bile duct injuries (BDIs).The study patients were enrolled from the pancreatobiliary units of a tertiary teaching hospital for the treatment of BDIs after hepatobiliary tract surgeries, excluding operations for liver transplantation and malignancies, from January 1999 to August 2010. A total of 5167 patients underwent operations, and 77 patients had BDIs following surgery. The primary end point was the treatment success rate according to different types of BDIs sustained using endoscopic or percutaneous hepatic approaches. The type of BDI was defined using one of the following diagnostic tools: endoscopic retrograde cholangiography, percutaneous transhepatic cholangiography, computed tomography scan, and magnetic resonance cholangiography. Patients with a final diagnosis of BDI underwent endoscopic and/or percutaneous interventions for the treatment of bile leak and/or stricture if clinically indicated. Patient consent was obtained, and study approval was granted by the Institutional Review Board in accordance with the legal regulations of the Human Clinical Research Center at the Seoul National University Hospital in Seoul, South Korea.A total of 77 patients were enrolled in the study. They were divided into three groups according to type of BDI. Among them, 55 patients (71%) underwent cholecystectomy. Thirty-six patients (47%) had bile leak only (type 1), 31 patients had biliary stricture only (type 2), and 10 patients had both bile leak and biliary stricture (type 3). Their initial treatment modalities were non-surgical. The success rate of non-surgical treatment in each group was as follows: BDI type 1: 94%; type 2: 71%; and type 3: 30%. Clinical parameters such as demographic factors, primary disease, operation method, type of operation, non-surgical treatment modalities, endoscopic procedure steps, type of BDI, time to diagnosis and treatment duration were evaluated to evaluate the prognostic factors affecting the success rate. The type of BDI was a statistically significant prognostic factor in determining the success rate of non-surgical treatment. In addition, a shorter time to diagnosis of BDI after the operation correlated significantly with higher success rates in the treatment of type 1 BDIs.Endoscopic or percutaneous hepatic approaches can be used as an initial treatment in type 1 and 2 BDIs. However, surgical intervention is a treatment of choice in type 3 BDI.

AIM: To identify clinical and pathological differences between serum immunoglobulin G4 (IgG4)-positive (SIP) and IgG4-negative (SIN) type 1 autoimmune pancreatitis (AIP) in South Korea. METHODS: AIP was diagnosed by the international consensus diagnostic criteria. The medical records and pathology were retrospectively reviewed and IgG4-positive cells were counted in a high power field (HPF). Type I AIP was defined as a high serum level of IgG4 or histological finding. SIN type 1 AIP was defined as a histological evidence of type 1 AIP and a normal serum IgG4 level. The clinical and pathological findings were compared between the two groups. The analysis was performed using Student’s t test, Fischer’s exact test and Mann-Whitney’s U test. A P value of < 0.05 was considered statistically significant. As repeated comparison was made, P values of less than 5% (P < 0.05) were considered significant. RESULTS: Twenty five patients with definite type 1 AIP (19 histologically and six serologically diagnosed cases) were enrolled. The mean tissue IgG4 concentrations were significantly higher in SIP than SIN group (40 cells per HPF vs 18 cells per HPF, P = 0.02). Among eight SIN patients, the tissue IgG4 concentrations were less than 15 cells per HPF in most of cases, except one. The sensitivity of serum IgG4 was 68% (17 SIP and eight SIN AIP). Other organ involvement was more frequently associated with SIP than SIN AIP (59% vs 26%, P = 0.016). However, the relapse rate and diffuse swelling of the pancreas were not associated with serum IgG4 level. The concentrations of IgG4-positive cells per HPF were higher in SIP than SIN AIP (40 vs 18, P = 0.02). CONCLUSION: The sensitivity of serum IgG4 was 68% in type 1 AIP. High serum IgG4 level was associated with other organ involvement and tissue IgG4 concentration but did not affect the relapse rate in type 1 AIP.

Propensity score indicates a probability of having a confounding factor. It is used to match each patient with the closest propensity score between two groups, which is known as propensity score matching. This study aimed to evaluate the gallstone-related biliary events, defined as biliary colic and acute cholecystitis between coronary artery disease (CAD) and non-CAD patients using propensity score matching.This retrospective cohort study evaluated 267 asymptomatic gallstone patients with CAD and 459 asymptomatic gallstone patients without CAD from March 2003 to December 2009 at two tertiary teaching hospitals in the Republic of Korea. After propensity score matching, total 378 patients, including 126 in study group (with CAD) and 252 in control group (without CAD), were evaluated.During a median follow-up of 47 months, overall gallstone-related biliary event rate was 33.5% in the study group and 27.5% in the control group. The 5-year cumulative rates were 25.3% versus 17.7% in gallstone-related biliary event and 10.9% versus 1.6% in acute cholecystitis (study versus control group). After propensity score adjustment, the risk of gallstone-related biliary events in the CAD patients significantly increased (hazard ratio 2.11, 95% confidence interval 1.14-3.90, P = 0.017 in matched patients).In patients with asymptomatic gallstones, the coexistence of CAD can increase the risk of gallstone-related biliary events, particularly acute cholecystitis. Therefore, gallstone patients with CAD should be carefully monitored, even if they are asymptomatic.

Overexpression of microRNA-21 (miR-21) indicates chemoresistance in pancreatic cancer. We evaluated the change of chemosensitivity to gemcitabine through the down-regulation of miR-21 in human pancreatic cancer cells (Panc-1).The efficacy of indole-3-carbinol (I3C) in suppressing miR-21 expression and its anticancer effect in combination with gemcitabine were investigated.Down-regulation of miR-21 by I3C was positively-correlated in a time- and dose-dependent manner. I3C and gemcitabine combination therapy increased cytotoxicity in Panc-1 cells. Transfection of miR-21 mimic abrogated I3C-induced sensitivity to gemcitabine. DNA fragmentation and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assays showed that pre-treatment with I3C enhanced apoptosis and this effect was attenuated by miR-21 transfection. The expression of programmed cell death-4 (PDCD4) was increased by I3C and reduced by miR-21 transfection.I3C would be effective for enhancing sensitivity of pancreatic cancer cells to gemcitabine via down-regulation of miR-21. Such enhanced chemosensitivity might be explained by the increased expression of PDCD4, which is a downstream target which miR-21 negatively regulates.

Next-generation sequencing (NGS) that enables the analyses of massively parallel sequences of DNA can advance the understanding of the underlying molecular pathophysiologies of cancer. Such recent genomic analyses have revealed a complex mutational landscape in surgical specimens of PDAC. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is used in the diagnosis of pancreatic cancer. Several genomic analyses using EUS-FNA in PDAC have been undertaken in a small number of patients. This study evaluated the feasibility of targeted NGS of specimens obtained using EUS-FNA to clarify genetic markers associated with the prognosis of pancreatic cancer. One hundred sixty six patients who underwent EUS-FNA with pathologically confirmed PDAC were included. Genomic DNA was extracted and quality control metrics of DNA analytes were measured. The specimens that passed a quality control test (N = 101, 61%) underwent NGS using a customized cancer panel (CancerSCAN) enriched in the exons of 83 genes. Clinical prognostic factors associated with survival in PDAC were age, performance status, CA 19-9 level, curative resection, chemotherapy, tumor mass size, tumor location, stage and metastasis site in univariate analysis (P = 0.020, Citation Format: Joo Kyung Park, Kwang Hyuk Lee, Jong Kyun Lee, Kyu Taek Lee, Woong-Yang Park, Dae-Soon Son. Targeted sequencing from endoscopic ultrasound-guided fine needle aspirates of pancreatic ductal adenocarcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 96.

Background Although dose tapering of tumour necrosis factor (TNF)-blockers in ankylosing spondylitis (AS) showed a comparable clinical efficacy with favourable safety and cost in some studies, there has been no investigation comparing the radiographic progression of patients with tapering regimen versus patients with standard-dose treatment. Objectives To investigate the impact of dose reduction of TNF-blockers on radiographic progression in the AS over 4 years Methods One hundred sixty five patients treated with etanercept or adalimumab were selected from single-centre, prospective observational cohort based on the availability of cervical and lumbar radiographs at baseline and after 2 and/or 4 years of the treatment. Radiographs were scored using modified Stokes AS spinal score (mSASSS) by two independent readers. Radiographic progression of patients treated with standard-dose (standard-dose group, n=49) was compared with that of patients who tapered the dosage during the TNF-blocker treatment (tapering group, n=116) using linear mixed models. Results Demographic and clinical factors at baseline between two groups were not significantly different except for higher initial BASDAI (7.1 vs. 6.3, p=0.003) in the standard-dose group. Baseline mSASSS (SD) of the standard-dose group and the tapering group were 17.3 (17.7) and 11.0 (16.0), respectively (p=0.059). At 2 years after the treatment, mean dose quotient (SD) of the tapering group was 0.59 (0.17) and time to first dose reduction (SD) was 36.6 (28.4) weeks. During the observation period, the rate of radiographic progression in the overall patients was 0.90 mSASSS unit/year. Rate of progression was significantly higher in patients with longer disease duration (≥10 years), elderly patients (≥40 years old), smokers, or patients with a hip involvement at baseline. Radiographic progression over 4 years between two treatment strategies was similar after the adjustment for baseline status. However, in the subgroup of patients who have syndesmophytes at baseline, it occurred significantly faster in the tapering group (1.30 mSASSS unit/year vs. 1.82 mSASSS unit/year, p=0.008) (figure). This result was concordant when radiographic progression was assessed by the development of new syndesmophytes (0.52/year vs. 0.73/year, p=0.047). Conclusions Dose tapering strategy of TNF-blockers is associated with more rapid radiographic progression in AS patients who have syndesmophytes at baseline. References Zavada J, et al. A tailored approach to reduce dose of anti-TNF drugs may be equally effective, but substantially less costly than standard dosing in patients with ankylosing spondylitis over 1 year: a propensity score-matched cohort study. Ann Rheum Dis 2016;75:96–102. Disclosure of Interest None declared

Background Interstitial lung disease (ILD) is associated with a significant morbidity and mortality in systemic sclerosis (SSc). Many studies have reported the association between human leukocyte antigen (HLA) alleles and increased risk of SSc, but the associated between ILD in SSc and HLA alleles remains unclear. Objectives The aim of this study was to investigate the association of HLA class I and HLA class II with ILD in Korean SSc cohort. Methods A total of 170 SSc patient (105 SSc patients with ILD and 65 SSc patients without ILD) were enrolled at Seoul National University Hospital from 1988 to 2014. Two hundred one healthy participants from Korean Marrow Donor Program (KMDP) were recruited as controls. Demographic information, clinical skin subset (limited vs. diffuse), SSc-specific autoantibodies (anti-topoisomerase I (ATA), anti-centromere (ACA), anti-ribonucleoprotein (RNP)), and internal organ involvement (ILD, pulmonary arterial hypertension, gastrointestinal, renal involvement) of the enrolled patients were characterized. ILD were diagnosed based on the findings of the chest computed tomography. HLA-A, -B, -C,-DQB1,-DRB1, and -DPB1 typing were performed PCR amplification with directly sequencing from extracted genomic DNA. Results HLA-B*52:01, C*12:02, DRB1*15:02, DPB1*09:01, and DPB1*13:01 alleles were more frequent in SSc patients with ILD than healthy controls. However, the frequencies of these genes did not differ between SSc patients with and without ILD (Table). ATA positive SSc was associated with HLA-B*52:01, C*12:02, DRB1*15:02, DPB1*09:01, and DPB1*13:01 alleles compared to ATA negative SSc and DPB1*09:01 showed the highest odds ratio for ATA (OR =23.08). Conclusions SSc patients with ILD have several specific HLA genes compared with healthy controls and the frequencies of these HLA genes were significantly higher in ATA-positive SSc as well. Therefore, ATA positivity and ILD are associated with ceratin HLA class I and II in SSc patients. References Zhou X, Lee JE, Arnett FC, Xiong M, Park MY, Yoo YK, et al. HLA-DPB1 and DPB2 are genetic loci for systemic sclerosis: a genome-wide association study in Koreans with replication in North Americans. Arthritis Rheum 2009;60:3807–14. Disclosure of Interest None declared

There is no doubt that urgent biliary decompression needs to be done in case of severe acute cholangitis. However, it remains to be determined how early biliary decompression should be performed and elective intervention would be comparable to urgent intervention, in case of mild to moderate choledocholithiasis associated cholangitis.One hundred ninety-five patients were enrolled who were diagnosed with mild to moderate cholangitis with common bile duct (CBD) stones between January 2006 and August 2010. They were divided into two groups according to door to intervention time, and urgent (≤24 h, n = 130) versus elective (24 h, n = 82). Primary outcomes of this study were technical success rate (CBD stones removal) and clinical success rate (improvement of cholangitis) between the two groups. Hospital stay and intervention-related complications were also evaluated.There was no statistically significant difference in technical, clinical success rate and intervention-related complications between the urgent and elective groups (P = 0.737, 0.285, 0.398, respectively). Patients in the urgent group had significantly shorter hospitalization than in the elective group (6.8 vs. 9.2 days, P0.001), and furthermore, intervention to discharge time was also significantly shorter by 1.1 days in the urgent group (P = 0.035). In terms of laboratory parameters, initial CRP level was the only factor correlated with hospital stay and intervention to discharge time.This study demonstrates that urgent ERCP would be recommended in the management of patients with CBD stone-related mild to moderate acute cholangitis because of the advantage of short hospital stay and intervention to discharge time.

Developmental genes are known to regulate cell proliferation, migration, and differentiation; thus, it comes as no surprise that the misregulation of developmental genes plays an important role in the biology of human cancers. One such pathway that has received an increasing amount of attention for its function in carcinogenesis is the Hedgehog (Hh) pathway. Initially the domain of developmental biologists, the Hh pathway and one of its ligands, Sonic Hedgehog (Shh), have been shown to play an important role in body planning and organ development, particularly in the foregut endoderm. Their importance in human disease became known to cancer biologists when germline mutations that resulted in the unregulated activity of the Hh pathway were found to cause basal cell carcinoma and medulloblastoma. Since then, misexpression of the Hh pathway has been shown to play an important role in many other cancers, including those of the pancreas. In many institutions, investigators are targeting misexpression of the Hh pathway in clinical trials, but there is still much fundamental knowledge to be gained about this pathway that can shape its clinical utility. This review will outline the evolution of our understanding of this pathway as it relates to the pancreas, as well as how the Hh pathway came to be a high-priority target for treatment.

After failed biliary cannulation with needle knife sphincterotomy (NKS), endoscopic retrograde cholangiopancreatography (ERCP) is sometimes repeatedly performed in clinically stable patients; however, there are few reports about the results. This study assessed the results of repeated ERCPs after failure with NKS.After failed NKS, patients who underwent repeated ERCP for the same purpose within 3 days were retrospectively identified. Success was defined as deep placement of a catheter into the common bile duct.Sixty-nine patients underwent a second ERCP procedure and, of those, six underwent a third ERCP. Of the 69 patients, cannulation was successful in 76.8% (53/69): 46 of 58 patients without additional NKS and 7 of 11 with additional NKS. Success increased to 79.7% (55/69) after the results of the third ERCP were included. Common causes of failed NKS were biliary deep cannulation failure (78.3%) and blocking of the endoscopic view due to bleeding (13.0%). There was a significant difference in success rates between the one day (65.7%) and the combined 2-3 day (88.2%) cases (P = 0.027). Except for the interval between ERCPs, there were no other factors associated with success rates. Complications occurred in 8, 11, and one patient after initial, second, and third ERCP and there was no difference of complication rates between each ERCPs.In cases with biliary cannulation failure with NKS, it is more worthwhile repeating ERCP 2 or 3 days after such failure than one day after, if the patient's condition permits delay of procedure.

Background/Aims: Bacteremia following endoscopic retrograde cholangiopancreatography (ERCP) is a severe complication, but the risk factors for this condition have not yet been clearly determined. Thus, the aim of this study was to investigate the risk factors of post-ERCP bacteremia. Methods: Among patients who underwent ERCP from June 2006 to May 2009, we selected patients without any signs of infection prior to the ERCP procedures. Of these patients, we further selected those who experienced bacteremia after ERCP as well as two-fold age and sex-matched controls who did not experience bacteremia after ERCP procedures. We compared clinical, laboratory and technical aspects between these two groups. Results: There were 70 patients (3.1%) who developed bacteremia after ERCP. In the multivariate analysis, a history of previous liver transplantation, an elevated serum alkaline phosphatase level and an endoscopic retrograde biliary drainage procedure were independent risk factors of post-ERCP bacteremia (p=0.006, p=0.001, and p=0.004, respectively). The microbiologic analysis revealed the presence of gram-negative organisms in 80% of the cases, and 11 patients had infections with bacteria expressing extended spectrum β-lactamases. Pseudomonas infection was significantly more common in patients who received liver transplantation as compared to patients without transplantation (p=0.014). Conclusions: A history of liver transplantation, elevated serum alkaline phosphatase levels and endoscopic retrograde biliary drainage procedure were independent risk factors of post-ERCP bacteremia and require additional attention in future studies.

Most pancreatic ductal adenocarcinomas (PDACs) metastasize even after curative resection. Our goal was to investigate the important factors affecting metastasis and overall survival (OS).We studied 88 PDACs with R0 resection and evaluated immunohistochemical markers on tissue microarrays to assess the expression levels of the following: EGFR, amphiregulin, VEGF, p-c-met, MMP2, MMP7, MMP9, CXCR3, and CXCR4.The median OS in patients who had positive versus negative expression of AREG and MMP9 were 25 versus 16 months and 24 versus 13 months, respectively (P = 0.03, P = 0.006). However, the median OS in patients with positive versus negative expression of MMP2 was 22 versus 37 months (P = 0.04). Immunoprofiles also revealed that patients with positive expression of p-c-met or VEGF had significantly shorter distant metastasis-free survival. Adjuvant treatment, postoperative decrease of CA 19-9, angiolymphatic invasion, AREG, and MMP2 were independent prognostic factors affecting OS in multivariate analysis.Immunoprofiles revealed the groups with unfavorable tumor biology: negative expression of AREG and positive expression of MMP2. Also, high immunoreactivity of p-c-met or VEGF seemed to be associated with early distant organ metastasis in R0 resected PDACs; however, they still need to be further investigated. These results may give us useful insights in understanding the tumor biology and the patterns of PDAC dissemination.

BACKGROUND AND PURPOSE: Only 1 ultrasonography study that described the variation of the VN had been published at the time our research was begun. The purpose of this study was to evaluate the incidence and type of variation in the course of the cervical VN on thyroid ultrasonography. MATERIALS AND METHODS: From August 2009 to September 2010, 163 consecutive patients were evaluated by sonography for the screening and characterization of thyroid nodules (mean age, 49.0 ± 14.4 years, male:female, 20:143). Two types of variation were defined as follows: 1) anterior variation, when the course of the VNs changed from the typical location to an anterior location in front of the CCA; and 2) medial variation, when the course of the VNs changed from the typical location to a location medial to the CCA (between CCA and thyroid gland). The incidence of the each variation was studied. RESULTS: Variation in the course of the VN occurred in 5.5% (18/326) of cases. The anterior variation was observed in 4.3% (14/326, right:left = 4:10), and the medial variation was observed in 1.2% (4/326, right:left = 3:1). For both variations, the VN was close to or nearly abutted the thyroid gland after it changed course. CONCLUSIONS: Variation in the course of the cervical VN could be assessed by ultrasonography. Two variations were observed in 5.5% of cases. The anterior variation was more common than the medial variation.