JAK2 Loss Arising From Tumor-Spread-Through-Air-Spaces (STAS) Promotes Tumor Progression by Suppressing CD8+ T Cells in Lung Adenocarcinoma: A Machine Learning Approach.

BACKGROUND: Tumor spread through air spaces (STAS) is a recently discovered risk factor for lung adenocarcinoma (LUAD). The aim of this study was to investigate specific genetic alterations and anticancer immune responses related to STAS. By using a machine learning algorithm and drug screening in lung cancer cell lines, we analyzed the effect of Janus kinase 2 (JAK2) on the survival of patients with LUAD and possible drug candidates. METHODS: This study included 566 patients with LUAD corresponding to clinicopathological and genetic data. For analyses of LUAD, we applied gene set enrichment analysis (GSEA), in silico cytometry, pathway network analysis, in vitro drug screening, and gradient boosting machine (GBM) analysis. RESULTS: The patients with STAS had a shorter survival time than those without STAS (P < 0.001). We detected gene set-related downregulation of JAK2 associated with STAS using GSEA. Low JAK2 expression was related to poor prognosis and a low CD8+ T-cell fraction. In GBM, JAK2 showed improved survival prediction performance when it was added to other parameters (T stage, N stage, lymphovascular invasion, pleural invasion, tumor size). In drug screening, mirin, CCT007093, dihydroretenone, and ABT737 suppressed the growth of lung cancer cell lines with low JAK2 expression. CONCLUSION: In LUAD, low JAK2 expression linked to the presence of STAS might serve as an unfavorable prognostic factor. A relationship between JAK2 and CD8+ T cells suggests that STAS is indirectly related to the anticancer immune response. These results may contribute to the design of future experimental research and drug development programs for LUAD with STAS.

Diagnostic Assessment of Endoscopic Ultrasonography-Fine Needle Aspiration Cytology in the Pancreas: A Comparison between Liquid-Based Preparation and Conventional Smear.

Background and Objectives: This study aimed to elucidate the cytologic characteristics and diagnostic usefulness of endoscopic ultrasonography-fine needle aspiration cytology (EUS-FNAC) by comparing it with liquid-based preparation (LBP) and conventional smear (CS) in pancreas. Methods: The diagnostic categories (I through VII) were classified according to the World Health Organization Reporting System for Pancreaticobiliary Cytopathology. Ten cytologic features, including nuclear and additional features, were evaluated in 53 cases subjected to EUS-FNAC. Nuclear features comprised irregular nuclear contours, nuclear enlargement, hypochromatic nuclei with parachromatin clearing, and nucleoli. Additional cellular features included isolated atypical cells, mucinous cytoplasm, drunken honeycomb architecture, mitosis, necrotic background, and cellularity. A decision tree analysis was conducted to assess diagnostic efficacy. Results: The diagnostic concordance rate between LBP and CS was 49.1% (26 out of 53 cases). No significant differences in nuclear features were observed between categories III (atypical), VI (suspicious for malignancy), and VII (malignant). The decision tree analysis of LBP indicated that cases with moderate or high cellularity and mitosis could be considered diagnostic for those exhibiting nuclear atypia. Furthermore, in CS, mitosis, isolated atypical cells, and necrotic background exerted a more significant impact on the diagnosis of EUS-FNAC. Conclusions: Significant parameters for interpreting EUS-FNAC may differ between LBP and CS. While nuclear atypia did not influence the diagnosis of categories III, VI, and VII, other cytopathologic features, such as cellularity, mitosis, and necrotic background, may present challenges in diagnosing EUS-FNAC.

A Comparison of Clinical Outcomes between Endoscopic Resection and Surgical Resection in Ampullary Tumors.

Background and objectives: This study aimed to elucidate the clinical outcomes of endoscopic resection (ER) through comparison with surgical resection (SR) through a meta-analysis. Materials and Methods: This meta-analysis was performed using 32 studies. The complete resection and recurrence rates of treatment for ampullary tumors were investigated and compared between ER and SR. In addition, complications, including pancreatitis, cholangitis, cholecystitis, perforation, and papillary stenosis, and mortality of ER and SR, respectively, were estimated. Results: The rates of complete resection were 0.812 (95% confidence interval, CI, 0.758-0.856) and 0.929 (95% CI 0.739-0.984) in ER and SR, respectively. Recurrence rates were 0.145 (95% CI 0.107-0.193) and 0.126 (95% CI 0.057-0.257) in ER and SR, respectively. There were no significant differences in complete resection and recurrence rates between ER and SR in the meta-regression tests (p = 0.164 and p = 0.844, respectively). The estimated rates of pancreatitis, cholangitis/cholecystitis, perforation, and papillary stenosis were 12.8%, 4.4%, 5.2%, and 4.3% in ER and 9.9%, 5.6%, 2.3%, and 5.6% in SR, respectively. There was no significant difference in complications between ER and SR. The mortality rate of SR was slightly higher than that of ER (0.041, 95% CI 0.015-0.107 vs. 0.031, 95% CI 0.005-0.162). Our results show that ER had no significant differences in terms of complete resection and recurrence rates compared to SR, regardless of tumor behaviors. Conclusions: By comparing the complication and mortality rates between ER and SR, the safety of ER was proven.

Antibacterial activity and mechanism of action of analogues derived from the antimicrobial peptide mBjAMP1 isolated from Branchiostoma japonicum.

Objectives: The worldwide increase in antibiotic-resistant bacteria is a growing threat to public health. Antimicrobial peptides (AMPs) are potentially effective alternatives to conventional antibiotics. We therefore tested analogues of the AMP mBjAMP1 from Branchiostoma japonicum, which we produced by adding and/or replacing amino acids to increase antimicrobial activity against Gram-negative bacteria. Methods: We compared the antimicrobial activities of mBjAMP1 analogues against Gram-negative bacteria reference strains and 52 strains of Klebsiella pneumoniae isolated from patients. Antibiofilm activity and cytotoxicity were evaluated, and the mechanisms of action were then studied. Results: Analogue peptides exhibited greater antimicrobial and antibiofilm activities than mBjAMP1. In particular, the analogue IARR-Anal10 displayed not only the greatest antimicrobial and antibiofilm activities, but also no toxicity against human red blood cells or other mammalian cells. IARR-Anal10 had little or no effect on bacterial outer membrane permeability, membrane polarization or membrane integrity. Instead, it appears IARR-Anal10 binds bacterial DNA, as evidenced in DNA gel retardation assays. Thus, IARR-Anal10 likely kills bacteria through an intracellular mechanism. We also confirmed that IARR-Anal10 suppresses the virulence of K. pneumoniae to a degree similar to tigecycline, used to treat carbapenem-resistant Enterobacteriaceae infections. Notably, IARR-Anal10 did not induce development of resistance by K. pneumoniae, though both meropenem and tigecycline did so within a short time. Conclusions: These results suggest that IARR-Anal10 is a promising agent for treating infections caused by bacteria resistant to tigecycline and meropenem.

The usefulness of contrast-enhanced harmonic EUS-guided fine-needle aspiration for evaluation of hepatic lesions (with video).

BACKGROUND AND AIMS: Small hepatic masses often do not have distinct margins on B-mode EUS images. Contrast-enhanced harmonic EUS (CEH-EUS) is widely used for evaluating ambiguous pancreatic lesions. However, its role in detecting hepatic lesions and the use of EUS-guided FNA are not well evaluated. We investigated the usefulness of CEH-EUS-guided FNA for evaluating hepatic lesions. METHODS: Thirty consecutive patients with hepatic masses underwent CEH-EUS and CEH-EUS-guided FNA between September 2010 and November 2016. RESULTS: Twenty-eight patients (93.3%) had malignant tumors and 2 patients (6.7%) had benign hepatic masses. Before contrast enhancement, 73.3% of the hepatic lesions (22/30) in the patient cohort were visible on B mode. After contrast enhancement, 93.3% of these hepatic lesions (28/30) were distinguishable from the surrounding liver parenchyma. The technical success rate was 100%. The median tumor size on EUS and the number of needle passes were 24.5 mm (interquartile range [IQR], 14.5-40.8) and 2 (IQR, 2-3), respectively. The diagnostic accuracy of CEH-EUS-guided FNA was 86.7% (26/30 cases). There were no procedure-related adverse events. CONCLUSIONS: CEH-EUS-guided FNA can be a safe and efficient method for the diagnosis of hepatic masses. It can result in high diagnostic accuracy in cases where the hepatic lesions are poorly visible on conventional EUS.

Invasion Depth Measured in Millimeters is a Predictor of Survival in Patients with Distal Bile Duct Cancer: Decision Tree Approach.

BACKGROUND: AJCC staging system is unreliable for predicting survival in distal bile duct (DBD) cancer patients, due to inter-observer variation. Measured depth of invasion (DOI) is suggested to be more accurate to predict patients' clinical outcome in extra-hepatic cholangiocarcinomas, but its significance in DBD cancer and cutoff values are still debatable. This study aimed to identify the optimal cutoff value of DOI in relation to prognosis in DBD cancer patients. METHODS: Data of 179 patients with DBD adenocarcinoma treated in three institutions were investigated. Under microscopic review, DOI was measured. The relationships between the clinicopathological parameters and the groups based on DOI (≤3; 3-10; >10 mm) were evaluated, and the survival times of each group based on DOI and T classification were compared. RESULTS: Deeply invading tumors exhibited a greater tendency toward the infiltrative type, high histological grade, AJCC stage, and pancreatic, duodenal, lymphovascular and perineural invasion. The measured DOI was significantly correlated with worse relapse-free and overall survival (all p < 0.05). In multivariate analyses, the DOI remained as one of the prognostic factors (all p < 0.05), while T classification was not a significant prognostic factor. The new prognostic models (low, intermediate, and high risk) that applied DOI and nodal metastasis showed significant difference in recurrence and survival rate (all p < 0.05). CONCLUSIONS: On the basis of the proposed cutoff value, the DOI could be clear and meaningful, overcoming the vagueness of the T classification for predicting clinical outcomes in patients with DBD carcinoma.

A High Ki67/BCL2 Index Could Predict Lower Disease-Free and Overall Survival in Intestinal-Type Gastric Cancer.

BACKGROUND: The heterogeneity of gastric cancer makes the identification of potential prognostic indicators particularly important. The Ki67 and BCL2 proteins are known prognostic markers for different types of cancer. Ki67 is associated with cell proliferation, whereas BCL2 has antiproliferative roles. A combined marker based on these opposite functions might provide improved prognostic information in gastric cancer. METHOD: Ki67 and BCL2 expression was assessed in 276 gastric adenocarcinoma tissue microarrays. A Ki67/BCL2 index based on the relative expression of each protein was divided into low- and high-risk groups using receiver operating characteristic curves. RESULTS: A high Ki67/BCL2 index significantly correlated with advanced stage, recurrence, intestinal type, high histologic grade, and lymphatic and perineural invasion (all p < 0.05). Univariate and multivariate analyses revealed a significant relationship between disease-free or overall survival and the Ki67/BCL2 index in intestinal-type gastric cancer (all p < 0.05). CONCLUSIONS: A combined marker using Ki67 and BCL2 could be a useful indicator for predicting survival in patients with intestinal-type gastric cancer.

Synergistic effects and antibiofilm properties of chimeric peptides against multidrug-resistant Acinetobacter baumannii strains.

The increasing prevalence of drug-resistant pathogens highlights the need to identify novel antibiotics. Here we investigated the efficacies of four new antimicrobial peptides (AMPs) for potential drug development. The antibacterial activities, synergistic effects, and antibiofilm properties of the four chimeric AMPs were tested against Acinetobacter baumannii, an emerging Gram-negative, nosocomial, drug-resistant pathogen. Nineteen A. baumannii strains resistant to ampicillin, cefotaxime, ciprofloxacin, tobramycin, and erythromycin were isolated at a hospital from patients with cholelithiasis. All four peptides exhibited significant antibacterial effects (MIC=3.12 to 12.5 µM) against all 19 strains, whereas five commercial antibiotics showed little or no activity against the same pathogens. An exception was polymyxin, which was effective against all of the strains tested. Each of the peptides showed synergy against one or more strains when administered in combination with cefotaxime, ciprofloxacin, or erythromycin. The peptides also exhibited an ability to prevent biofilm formation, which was not seen with cefotaxime, ciprofloxacin, or erythromycin, though polymyxin also inhibited biofilm formation. Indeed, when administered in combination with ciprofloxacin, the AMP HPMA exerted a potent synergistic effect against A. baumannii biofilm formation. Collectively, our findings indicate that the AMPs tested have no cytotoxicity but possess potent antibacterial and antibiofilm activities and may act synergistically with commercial antibiotics.

Melatonin attenuates dextran sodium sulfate induced colitis with sleep deprivation: possible mechanism by microarray analysis.

BACKGROUND: Inflammatory bowel disease is a chronic inflammatory condition of the gastrointestinal tract. It can be aggravated by stress, like sleep deprivation, and improved by anti-inflammatory agents, like melatonin. We aimed to investigate the effects of sleep deprivation and melatonin on inflammation. We also investigated genes regulated by sleep deprivation and melatonin. METHODS: In the 2% DSS induced colitis mice model, sleep deprivation was induced using modified multiple platform water bath. Melatonin was injected after induction of colitis and colitis with sleep deprivation. Also mRNA was isolated from the colon of mice and analyzed via microarray and real-time PCR. RESULTS: Sleep deprivation induced reduction of body weight, and it was difficult for half of the mice to survive. Sleep deprivation aggravated, and melatonin attenuated the severity of colitis. In microarrays and real-time PCR of mice colon tissues, mRNA of adiponectin and aquaporin 8 were downregulated by sleep deprivation and upregulated by melatonin. However, mRNA of E2F transcription factor (E2F2) and histocompatibility class II antigen A, beta 1 (H2-Ab1) were upregulated by sleep deprivation and downregulated by melatonin. CONCLUSION: Melatonin improves and sleep deprivation aggravates inflammation of colitis in mice. Adiponectin, aquaporin 8, E2F2 and H2-Ab1 may be involved in the inflammatory change aggravated by sleep deprivation and attenuated by melatonin.

CLDN18: Clinical, Pathological, and Genetic Signatures with Drug Screening in Gastric Adenocarcinoma.

INTRODUCTION: The CLDN18 gene, encoding claudin 18.1 and claudin 18.2, is a key component of tight junction strands in epithelial cells that form a paracellular barrier that is critical in Stomach Adenocarcinoma (STAD). METHODS: Our study included 1,095 patients with proven STAD, 415 from The Cancer Genome Atlas (TCGA) cohort and 680 from the Gene Expression Omnibus database. We applied various analyses, including gene set enrichment analysis, pathway analysis, and in vitro drug screening to evaluate survival, immune cells, and genes and gene sets associated with cancer progression, based on CLDN18 expression levels. Gradient boosting machine learning (70% for training, 15% for validation, and 15% for testing) was used to evaluate the impact of CLDN18 on survival and develop a survival prediction model. RESULTS: High CLDN18 expression correlated with worse survival in lymphocyte-poor STAD, accompanied by decreased helper T cells, altered metabolic genes, low necrosis-related gene expression, and increased tumor proliferation. CLDN18 expression showed associations with gene sets associated with various stomach, breast, ovarian, and esophageal cancers, while pathway analysis linked CLDN18 to immunity. Incorporating CLDN18 expression improved survival prediction in a machine learning model. Notably, nutlin-3a and niraparib effectively inhibited high CLDN18-expressing gastric cancer cells in drug screening. CONCLUSION: Our study provides a comprehensive understanding of the biological role of CLDN18-based bioinformatics and machine learning analysis in STAD, shedding light on its prognostic significance and potential therapeutic implications. To fully elucidate the molecular intricacies of CLDN18, further investigation is warranted, particularly through in vitro and in vivo studies.

Clinicopathological significance and prognostic implication of nuclear fatty acid-binding protein 4 expression in colorectal cancer.

This study aimed to evaluate the clinicopathological significance and prognostic role of fatty acid-binding protein 4 (FABP4) expression in colorectal cancer (CRC). Nuclear expression of FABP4 was investigated by immunohistochemistry for FABP4 on 246 human CRC tissues. The correlations between FABP4 expression, and clinicopathological characteristics and survival, was evaluated in patients with CRC. FABP4 was expressed in 91 of the 246 CRC tissues (37.0%). FABP4 expression was significantly correlated with older age, right-sided colon cancer, perineural invasion, higher pT stage, lymph node metastasis, and higher pTNM stage. However, there was no significant correlation between FABP4 expression and sex, tumor size, tumor differentiation, vascular or lymphatic invasion, or distant metastasis. Nuclear FABP4 expression was not significantly correlated with cytoplasmic FABP4 expression (P = 0.412). FABP4 expression was significantly correlated with nuclear pNF-κB expression (P = 0.001), and was significantly higher in CRC with a low immunoscore than in CRC with a high immunoscore (P < 0.001). There were significant correlations between FABP4 expression and worse overall and recurrence-free survival rates (P < 0.001 and P = 0.007, respectively). FABP4 expression was significantly correlated with aggressive tumor behaviors and pathological characteristics. In addition, patients with CRC with FABP4 expression had worse survival rates.

Prognostic impact of chemerin expression in colorectal cancer: A detailed analysis based on histological components and meta-analysis.

This study aimed to elucidate the clinicopathological significance of chemerin immunohistochemical expression in colorectal cancer (CRC) based on histologic components. Immunohistochemistry was performed to detect chemerin in 266 human CRC tissues. Correlation between chemerin expression, clinicopathological characteristics, and survival in CRC. A meta-analysis was performed to claify the prognostic role of chemerin tissue expression in malignant tumors. Chemerin was expressed in 125 of 266 CRC tissues (47.0 %) and was significantly correlated with distant metastasis (P = 0.012). However, no significant correlation was observed between chemerin expression and other clinicopathological parameters. Subgroup analyses based on histological components showed that chemerin expression was significantly higher in CRCs with the mucinous component than in those without the mucinous component (P 0.001). However, there was no significant correlation between chemerin expression and the micropapillary component. Patients with chemerin expression had worse overall and recurrence-free survival rates (P = 0.017 and P = 0.009, respectively). The prognostic significance of chemerin was found in CRCs without the mucinous component but not in those with the mucinous component. Chemerin expression was significantly correlated with poor survival in breast and ovarian cancers in the meta-analysis. Chemerin expression significantly correlated with distant metastasis and poor survival in CRCs. The predictive role of patient prognosis is useful for CRCs, especially those with no mucinous component.

Clinicopathological significance and the associated signaling pathway of p21-activated kinase 1 (PAK1) in colorectal cancer.

The aim of this study was to evaluate the clinicopathological significance and associated signaling pathways of p21-activated kinase 1 (PAK1) in colorectal cancer (CRC). PAK1 immunohistochemical expression was investigated in 246 human CRC tissues to evaluate its clinicopathological significance and prognostic role. Correlations between PAK1 and the immunoscore, HIF-1α, and pFOXO1 were also evaluated. PAK1 was expressed in 169 of 246 CRC tissues (68.7%). PAK1 expression significantly correlated with the metastatic lymph node ratio (P = 0.023). However, PAK1 expression did not correlate with tumor size, tumor location, tumor differentiation, lymphovascular and perineural invasion, or distant metastasis. PAK1 expression was significantly higher in CRC with a low immunoscore than in CRC with a high immunoscore (P = 0.017). In addition, there were significant correlations between PAK1, HIF-1α, and pFOXO1 expression (P = 0.001 and P = 0.024, respectively). Patients with PAK1 expression had worse overall and recurrence-free survival than those without PAK1 expression (P 0.001 and P = 0.001, respectively). PAK1 expression was significantly correlated with worse prognosis in CRCs patients. In addition, PAK1 expression was significantly correlated with a low immunoscore and high expression of HIF-1α and pFOXO1 in CRCs.

High PPFIA1 expression promotes cancer survival by suppressing CD8+ T cells in breast cancer: drug discovery and machine learning approach.

BACKGROUND: PTPRF-interacting protein alpha 1 (PPFIA1) plays an important role as a regulator of cell motility and tumor cell invasion and is frequently amplified in breast cancer. The aim of this study was to investigate the clinicopathologic features, survival, anticancer immunities and specific gene sets related to high PPFIA1 expression in patients with breast cancer. We verified the importance of PPFIA1 and survival rates using machine learning and identified drugs that can effectively reduce breast cancer cells with high PPFIA1 expression. METHODS: This study analyzed clinicopathologic factors, survival rates, immune profiles and gene sets according to PPFIA1 expression in 3457 patients with breast cancer from the Kangbuk Samsung Medical Center cohort (456 cases), Molecular Taxonomy of Breast Cancer International Consortium (1904 cases) and The Cancer Genome Atlas (1097 cases). We applied gene set enrichment analysis (GSEA), in silico cytometry, pathway network analyses, in vitro drug screening, and gradient boosting machine (GBM) analysis. RESULTS: High PPFIA1 expression in breast cancer was associated with worse prognosis, with reduced tumor-infiltrating lymphocytes, especially CD8+ T cells, and increased PD-L1 expression. In pathway network analysis, PPFIA1 was linked directly to the tyrosine-protein phosphatase pathway and indirectly to immune pathways. The importance of PPFIA1's association with survival in GBM analysis was higher than that of perineural and lymphovascular invasion. In in vitro drug screening, expression of PPFIA1 on mRNA level positively correlated with sensitivity of cell lines to erlotinib. CONCLUSION: High PPFIA1 in patients with breast cancer is related to poor prognosis and decreased anticancer immune response, and erlotinib may be promising for development of therapeutic approaches in patients with tumors overexpressing PPFIA1.

Hypertriglyceridaemic waist phenotype and waist circumference triglyceride index are associated with higher incidence of acute pancreatitis: a nationwide population-based retrospective cohort study.

OBJECTIVES: The hypertriglyceridaemic waist (HTGW) phenotype, an indicator to assess metabolic syndrome, could be a useful predictive marker for the risk of acute pancreatitis. This study aimed to evaluate the association between the HTGW phenotype and the risk of acute pancreatitis with a nationwide population-based cohort. DESIGN: A retrospective, nationwide cohort study. SETTING: Registry of health check-up result from Korean National Health Insurance Service. PARTICIPANTS: A total of 3 912 551 adults who underwent health checkups under the National Health Insurance Service in 2009 were enrolled in this study. INTERVENTIONS: Subjects with both increased waist circumference (WC) and elevated blood triglyceride concentrations were defined as the HTGW phenotype. The participants were divided into four groups, classified as NWNT (normal WC-normal triglycerides), EWNT (elevated WC-normal triglycerides), NWET (normal WC-elevated triglycerides) and HTGW. The WC triglyceride index (WTI) is a quantitative indicator of the HTGW phenotype which is calculated by multiplying WC (cm) by triglyceride levels (mmol/L). PRIMARY OUTCOME MEASURE: The subjects were followed until 31 December 2018. The adjusted HRs of acute pancreatitis in each group were estimated. RESULTS: During the follow-up, there were a total of 8933 of acute pancreatitis occurrences. The incidence of acute pancreatitis in all subjects was 0.278 per 1000 person-year. The HTGW group had the highest incidence (0.444), followed by the NWET (0.381), and EWNT (0.316) groups. The HTGW group had a significant higher incidence of acute pancreatitis than the NWNT groups (HR 1.364 (95% CI 1.279 to 1.454)). The risk of acute pancreatitis steadily increased as the WTI increased (HR 1.847 (95% CI 1.657 to 2.058) in 10th decile). CONCLUSIONS: The HTGW phenotype is confirmed to be an independent risk factor that increases the risk of acute pancreatitis.

Diagnostic Accuracy of ki-67 Labeling Index in Endoscopic Ultrasonography-Fine-Needle Aspiration Cytology and Biopsy of Pancreatic Neuroendocrine Neoplasms.

BACKGROUND: This study aimed to compare the diagnostic accuracy of the Ki-67 labeling index (LI) between endoscopic ultrasonography-fine-needle aspiration cytology/biopsy (EUS-FNAC/FNB) and surgical specimens of pancreatic neuroendocrine neoplasms (PanNENs). METHODS: Conventional meta-analysis and diagnostic test accuracy (DTA) reviews were performed on 17 eligible studies. The DTA review involved calculating the sensitivity, specificity, diagnostic odds ratio (OR), and area under the curve (AUC) of the summary receiver operating characteristic (SROC) curve. In addition, subgroup analysis was conducted based on EUS-FNAC and FNB, tumor grade, and tumor size. RESULTS: The overall concordance rate of WHO grade based on Ki-67 LI between the EUS-FNAC/FNB and the surgical specimen was 0.767 (95% confidence interval (CI), 0.713-0.814). Concordance rates of the EUS-FNAC and EUS-FNB subgroups were 0.741 (95% CI, 0.681-0.794) and 0.839 (95% CI, 0.738-0.906), respectively. In the DTA review for grade 3, the sensitivity and specificity were calculated to be 0.786 (95% CI, 0.590-0.917) and 0.998 (95% CI, 0.987-1.000), respectively. The diagnostic OR and AUC of the SROC curve were 150.220 (95% CI, 46.145-489.000) and 0.983, respectively. The sensitivity and specificity were observed to be highest in the grade 1 and 3 subgroups, respectively. CONCLUSIONS: Higher concordance of tumor grade based on Ki-67 LI was observed between EUS-FNAC/FNB and surgical specimens, indicating the potential usefulness of Ki-67 LI in predicting PanNEN tumor grade in EUS-FNAC/FNB.

National Survey Regarding the Management of Difficult Bile Duct Stones in South Korea.

Background/Aims: This study aimed to investigate the patterns of preferred endoscopic procedure types and techniques for managing difficult common bile duct (CBD) stones in South Korea. Methods: The Committee of Policy and Quality Management of Korean Pancreatobiliary Association (KPBA) conducted a survey containing 19 questions. Both paper and online surveys were carried out; with the paper survey being conducted during the 2019 Annual Congress of KPBA and the online survey being conducted through Google Forms from April 2020 to February 2021. Results: The response rate was approximately 41.3% (86/208). Sixty-two (73.0%) worked at tertiary hospitals or academic medical centers, and 60 (69.7%) had more than 5 years of endoscopic retrograde cholangiopancreatography experience. The preferred size criteria for large CBD stones were 15 mm (40.6%), 20 mm (31.3%), and 30 mm (4.6%). For managing of large CBD stones, endoscopic papillary large balloon dilation after endoscopic sphincterotomy was the most preferred technique (74.4%). When performing procedures in those with bleeding diathesis, 64 (74.4%) respondents favored endoscopic papillary balloon dilation (EPBD) alone or EPBD with small endoscopic sphincterotomy. Fifty-five respondents (63.9%) preferred the doubleguidewire technique when faced with difficult bile duct cannulation in patients with periampullary diverticulum. In surgically altered anatomies, cap-fitted forward viewing endoscopy (76.7%) and percutaneous transhepatic cholangioscopy (48.8%) were the preferred techniques for Billroth-II anastomosis and total gastrectomy with Roux-en-Y anastomosis, respectively. Conclusions: Most respondents showed unifying trends for the management of difficult CBD stones. The current practice patterns could be used as basic data for clinical quality improvements in the management of difficult CBD stones.

Current Practice Patterns of Endoscopic Ultrasound-Guided Tissue Sampling for Pancreatic Solid Mass in Korea: Outcomes of a National Survey.

Background/Aims: Although endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) and fine needle biopsy (FNB) are widely used for tissue acquisition of pancreatic solid mass, the optimal strategy of this procedure has not been established yet. The aim of this nationwide study was to investigate the current practice patterns of EUS-FNA/FNB for pancreatic solid mass in Korea. Methods: The Policy-Quality Management of the Korean Pancreatobiliary Association (KPBA) developed a questionnaire containing 22 questions. An electronic survey consisting of the questionnaire was distributed by e-mail to members registered to the KPBA. Results: A total of 101 respondents completed the survey. Eighty respondents (79.2%) performed preoperative EUS-FNA/FNB for operable pancreatic solid mass. Acquire needles (60.4%) were used the most, followed by ProCore needles (47.5%). In terms of need size, most respondents (>80%) preferred 22-gauge needles regardless of the location of the mass. Negative suction with a 10-mL syringe (71.3%) as sampling technique was followed by stylet slow-pull (41.6%). More than three needle passes for EUS-FNA/FNB was performed by most respondents (>80%). The frequency of requiring repeated procedure was significantly higher in respondents with a low individual volume (<5 per month, p=0.001). Prophylactic antibiotics were routinely used in 39 respondents (38.6%); rapid on-site pathologic evaluation was used in 6.1%. Conclusions: According to this survey, practices of EUS-FNA/FNB for pancreatic solid mass varied substantially, some of which differed considerably from the recommendations present in existing guidelines. These results suggest that the development of evidence-based quality guidelines fitting Korean clinical practice is needed to establish the optimal strategy for this procedure.

Minimizing radiation exposure in endoscopic retrograde cholangiopancreatography: a review for medical personnel.

Fluoroscopy is used frequently during endoscopic procedures, such as endoscopic retrograde cholangiopancreatography (ERCP). However, exposure to radiation is an important health concern, primarily because of the potential increase in the lifetime risk of malignancy. This consideration is important for patients and staff exposed to radiation during ERCP. Thus, an understanding of how radiation doses are measured during ERCP and the potential risks of this radiation is important. Additionally, staff must be educated about methods used to minimize the radiation dose, such as the use of different imaging techniques, the general principles of fluoroscopy, and advances in hardware and software. The use of personal protective equipment is also essential to minimize occupational exposure. However, no comprehensive ERCP guideline on the use of X-ray systems in clinical settings or on radiation protection for operators has been established. This review focuses on the properties of fluoroscopy systems and methods of radiation protection for physicians and assistants participating in ERCP.

The Predicting Role of the Neutrophil-to-Lymphocyte Ratio for the Tumor Grade and Prognosis in Pancreatic Neuroendocrine Tumors.

This study aims to investigate the prognostic role of the neutrophil-to-lymphocyte ratio (NLR) in pancreatic neuroendocrine tumors (PNETs) using meta-analysis. This study evaluates the correlation between the NLR and the prognosis in PNETs from nine eligible studies. In addition, a subgroup analysis based on the tumor grade, treatment, and evaluation criteria, was conducted. The estimated rate of a high NLR was 0.253 (95% confidence interval (CI) 0.198-0.317). The rate of high NLRs was significantly lower in patients with lower tumor grades (G1) than those with higher tumor grades (G2 or G3). In addition, the mean value of the NLR was significantly lower in lower tumor grades than in higher tumor grades. High NLRs were significantly correlated with worse overall and recurrence-free survivals (hazard ratio (HR) 2.180, 95% CI 1.499-3.169 and HR 2.462, 95% CI 1.677-3.615, respectively). In a subgroup analysis, the prognostic implications of the NLR were found in both higher and lower criteria of a high NLR. Taken together, our results show that the NLR could be useful for predicting the tumor grade and the prognosis in PNETs.