Comparison of clinical/histological outcomes according to puncture sites in endoscopic ultrasound-guided fine needle biopsy for large pancreatic masses: Multicenter randomized prospective pilot study.

OBJECTIVES: There are no recommendations regarding the optimal puncture site in endoscopic ultrasound-guided fine needle biopsy (EUS-FNB). This multicenter randomized prospective study compared the diagnostic accuracy and histological findings according to the sampling site for pancreatic masses larger than 3 cm. METHODS: Consecutive patients with pancreatic masses larger than 3 cm indicated for EUS-FNB were included in the study. Patients were randomly assigned to two groups for the initial puncture site (central vs. peripheral sampling of the masses). A minimum of four passes were performed, alternating between the center and the periphery. The primary outcome was diagnostic accuracy. RESULTS: A total of 100 patients were equally divided into the central group and the peripheral group. The final diagnosis revealed malignancy in 95 patients (pancreatic cancer [n = 89], neuroendocrine tumor [n = 4], lymphoma [n = 1], metastatic carcinoma [n = 1]), and benign conditions in five patients (chronic pancreatitis [n = 4], autoimmune pancreatitis [n = 1]). There was no significant difference in diagnostic accuracy between the puncture sites. However, combining samples from both areas resulted in higher diagnostic accuracy (97.0%) compared to either area alone, with corresponding values of 88.0% for the center (P = 0.02) and 85.0% for the periphery (P = 0.006). CONCLUSIONS: Both central sampling and peripheral sampling showed equivalent diagnostic accuracy in detecting malignancy. However, combining samples from both areas generated superior diagnostic yield compared to using either sampling site alone. For pancreatic masses larger than 3 cm, it is advisable to consider sampling from various areas of the masses to maximize the diagnostic yield.

Effect of bowel preparation completion time on bowel cleansing efficacy: Prospective randomized controlled trial of different bowel preparation completion times precolonoscopy.

OBJECTIVES: The elapse time between the completion of bowel cleansing and colonoscopy is one of the important factors for proper bowel cleansing. Although several studies have reported that a short time interval resulted in a favorable bowel cleansing, no randomized controlled trial (RCT) has been conducted to determine the effect of the elapse time. Consequently, we performed an RCT to investigate the efficacy of bowel preparation of participants who underwent colonoscopy according to the different time intervals between the completion of bowel preparation and colonoscopy. METHODS: In this single-center RCT, study participants were randomized to complete bowel preparation either 2-4 h or 4-8 h before colonoscopy. The primary end-point was successful bowel preparation, rated using the Boston Bowel Preparation Scale (BBPS). RESULTS: A total of 504 individuals were included (2-4 h, 255; 4-8 h, 249). The rate of successful bowel preparation in the 2-4 h group showed noninferiority compared with that of the 4-8 h group (97.6% vs. 95.2%; rate difference, 2.5% [-0.8% to 5.7%]; Pfor noninferiority < 0.001, Pfor superiority = 0.136). The rate for perfect cleansing (a BBPS score of 9) was higher in the 2-4 h group (56.5% vs. 39.8%, P < 0.001). CONCLUSION: When bowel cleansing was finished 2-4 h before the start of colonoscopy, the overall bowel cleansing was noninferior, and perfect cleansing was superior, compared to that when cleansing was finished 4-8 h before colonoscopy.

Unilateral versus bilateral Y-type stent-in-stent metal stent insertions in inoperable malignant hilar biliary strictures: A multicenter retrospective study.

BACKGROUND: To date, there is controversy regarding unilateral versus bilateral stent placement in patients with malignant hilar biliary strictures (MHBSs). The aim of this study was to compare the clinical outcomes and complications of unilateral and bilateral (stent-in-stent method) stent placements for these patients. METHODS: We conducted a multicenter retrospective analysis of patients with inoperable MHBS who underwent endoscopic self-expandable metal stent (SEMS) placement from January 2009 to December 2019. Two groups classified according to the stent procedure method were compared for demographic, procedural, and postprocedure factors. Survival analysis for patency loss and overall survival was also conducted. RESULTS: A total of 236 subjects were included. A superior technical success rate was found in the unilateral stent group (98.8% vs. 82.5%, P < 0.001), whereas the clinical success rate was higher in the bilateral group (85.7% vs. 70.5%, P = 0.028). There was no significant difference with respect to complications or patency loss, and the bilateral group had better overall survival (P < 0.01). In the Cox proportional hazard model, MHBSs from lymph node compression were associated with a higher risk of death (HR = 9.803, P = 0.003). In contrast, bilateral SEMS insertion showed reduced postprocedural mortality (HR = 0.316, P = 0.001). CONCLUSIONS: Y-type stent-in-stent bilateral SEMSs are technically difficult but demonstrated more favorable overall survival for palliative bile drainage of inoperable MHBS patients compared to unilateral insertions.

Subsets associated with developing acute pancreatitis in patients with severe hypertriglyceridemia and the severity of pancreatitis.

BACKGROUND AND OBJECTIVES: Hypertriglyceridemia (HTG) is a rare but well-recognized cause for acute pancreatitis (AP). This study aimed to determine subsets related to development of AP in patients with severe HTG and the severity of HTG-induced AP (HTG-AP). METHODS: Patients who had severe HTG (serum triglyceride level >1,000 mg/dL) more than once between Jan. 2010 and Dec. 2017 in a single institute were evaluated retrospectively. Patients were divided into two groups, with AP or without AP, and were compared. HTG-APs in patients with severe HTG were compared to APs due to other causes during the same period. RESULTS: Sixty-three patients (19.3%) presented with AP of a total 326 patients with severe HTG. The AP group displayed younger age, more alcohol consumption and diabetes mellitus, and higher initial/maximum serum levels of triglyceride, glucose, HbA1c, total cholesterol, and calculated non-high-density lipoprotein cholesterol (p < 0.05). HTG-APs were clinically more severe compared with 277 APs due to other causes in terms of CRP (p < 0.001), CT severity index (p = 0.002), revised Atlanta classification (p < 0.001), and hospital stay (p = 0.011). In logistic regression analysis, maximum serum triglyceride level (OR 2.706, p = 0.015), alcohol consumption amount (OR 5.292, p < 0.001), and age (OR 0.358, p = 0.017) were independently associated with development of AP in patients with severe HTG. CONCLUSIONS: Development of AP in patient with severe HTG was independently associated with younger age, higher serum TG level, and more alcohol consumption. HTG-APs are clinically more severe than APs due to other causes.

Organotypic slice cultures of pancreatic ductal adenocarcinoma preserve the tumor microenvironment and provide a platform for drug response.

BACKGROUND: /Objective: The conventional models currently used to evaluate various anti-tumor therapeutic agents are not sufficient for representing human pancreatic ductal adenocarcinoma (PDA), which has a unique tumor microenvironment. We aimed to produce an organotypic slice culture model from human PDA that resembles the in vivo situation and to evaluate the responses of PDA slices to established cytotoxic drugs. METHODS: PDA tissues were obtained from 10 patients who underwent pancreatic resection. The tissues were sliced by a vibratome, and the tumor slices were then cultured. The viability of tumor slices during slice culture was evaluated using H&E and immunohistochemical staining, and stromal cells were demonstrated. The effects of cytotoxic drugs on PDA cell lines and slices were analyzed. RESULTS: Tumor slices maintained their surface areas and tissue viability for at least five days during culture. Preserved proliferation and apoptosis in tumor slices were observed by the expression of Ki-67 and cleaved caspase-3. Stromal cells including macrophages (CD68+ and CD163+), T cells (CD3+, CD8+, and FOXP3+), and myeloid cells (CD11b+) were present throughout the culture period. Staurosporine, gemcitabine, and cisplatin treatment of PDA cell lines and tumor slices exerted proportional cytotoxic effects in terms of MTT viability, tumor cell number, and Ki-67 and cleaved caspase-3 expression. CONCLUSIONS: Organotypic human PDA slice cultures preserved their viability and tumor microenvironment for at least five days during slice culture. PDA slice culture appears to be a feasible preclinical test model to assess the response to anti-tumor agents.

Effect of Dynamic Position Changes on Adenoma Detection During Colonoscope Withdrawal: A Randomized Controlled Multicenter Trial.

OBJECTIVES: Adequate luminal distension is essential for improving adenoma detection during colonoscope withdrawal. A few crossover studies have reported that dynamic position changes maximize luminal distension and increase adenoma detection rates (ADR). We designed a multicenter, randomized, parallel-group trial to verify the effect of dynamic position changes on colonic adenoma detection. METHODS: This study was conducted at the six hospitals of the Catholic University of Korea. Patients aged 45-80 years who underwent a colonoscopy for the first time were included. In the position change group, the position changes during colonoscope withdrawal were as follows: cecum, ascending colon, and hepatic flexure: left lateral position; transverse colon: supine position; splenic flexure, descending colon, sigmoid colon, and rectum: right lateral position. In the control group, the examinations were performed entirely in the left lateral position during colonoscope withdrawal. The primary outcome measure was the ADR, which was defined as the proportion of patients with ≥1 adenoma. RESULTS: A total of 1,072 patients were randomized into the position change group (536 patients) or the control group (536 patients). The ADR was higher in the position change group than in the control group (42.4 vs. 33.0%, P=0.002). More adenomas were detected per subject in the position change group (0.90 vs. 0.67, P=0.01). Increases in the number of adenomas were observed in examinations of the transverse colon (0.22 vs. 0.13, P=0.016) and the left colon (0.37 vs. 0.27, P=0.045). A significant increase in the ADR was observed for endoscopists with a relatively low detection rate. For endoscopists with a high detection rate, non-significant changes in the ADR were observed. CONCLUSIONS: Dynamic position changes during colonoscope withdrawal increased the ADR.

Interleukin-6 is associated with obesity, central fat distribution, and disease severity in patients with acute pancreatitis.

BACKGROUND/OBJECTIVE: Acute pancreatitis (AP) is a systemic inflammatory disease, and cytokines are suggested to be related to the course of AP. Obesity and central fat distribution are considered to have been associated with severe AP. This study investigated the profile of inflammatory cytokines in AP to determine how they are related to obesity, central fat distribution, and AP severity. METHODS: Fifty-nine patients with AP were prospectively enrolled in the study. Body mass index and waist circumference were obtained at admission. Serum levels of inflammatory cytokines, IL-Iß, IL-1ra, IL-6, TNF-α, sTNFR-I, and sTNFR-II, were measured on day 1 and 2 of AP. RESULTS: Of the patients included in the study, 19 (32%) were overweight, 23 (39%) had central fat distribution, and 23 (39%) had moderate AP. IL-1ra and IL-6 were significantly higher in overweight patients compared with non-overweight patients. IL-1ra, IL-6, TNF-α, and sTNFR-I were significantly higher in patients with central fat distribution compared with patients with non-central fat distribution. IL-6, sTNFR-I, and sTNFR-II were significantly higher in patients with moderate pancreatitis compared to those with mild pancreatitis. Among the six cytokines, IL-6 was commonly elevated in patients with central fat distribution, overweight, and moderate AP. The areas under the receiver operating characteristic curves of IL-6 for predicting the association with overweight, central fat distribution, and AP severity were 0.678, 0.716, and 0.801, respectively (P < 0.05). CONCLUSIONS: IL-6 is a good marker for AP severity and is associated with obesity and central fat distribution in AP patients.

Tracking incidentally discovered pancreatic cysts smaller than 30 mm: Natural course and predictors of malignancy.

BACKGROUND AND AIMS: The aim of this study was to assess the natural course and predictors of malignancy in incidentally detected small pancreatic cysts (PCs). METHOD: We retrospectively included patients with PCs smaller than 30 mm followed up with the same cross-sectional imaging modality at least 12 months apart between January 2010 and December 2019 in three academic institutions. Cyst growth, pancreatic cancer incidence, and associated factors associated with pancreatic cancer were analyzed. RESULTS: A total of 1109 patients were followed up for a median of 34 months (range, 12‒118 months). Cyst growth and rapid cyst growth (≥ 5 mm/2 years) during follow-up were observed in 20.7% and 8.3%, respectively, both with higher rates for 15‒30 mm sized PCs. Eight patients were diagnosed with pancreatic cancer. The standardized incidence ratio for pancreatic cancer in small PCs was calculated as 5.2 [95% Confidence interval (CI): 1.3‒20.5].  The development of pancreatic cancer was associated with rapid growth [hazard ratio (HR): 8.1, 95% CI: 1.5‒43.4, p = 0.015] and newly developed worrisome features (HR: 11.7, 95% CI: 1.7‒79.6, p = 0.012) in competing risk analysis. CONCLUSIONS: One-fifth of small incidentally detected PCs increased in size. Rapid growth and newly developed worrisome features were predictors of malignancy.

Characteristics of Early Pancreatic Cancer: Comparison between Stage 1A and Stage 1B Pancreatic Cancer in Multicenter Clinical Data Warehouse Study.

BACKGROUND: Little is known about the characteristics of early pancreatic cancer. We aimed to identify the characteristics, clues for early detection, and prognostic factors for early pancreatic cancer by analyzing a large number of patients with stage 1 pancreatic cancer. METHODS: A clinical data warehouse that includes databases of all the medical records of eight academic institutions was used to select and analyze patients with pancreatic cancer that had been diagnosed from January 2010 to May 2023. RESULTS: In total, 257 stage 1 pancreatic cancer patients were included. There were 134 men (52%), and the average age was 67.2 ± 9.9 years. Compared to patients with stage 1B pancreatic cancer (2-4 cm), patients with stage 1A pancreatic cancer (≤2 cm) had more tumors in the body and tail than in the head (p = 0.028), more new-onset diabetes and less old diabetes (p = 0.010), less jaundice (p = 0.020), more follow-up of IPMN (intraductal papillary mucinous neoplasm, p = 0.029), and more histories of acute pancreatitis (p = 0.013). The pathological findings showed that stage 1A pancreatic cancer involved more IPMNs (p < 0.001) and lower pancreatic intraepithelial neoplasia (p = 0.004). IPMN was present in all 13 pancreatic tumors that were smaller than 1 cm. In multivariate analysis, positive resection margin (odds ratio [OR] 1.536, p = 0.040), venous invasion (OR 1.710, p = 0.010), and perineural invasion (OR 1.968, p = 0.002) were found to be risk factors affecting disease-free survival, while old diabetes (odds ratio [OS] 1.981, p = 0.003) and perineural invasion (OR 2.270, p = 0.003) were found to be risk factors affecting overall survival. CONCLUSIONS: IPMN is closely associated with early pancreatic cancer and may provide an opportunity for early detection. The presence of perineural invasion was a crucial prognostic factor for both overall and disease-free survival in patients with stage 1 pancreatic cancer.

Size and type of periampullary duodenal diverticula are associated with bile duct diameter and recurrence of bile duct stones.

BACKGROUND AND AIM: Periampullary diverticula (PAD) are not uncommon findings during endoscopic retrograde cholangiopancreatography, but its clinical significance had not been established. To investigate the clinical characteristics associated with PAD and their relationships with the type and size of PAD in patients with common bile duct (CBD) stones was aimed. METHODS: Three hundred seventy patients undergoing endoscopic retrograde cholangiopancreatography between March 2010 and July 2012 were consecutively enrolled, and their demographics, laboratory data, and CBD stone-related characteristics according to PAD type and PAD size were analyzed. RESULTS: Mean age, mean size of CBD stones, prevalence of systemic inflammatory response syndrome, and serum C-reactive protein level differed in patients with CBD stones according to the presence or absence of PAD. The presence of PAD and positive blood culture were correlated with systemic inflammatory response syndrome (P = 0.033 and P < 0.001, respectively). The recurrence of CBD stones was more frequent, and the diameter of CBD was larger in patients with PAD type I than in those with PAD type III. Mean age and CBD diameter were lower in patients with PAD size < 15 mm than those with PAD size ≥ 15 mm. Multivariate analyses indicated that CBD diameter was related to PAD size (P = 0.002) and the recurrence of CBD stones was related to PAD type (P = 0.001). CONCLUSIONS: PAD are associated with larger CBD stones and severe cholangitis with CBD stones. CBD diameter is related to PAD size, and the recurrence of CBD stones is related to PAD type.

Incidence and risk of pancreatic cancer in patients with chronic pancreatitis: defining the optimal subgroup for surveillance.

We aimed to present the incidence and risk factors for pancreatic cancer in a multicenter retrospective cohort of patients with chronic pancreatitis (CP). Patients with ICD-10 codes for CP (K86.0, K86.1) who underwent abdominal CT or MRI between January 2010 and December 2021 in seven academic hospitals were analyzed. After exclusions, we identified 727 patients with definite CP with a median follow-up of 3.6 years (range 1.0‒12.9). During 3290 person-years of observation, pancreatic cancers were diagnosed in 16 patients (2.20%, 0.49% per year) after a median follow-up of 2.4 years (range 1.4‒6.6), with an age- and sex-standardized incidence ratio of 18.1 (95% CI 10.4‒29.5). The underlying CPs in the 16 pancreatic cancers were classified as chronic obstructive pancreatitis (10, 63%), chronic obstructive and calcifying pancreatitis (4, 25%), chronic calcifying pancreatitis (1, 6%), and autoimmune pancreatitis (1, 6%). Factors associated with pancreatic cancer development included age (HR 4.830, p = 0.006), parenchymal calcification (HR 0.213, p = 0.003), pancreatic duct stricture (HR 2.706, p = 0.048), and serum CA 19‒9 level (HR 3.567, p = 0.014). After adjustment, age over 60 years (HR 4.540, p = 0.009) and serum CA 19‒9 levels greater than 100 U/mL (HR 3.528, p = 0.015) were independent risk factors for pancreatic cancer.

Role of magnetic resonance cholangiopancreatography for choledocholithiasis: analysis of patients with negative MRCP.

OBJECTIVE: To investigate the negative predictive value of magnetic resonance cholangiopancreatography (MRCP) for common bile duct (CBD) stones and the prognosis of patients suspected to have choledocholithiasis in whom the MRCP was negative for CBD stones. METHODS: We enrolled the patients suspected to have choledocholithiasis in whom the MRCP was negative for the CBD stones between January 2008 and March 2011 and retrospectively analyzed the outcomes of 115 patients. RESULTS: Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 27 patients (23%, group 1), and none had CBD stones. The negative predictive value of MRCP was 100%. During a median follow-up of 18.3 months, acute cholangitis with newly developed CBD stones occurred in two patients. Eighty-eight patients (77%, group 2) did not undergo ERCP and all recovered from acute cholangitis without CBD surgery. During a median follow-up of 18.7 months, acute cholangitis, acute cholecystitis, gallstone pancreatitis, and pancreatico-biliary cancers occurred in four (4.6%), three (3.5%), one (1.2%), and three (3.5%) patients, respectively. New CBD stones were found in only two patients among four patients with recurrent acute cholangitis. No patient had recurrent cholangitis caused by MRCP-missed CBD stones. The rates of recurrent cholangitis and cholangitis-free survival did not differ between groups 1 and 2. CONCLUSION: The negative predictive value of MRCP was very high. ERCP can be reserved for patients who are MRCP negative for choledocholithiasis, but close follow-up is needed because of recurrent cholangitis or pancreatico-biliary cancer.

CD40 Agonists Alter the Pancreatic Cancer Microenvironment by Shifting the Macrophage Phenotype toward M1 and Suppress Human Pancreatic Cancer in Organotypic Slice Cultures.

Background/Aims: CD40 agonists are thought to generate antitumor effects on pancreatic cancer via macrophages and T cells. We aimed to investigate the role of CD40 agonists in the differentiation of macrophages and treatment of human pancreatic adenocarcinoma. Methods: Immunohistochemistry was performed on paraffin-embedded surgical blocks from patients with pancreatic cancers to evaluate macrophage phenotypes and their relationship with survival. The effects of CD40 agonists on macrophage phenotypes and human pancreatic cancer were evaluated utilizing cell cocultures and organotypic slice cultures. Results: CD163+ (predominant in M2 macrophages) and FOXP3+ (predominant in regulatory T cells) expression levels in the tumors were significantly lower in patients with stage IB pancreatic cancer than in those with stage II or III disease (p=0.002 and p=0.003, respectively). Patients with high CD163+ expression had shorter overall survival than those with low CD163+ expression (p=0.002). In vitro treatment of THP-1 macrophages with a CD40 agonist led to an increase in HLA-DR+ (predominant in M1 macrophages) and a decrease in CD163+ expression in THP-1 cells. Cell cocultures showed that CD40 agonists facilitate the suppression of PANC-1 human pancreatic cancer cells by THP-1 macrophages. Organotypic slice cultures showed that CD40 agonists alter the pancreatic cancer microenvironment by shifting the macrophage phenotype toward M1 (increase HLA-DR+ and decrease CD163+ expression), decreasing the abundance of regulatory T cells, and increasing tumor cell apoptosis. Conclusions: CD163 is related to advanced human pancreatic cancer stages and shorter overall survival. CD40 agonists alter macrophage phenotype polarization to favor the M1 phenotype and suppress human pancreatic cancer.

Analysis of symptomatic recurrences of common bile ducts stones after endoscopic removal: Factors related to early or multiple recurrences.

ABSTRACT: Early or multiple recurrences of symptomatic common bile duct (CBD) stones are troublesome late complications after endoscopic stone removal. We aimed to determine the factors related to early or multiple recurrences of CBD stones.We retrospectively analyzed patients who underwent endoscopic CBD stone extraction in a single institute between January 2006 and December 2015. Patients were divided into 2 groups according to the number and interval of CBD stone recurrences: single versus multiple (≥2) and early (<1.5 years) versus late (≥1.5 years) recurrence.After exclusion, 78 patients were enrolled and followed up for a median of 1974 (IQR: 938-3239) days. Twenty-seven (34.6%) patients experienced multiple recurrences (≥2 times), and 26 (33.3%) patients experienced early first recurrence (<1.5 years). In the multivariate analysis, CBD angulation was independently related to multiple CBD stone recurrence (OR: 4.689, P = .016), and endoscopic papillary large balloon dilation was independently related to late first CBD stone recurrence (OR: 3.783, P = .025). The mean CBD angles were more angulated with increasing instances of recurrence (0, 1, 2, 3, and ≥4 times) with corresponding values of 150.3°, 148.2°, 143.6°, 142.2°, and 126.7°, respectively (P = .011). The period between the initial treatment and first recurrence was significantly longer than the period between the first and second recurrence (P = .048).In conclusion, greater CBD angulation is associated with the increased number of CBD stone recurrence, and EPLBD delays the recurrence of CBD stones after endoscopic CBD stone removal.

The Safety of Radiofrequency Ablation Using a Novel Temperature-Controlled Probe for the Treatment of Residual Intraductal Lesions after Endoscopic Papillectomy.

BACKGROUND/AIMS: Treatment of residual intraductal lesions after endoscopic papillectomy for ampullary adenomas is relatively difficult. Few studies have been conducted using intraductal radiofrequency ablation (RFA) in the treatment of such lesions, and no study has aimed to reduce the side effects of excessive heat caused by RFA. Recently, a temperature-controlled RFA probe was developed to avoid excessive heat. This study aimed to investigate the safety of this new RFA probe in the treatment of intraductal lesions of ampullary adenoma. METHODS: Patients who received RFA for residual intraductal lesions after endoscopic papillectomy between November 2017 and June 2019 were retrospectively reviewed. A novel temperature- controlled probe (ELRA) was used for intraductal RFA, and clinical data including adverse events were collected. RESULTS: Ten patients were included in this study. Intraductal adenomas showed low-grade dysplasia in eight patients and high-grade dysplasia in two patients. The median diameter of intraductal adenomas was 9 mm (range, 5 to 10 mm) in the common bile duct and 5 mm (range, 4 to 11 mm) in the pancreatic duct. Adverse events occurred in three patients (30.0%), of which two were mild pancreatitis and one was asymptomatic biliary stricture. Over a median follow-up period of 253 days, only one patient underwent additional surgery, as the remainder showed no adenomatous lesions on follow-up biopsies. CONCLUSIONS: The new temperature-controlled RFA probe can be used with acceptable safety for the treatment of residual intraductal lesions after endoscopic papillectomy. Further evaluation through future prospective studies is needed.

Expression of protease activated receptor-2 in human colorectal cancer and its association with tumor progression.

PURPOSE: Protease activated receptor-2 has been reported to promote the proliferation of colorectal cancer cells. The aim of this study was to investigate the relationship of protease activated receptor-2 expression to clinicopathologic factors to clarify its role in tumor progression and patient survival in human colorectal cancer. METHODS: Immunohistochemical staining with anti-protease activated receptor-2 antibody was carried out and evaluated on samples from 295 patients with colorectal cancer obtained during surgical treatment at Kangnam St. Mary's Hospital, Seoul, Republic of Korea. Medical records were reviewed and relationships between immunostaining and clinicopathologic findings were evaluated. RESULTS: Positive staining for protease activated receptor-2 was observed in samples from 100 patients (33.9%). Expression of protease activated receptor-2 was significantly associated with depth of tumor invasion (P = .013), liver metastasis (P = .008), TNM stage (P = .009), and tumor location (P = .011). However, protease activated receptor-2 expression did not significantly correlate with overall survival of patients and was not a significant negative prognostic factor for survival in univariate or multivariate analyses. CONCLUSIONS: The expression of protease activated receptor-2 is related to tumor invasion and metastasis in human colorectal cancer. However, further studies are needed to clarify the role of protease activated receptor-2 in the prognosis of patients with colorectal cancer.

Diagnostic value of the PPI test for detection of GERD in Korean patients and factors associated with PPI responsiveness.

OBJECTIVES: Data supporting the use of the proton pump inhibitor (PPI) test as a diagnostic test of gastroesophageal reflux disease (GERD) in Asia are lacking. The aims of this study were to evaluate the diagnostic characteristics of the PPI test and factors associated with responsiveness to PPIs. METHODS: The PPI test was evaluated using lansoprazole (30 mg bid) for two weeks. All patients underwent endoscopy after symptom assessment. Patients without erosive esophagitis (ERD) underwent 48 h esophageal Bravo pH monitoring. Subjects were considered to be responsive to PPIs if they reported a > 50% reduction in reflux symptom score. RESULTS: Seventy-three patients (M:F = 40:37, 47 +/- 13 years) were enrolled. We identified 46 patients with ERD, 18 patients with nonerosive reflux disease (NERD) and 9 patients without GERD. The PPI response rate was higher in patients with GERD than in patients without GERD (49/64, 77% vs. 4/9, 44%; p < 0.05). The sensitivity, specificity, and positive and negative predictive values were 77%, 56%, 92% and 25%, respectively. The PPI responsiveness was 80% (37/46) in the ERD group and 67% (12/18) in the NERD group. PPI response was not affected by age, sex, Helicobacter pylori, the psychological characteristics or cytochrome P2C genotypes. ERD and symptom-reflux association were the factors affecting PPI responsiveness. CONCLUSIONS: The PPI test was modestly sensitive and specific for diagnosing GERD. However, it would be useful for discriminating patients with ERD. In the NERD group, patients with positive symptom-reflux association would be most benefit from PPI treatment.

Clinical outcomes of self-expandable metal stent and prognostic factors for stent patency in gastric outlet obstruction caused by gastric cancer.

The aim of this study was to assess clinical outcomes of endoscopic stenting for a gastric outlet obstruction caused by gastric cancer and the prognostic factors for stent patency by reviewing medical records. Eighty-one stents were inserted into 75 patients (48 men, average age 66 years). The technical and clinical success rates were 98 and 87%, respectively. The median stent patency was 55 days (95% CI 40-70 days). The median survival was 79 days (95% CI 58-123 days). Stent reobstruction caused by tumor ingrowth or overgrowth occurred in 25 cases (31%). Cox multivariate regression analysis showed that covered stents (odds ratio 0.29, 95% CI 0.11-0.76; P = 0.01) and chemotherapy after stent placement (odds ratio 0.34, 95% CI 0.13-0.91; P = 0.03) were significant prognostic factors for stent patency. This study found that endoscopic stenting is a safe and effective palliation treatment for malignant gastric outlet obstruction and a covered stent and chemotherapy are significant prognostic factors for stent patency.

[Change of Clostridium difficile colitis during recent 10 years in Korea].

BACKGROUND/AIMS: Our clinical experience and recent published literatures suggest that Clostridium difficile colitis (CDC) has become more common and potentially more pathogenic in recent years. The aim of study was to evaluate changes in the epidemiological features of CDC in hospitalized patients in Korea. METHODS: We retrospectively reviewed all patients of CDC diagnosed at Kangnam St. Mary Hospital from 1998 to 2007. CDC was defined as having a positive C. difficile cytotoxicity assay, or endoscopic or pathologic evidence of CDC. RESULTS: A total of 189 cases (male 73, female 116, mean age 63.3 years) of CDC were diagnosed during the study period. The prevalence of CDC increased from 1.9/10,000 patient admissions in 1998-1999 to 8.82/10,000 patient admissions in 2006-2007. One hundred sixty three indication for cases (86.2%) of patients identified a prior use of antibiotics in the 2 months preceding diagnosis. The most common antibiotic use was prophylactic use during perioperational period (33.3%) followed by pneumonia (23.3%). The overall response rate to initial antibiotics was 82.7%. One hundred seventy two (91%) patients were initially treated with metronidazole. The response rate was 84.3%. All patients with initial failure to metronidazole were successfully treated by vancomycin. The response rate of vancomycin as first treatment was 80%. Three deaths were associated with CDC despite the use of combination of metronidazole and vancomycin. CONCLUSIONS: The prevalence of CDC in hospitalized patients in Korea significantly increased from 1998 to 2007.

Prolonged hyperamylasemia in patients with acute pancreatitis is associated with recurrence of acute pancreatitis.

Serum amylase levels in patients with acute pancreatitis often remain or fluctuate above the upper normal limit for over a week. This study investigated the clinical characteristics of patients with prolonged hyperamylasemia and their prognoses, including recurrence.We retrospectively analyzed patients with first attacks of acute pancreatitis in a single center between March 2010 and December 2016. Patients were divided into 2 groups according to normalization of the serum amylase levels within a week.A total of 313 patients were enrolled after exclusion. The serum amylase levels were normalized within a week in 205 patients (65.5%, group 1) and elevated over a week in 108 patients (34.5%, group 2). Group 2 was more related to alcohol, higher computed tomography (CT) severity index, local pancreatic complication, and moderately severe pancreatitis than group 1 (P < .05). Recurrent pancreatitis developed significantly more in group 2 (39.8%) than in group 1 (19.5%) (P < .001). The factors related to recurrent pancreatitis were amylase group, sex, alcohol, CT severity index, necrosis, and severity of pancreatitis (P < .05). Multivariate analysis showed that recurrent pancreatitis was independently associated with amylase group (odds ratio [OR] 2.123, 95% confidence interval [CI]= 1.227-3.673, P = .007) and alcohol (OR 2.023, 95% CI 1.134-3.611, P = .017).In conclusion, prolonged hyperamylasemia over a week is associated with recurrence of acute pancreatitis.