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Considering the significant racial and ethnic diversity in genetic variation, it is unclear whether the genome-wide association studies-identified colorectal cancer (CRC)-susceptibility single-nucleotide polymorphisms (SNPs) discovered in European populations are also relevant to the Korean population. However, studies on CRC-susceptibility SNPs in Koreans are limited.To investigate the racial and ethnic diversity of CRC-susceptibility genetic variants, we genotyped for the established European CRC-susceptibility SNPs in 198 CRC cases and 329 controls in Korea. To identify novel genetic variants using genome-wide screening in Korea, Illumina HumanHap 370K/610K BeadChips were performed on 105 CRC patients, and candidate CRC-susceptibility SNPs were selected. Subsequently, genotyping for replication was done in 189 CRC cases and 190 controls.Among the European CRC-susceptibility SNPs, rs4939827 in SMAD7 was associated with a significant decreased risk of Korean CRC (age-/gender-adjusted odds ratio [95% confidence interval]: additive model, 0.67 [95% CI, 0.47-0.95]; dominant model, 0.59 [95% CI, 0.39-0.91]). rs4779584 and rs10795668 were associated with CRC risk in females and males, respectively. Among candidate CRC-susceptibility SNPs selected from genome-wide screening, novel SNP, rs17051076, was found to be associated with a significantly increased risk of microsatellite instability-high CRC (age-/gender-adjusted odds ratio [95% confidence interval]: additive model, 4.25 [95% CI, 1.51-11.98]; dominant model, 3.52 [95% CI, 1.13-10.94]) in the replication study.rs4939827, rs4779584, and rs10795668 may contribute to the risk of CRC in the Korean population as well as in European populations. Novel rs17051076 could be associated with microsatellite instability-high CRC in Koreans. These associations support the ethnic diversity of CRC-susceptibility SNPs and should be taken into account in large-scale studies.

Objectives There is sparse data on apoB dyslipoproteinemia in Asian population. The purpose of this study was to assess apoB dyslipoproteinemia and to compare the LDL-C, non-HDL and apoB for risk assessment with percentile equivalent cut off in Korean population. Methods With 1193 Korean adult subjects, the prevalence and characteristics of different types of dyslipoproteinemias were analyzed in each age and gender group. The percentile values of direct LDL-C, calculated LDL-C, non HDL-C, HDL-C, apoAI, apoB and apoB/apoAI ratio were estimated. Results The prevalences of normoapoB–hyperTG, hyperapoB–normoTG and hyperapoB–hyperTG dyslipoproteinemia were 6.9, 8.9 and 10.9% in men and 3.7, 6.4 and 2.8% in women. The 40th percentile of direct LDL-C, calculated LDL-C, non-HDL-C and apo B were 108, 104.2, 126 and 85 mg/dl, respectively. The individual above optimal cut off was significantly underestimated with LDL-C than with non-HDL and apoB, in groups with adverse risk factors. Conclusions This study firstly shows the prevalence of various types of dyslipoproteinemias in Asian population. The percentile values of Korean population were similar to those of NHANES. Integration of lipid markers is needed for making clinical decisions and further research involving various populations and methodologies should be performed.

Colorectal cancer (CRC) develops through a polyp-to-cancer progression sequence, in which normal colorectal epithelium transforms into an adenoma, which then progresses to cancer via the accumulation of progressive molecular changes, including both genetic and epigenetic alterations. Given that Colon epithelial cells can acquire pro-tumorigenic mutations that are insufficient to cause morphological change, genetic alternations in adjacent tumor tissues are primed to become neoplastic cells. It is known that individuals with a personal history of colon adenomas or cancer are at increased risk for metachronous colon neoplasms. To examine the genetic alternations involving in a polyp-to-cancer progression sequence, whole-transcriptome expression profiling of resected normal tissues (N1 and N3), adenoma (A1 and A2), and colorectal cancer (C1) obtained from individuals was performed. Differentially expressed genes among groups were identified using Subio platform. GATK and haplotypecaller was used to compare the somatic mutations among three different tissues. Tophat, Cufflink, Mev, R was used for determining the expression levels. Splicegrapher and Genomon-fusion was used for identifying the fusion genes. Ordinal regression analysis was performed to characterize site-dependent expression profiles. Gene interaction was examined using String (Open database). All statistical tests were two-sided, except where noted. Expression profile showed that highly expressed genes associated with inflammation were detected in adenoma. Our results indicated that highly expressed genes associated with inflammation were initially found in adenoma tissues and its levels were consistent in carcinoma tissues. Number of somatic mutation was extremely increased in carcinoma tissues when compared to adenoma tissues. The same mutations in KRAS, CDKN2A(p16) and TP53 that were observed in carcinoma tissues. They were also present in normal tissues and adenoma tissues. Disruption of TP53, CDKN2A, and KRAS were all seen as possible initial events in tumorigenesis; the sequence of mutations (the tumor development pathway) differed among lesions. Also, unique somatic mutations were found 17 genes which were not exist in normal tissues. Those somatic mutations were found in carcinoma tissues. The results of fusion gene analysis showed that 9 fusion genes were detected. Four fusion genes (FIIR-RBM2292, ST7-AS1-ST7, MMP11-IGLL5, EXOC4-LOC101928861) was detected in all of tissues. Five fusion genes were found in normal tissues and adenoma tissues. Unique fusion gene in carcinoma tissue was not detected. One explanation for this increased risk could be field cancerization, which is a phenomenon in which the histologically normal tissue in an organ is primed to undergo transformation. Our analysis of genetic alterations in a single patient appears to be promising markers for field cancerization. Citation Format: Chansu Lee, Sung Noh Hong, Sungjin Kim, Sunghoon Cho, Sohyun Youn, Kwang-Sung Ahn, Young-Ho Kim. Analysis of genetic alternations in multiple tissue specimens from each patient: Implications for field-effect colon cancerization. [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 539.

The prognosis of early-onset sporadic colorectal cancer (CRC) patients remains controversial. The objective of this study was to assess the long-term outcome and prognostic factors of sporadic CRC in young patients. From 2006 to 2011, 8207 patients underwent curative or palliative surgery for CRCs in our institution. A total of 693 patients who were ≤45 years old with sporadic CRC were enrolled as the young group. A total of 1823 patients aged between 56 and 65 years were identified as middle-aged control group for this study. Survival outcome and prognostic factors were compared between the two groups. Young patients had higher recurrence rate than older patients in stages I and II (8.8% vs 2.7%, P

Enteropathy-associated T-cell lymphoma (EATL) is a rare extranodal T-cell lymphoma arising from the intestine. Two types of EATL have been reported. In contrast to the classic EATL type I, EATL type II occurs sporadically, is unrelated to celiac disease, and comprises 10% to 20 % of all EATL cases. A total of five cases of EATL type II were diagnosed at our clinic from January 2009 to September 2012. Four of the five patients were diagnosed with the help of endoscopy. Among the four patients, two of the cases involved both the small and large intestines, whereas in the other two patients, EATL was limited to the small intestine. Common endoscopic findings included innumerable fine granularities (also called mosaic mucosal patterns) and diffuse thickening of the mucosa with a semicircular shallow ulceration in the lesions of the small bowel. In contrast, the endoscopic findings of the colon were nonspecific and could not distinguish EATL type II from other diseases. There are only few published reports regarding the representative endoscopic findings of EATL. Here, we present the clinical and endoscopic findings of four cases of EATL type II diagnosed by endoscopy.

To investigate the association between mucosal color change and the characteristics of early gastric cancer (EGC).Data of consecutive patients with EGC resected between August 2005 and October 2010 at Konkuk University Medical Center were analyzed retrospectively. The characteristics of EGC relative to mucosal color change were analyzed.Whitish discoloration of the cancer was linked to female to male gender ratio (P = 0.009), large tumor size (P 0.001), deep invasion (P = 0.046) and depressed contours (P 0.001) compared with EGC without discoloration or with hyperemic change. In addition, a whitish discoloration was also related to signet ring cell carcinoma (P 0.001) and diffuse type carcinoma based on Lauren's classification (P 0.001). On multiple linear regression analysis, diffuse type based on Lauren's classification (P = 0.017) and depth of invasion (P = 0.003) were significant independent factors for whitish discoloration.Mucosal color change is an important clue in the diagnosis of EGC. EGC with whitish discoloration needs more attention due to its link with the diffuse type of Lauren's classification.

BACKGROUND/AIMS There is a paucity of national guideline for colorectal cancer screening and polyp diagnosis in Korea. Thus, we investigated the present state of colorectal cancer screening and polyp diagnosis methods using web-based survey to use as reference data for developing a guideline. METHODS A multiple choice questionnaires of screening recommendations was sent via e-mail to members of the Korean Association for the Study of Intestinal Diseases and primary care physicians who participated in the national colonoscopy surveillance program. Among 425 colonoscopists, a total 263 colonoscopists replied (response rate, 61.9%). RESULTS The most commonly recommended starting age for colorectal cancer screening and polyp diagnosis was 50 years old in the average risk group, and 40 years old in groups who had a family history of colon cancer (64.3% and 65.0% respectively). Surgeons had a tendency to recommend screening in younger people than internist do. Ninety-eight percent of physicians recommended screening colonoscopy to asymptomatic, average-risk patients as a first choice. Only 2% of physicians chose sigmoidoscopy as a screening tool. When the initial colonoscopy showed a negative finding, over 60% of internists repeated the exam 5 years later, whereas 62% of surgeons did so within 3 years. CONCLUSIONS The starting age of colorectal cancer screening and the interval of the colorectal polyp examination are not uniform in various medical environments, and there is a discrepancy between the practical recommendations and western guidelines. Thus, a new evidence-based national practice guideline for colorectal cancer screening and polyp diagnosis should be developed.

Little is known about non-cardiac chest pain (NCCP) in young patients. We aimed to examine the proportion of gastroesophageal reflux disease (GERD) in young patients with NCCP compared to the average-aged NCCP patients and to evaluate their symptomatic characteristics and the clinical efficacy of a 2-week proton pump inhibitor (PPI) trial.Ninety-six patients with NCCP≥1/week were classified into the young-aged (≤ 40 years, n =38) and the average-aged groups (40 years, n=58). Typical reflux symptoms were assessed. The patients were defined into a GERD group and non-GERD group according to reflux esophagitis on esophagogastroduodenoscopy and/or pathologic acid exposure on 24-h esophageal pH monitoring. Then the patients were treated with 30mg of lansoprazole bid for 14 days.Nine patients (23%) in the young-aged group and 22 patients (38%) in average-aged group were diagnosed with GERD-related NCCP (P=0.144). The proportion of typical reflux symptoms was higher in the GERD group compared with the non-GERD group in both age groups. A PPI test improved symptoms in the GERD group irrespective of age, but this improvement was not observed in non-GERD group.In young NCCP patients, the prevalence of GERD was relatively low compared to average-aged NCCP, but the difference was insignificant. The PPI test was very effective in diagnosing GERD in the NCCP patients in both age groups. Therefore, in young NCCP patients, if there is a negative response to a 2-week PPI trial, the possibility of extra-esophageal disease origin needs to be considered.

Now colorectal cancer is the second most common cancer in males and the fourth most common cancer in females in Korea. Since most of colorectal cancers occur after the prolonged transformation of adenomas into carcinomas, early detection and removal of colorectal adenomas are one of the most effective methods to prevent colorectal cancer. Considering the increasing incidence of colorectal cancer and polyps in Korea, it is very important to establish Korean guideline for colorectal cancer screening and polyp detection. The guideline was developed by the Korean Multi-Society Take Force and we tried to establish the guideline by evidence-based methods. Parts of the statements were draw by systematic reviews and meta-analyses. Herein we discussed epidemiology of colorectal cancers and adenomas in Korea and optimal methods for screening of colorectal cancer and detection of adenomas including fecal occult blood tests, radiologic tests, and endoscopic examinations.

There are indirect evidences to suggest that 80% of colorectal cancers (CRC) develop from adenomatous polyps and that, on average, it takes 10 years for a small polyp to transform into invasive CRC. In multiple cohort studies, colonoscopic polypectomy has been shown to significantly reduce the expected incidence of CRC by 76% to 90%. Colonoscopic polypectomy is performed frequently in primary, secondary and tertiary and medical centers in Korea. However, there are no evidence-based, procedural guidelines for the appropriate performance of this procedure, including the technical aspects. For the guideline presented here, Pubmed, Medline, and Cochrane Library literature searches were performed. When little or no data from well-designed prospective trials were available, an emphasis was placed on the results from large series and reports from recognized experts. Thus, these guidelines for colonoscopic polypectomy are based on a critical review of the available data as well as expert consensus. Further controlled clinical studies are needed to clarify aspects of this statement, and revision may be necessary as new data become available. This guideline is intended to be an educational device to provide information that may assist endoscopists in providing care to patients. This guideline is not a rule and should not be construed as a legal standard of care or as encouraging, advocating, requiring, or discouraging any particular treatment. Clinical decisions for any particular case involve a complex analysis of the patient's condition and the available courses of action.

Endoscopic submucosal dissection (ESD) for colorectal neoplasms is not widely performed because of the high risk of perforation. Perforations are divided into macroperforations and microperforations. Currently, there is a limited amount of clinical data on the outcome of patients with these types of perforations during colonic ESD. The aim of this study was to investigate the clinical outcome of patients who sustained colon perforations during ESD. We also compared the clinical outcome of patients with microperforations and those with macroperforations. This study enrolled 101 patients with colorectal laterally spreading tumors (LST) who underwent ESD. We retrospectively reviewed their medical records, including patient demographic data and the clinical, endoscopic, and pathologic features. In the cases where perforation had occurred, the course of hospital treatment was analyzed. All ESD-related perforations were divided into macroperforations and microperforations. A macroperforation was defined as a gross perforation that occurred during an ESD procedure and a microperforation was defined by free air visible on X-rays after the procedure. Of the 101 enrolled patients, 9 (8.9 %) developed perforations. The most common tumor morphology was nongranular-type LST (5 of 9 cases, 55.6 %) based on endoscopic examination. Five patients had microperforations and four had macroperforations. All macroperforations were closed primarily by endoclips during ESD. The endoscopic characteristics did not differ between the groups. However, the length of hospital stay and the mean duration of NPO and antibiotic treatments were longer for microperforation patients. All patients had conservative nonsurgical management such as fasting, intravenous antibiotics, and nasogastric tube drainage. The clinical complications for microperforation patients were worse than those for macroperforation patients. However, the clinical prognoses of patients with perforations that occur during colonic ESD are favorable.

Background/Aims Although a small amount of fecal material can obscure significant colorectal lesions, it has not been well documented whether bowel preparation status affects the missing risk of colorectal polyps and adenomas during a colonoscopy. Methods We prospectively enrolled patients with one to nine colorectal polyps and at least one adenoma of >5 mm in size at the screening colonoscopy. Tandem colonoscopy with polypectomy was carried out within 3 months. Results A total of 277 patients with 942 polyps and 714 adenomas completed index and tandem examinations. At the index colonoscopy, 187 polyps (19.9%) and 127 adenomas (17.8%) were missed. The per-patient miss rate of polyps and adenomas increased significantly as the bowel cleansing rate declined from excellent to poor/inadequate on the Aronchick scale (polyps, p=0.024; adenomas, p=0.040). The patients with poor/inadequate bowel preparation were independently associated with an increased risk of having missed polyps (odds ratio [OR], 3.21; 95% confidence interval [CI], 1.13 to 9.15) or missed adenomas (OR, 3.04; 95% CI, 1.04 to 8.88) compared to the patients with excellent bowel preparation. Conclusions The risk of missing polyps and adenomas during screening colonoscopy is significantly affected by bowel preparation status. It seems appropriate to shorten the colonoscopy follow-up interval for patients with suboptimal bowel preparation.

Surveillance is becoming common in the practice of colonoscopy because a large number of patients with colorectal polyps are now being discovered as a result of the increased use of colorectal cancer screening, and particularly because of the dramatic increase in screening colonoscopy. Although the term ‘colorectal polyp’ is not synonymous with colorectal adenoma, two-thirds of colorectal polyps are adenomas and most colorectal cancers arise from them. Therefore, removal of colorectal polyps using colonoscopic polypectomy has been shown to reduce the risk of future colorectal cancer (Winawer et al., 1993; Atkin et al., 2010). A patient with one colorectal adenoma has a 30 to 50% likelihood of harboring a second synchronous adenoma elsewhere in the colon and rectum at that time, and they have a 3050% likelihood of developing metachronous adenoma sometime in the future (Winawer et al., 2006; Arditi et al., 2009). Therefore, to minimize the risk for colorectal cancer in the future, patients with adenomas are usually placed into a post-polypectomy surveillance program. Post-polypectomy surveillance refers to periodically examining the colon to detect and remove missed synchronous and new metachronous adenomas and cancers, by screening or other means, after the detection and removal of a precancerous lesion. Generally, it does not refer to the use of colonoscopy or other procedures to monitor for polyp or cancer recurrence following a diagnosis of colorectal cancer. This chapter reviews the rationale, the recent literature and the current recommendations for post-polypectomy surveillance, with emphasizing the need to tailor surveillance strategies to the carefully considered individualized assessment of the risk factors as related to the characteristics of the baseline adenoma and those of the individual patient.

Background The newly developed i-SCAN application can theoretically maximize the effectiveness of colonoscopy. However, the practical usefulness of the i-SCAN application during screening colonoscopy has not been assessed. Objective To assess the efficacy of the i-SCAN application during screening colonoscopy. Design A prospective, randomized trial that used a modified, back-to-back colonoscopy. Setting Academic hospital. Patients This study involved 389 asymptomatic, consecutive, average-risk patients who underwent screening colonoscopy. Intervention The patients were randomized to the first withdrawal with either conventional high-definition white light (HDWL group; n=119), i-SCAN contrast/surface enhancement (CE/SE) mode (i-SCAN1 group; n=115), or i-SCAN CE/SE/tone enhancement-colorectal mode (i-SCAN2 group; n=118). All patients underwent a second examination with HDWL as the criterion standard. Main Outcome Measurements The primary outcome measurement was the adenoma detection rate and adenoma miss rate. The secondary outcome measurement was the accuracy of the histologic prediction of neoplastic and nonneoplastic polyps. Results The adenoma detection rates during the first withdrawal of HDWL, i-SCAN1, and i-SCAN2 were 31.9%, 36.5%, and 33.1%, respectively ( P = .742), and the adenoma miss rates of each group were 22.9%, 19.3%, and 15.9%, respectively ( P = .513). Based on the multivariate analysis, the application of i-SCAN was not associated with an improvement in adenoma detection and the prevention of missed polyps. However, the prediction of neoplastic and nonneoplastic colorectal lesions was more precise in the i-SCAN2 group compared with the HDWL group (accuracy 79.3% vs 75.5%, P = .029; sensitivity 86.5% vs 72.6%, P = .020; and specificity 91.4% vs 80.6%, P = .040). Limitations Single-center trial. Conclusion i-SCAN during the screening colonoscopy may fail to improve adenoma detection and the prevention of missed polyps, but i-SCAN appears to be effective for real-time histologic prediction of polyps compared with conventional HDWL colonoscopy. (Clinical trial registration number: NCT01417611.)

AIM: To determine whether gastrointestinal (GI) symptoms are more frequent in type 2 diabetic patients and to examine which diabetic factors are associated with the symptoms. METHODS: Consecutive subjects with diabetes and age-/gender-matched normal controls were recruited for this study. GI symptoms were assessed using a structured questionnaire divided into two GI symptom categories (upper and lower GI symptoms), and consisting of 11 individual symptoms. In the diabetic patient group, diabetic complications including peripheral neuropathy, nephropathy and retinopathy, glycosylated hemoglobin (HbA1c) level and diabetes duration were evaluated. RESULTS: Among the total 190 diabetic patients and 190 controls enrolled, 137 (72%) of the diabetic patients and 116 (62%) of the controls had GI symptoms. In the diabetic patient group, 83 (43%) had upper GI symptoms and 110 (58%) lower GI symptoms; in the control group, 59 (31%) had upper GI symptoms and 104 (55%) lower GI symptoms. This difference between the two groups was significant for only the upper GI symptoms (P = 0.02). Among the diabetic factors, the HbA1c level was the only independent risk factor for upper GI symptoms in the multiple logistic regression analysis (odds ratio = 2.01, 95% confidence interval: 1.02-3.95). CONCLUSION: Type 2 diabetes was associated with an increased prevalence of upper GI symptoms and these symptoms appeared to be independently linked to poor glycemic control, as measured by the HbA1c levels.

Background/aims Noncardiac chest pain (NCCP) is a very common disorder world-wide and gastroesophageal reflux disease (GERD) is known to be the most common cause. The prevalence of NCCP may tend to decrease with increasing age. However, there is little report about young aged NCCP. The aim of this study was to examine the prevalence of GERD and to evaluate the efficacy of proton pump inhibitor (PPI) test in the young NCCP patients. Methods Thirty patients with at least weekly NCCP less than 40 years were enrolled. The baseline symptoms were assessed using a daily symptom diary for 14 days. Esophago-gastro-duodenoscopy (EGD) and 24 hr esophageal pH monitoring were performed for the diagnosis of GERD and esophageal manometry was done. Then, patients were tried with lansoprazole 30 mg twice daily for 14 days, considering positive if a symptom score improved >/= 50% compared to the baseline. Results Nine (30%) of the patients were diagnosed with GERD at EGD and/or 24 hr esophageal pH monitoring, also, 3 (10%) were diagnosed with GERD-associated esophageal motility disorder and 3 (10%) were non GERD-associated. Concerning PPI test, GERD-related NCCP had a higher positive PPI test (n = 8, 89%) than non GERD-related NCCP (n = 5, 24%) (p = 0.002). Conclusions In young patients with NCCP, a prevalence of GERD diagnosed using EGD and/or 24 hr esophageal pH monitoring was 30%. PPI test was very predictable on diagnosis of GERD-related NCCP, thus, PPI test in young NCCP patients may assist to the physician's clinical judgment of NCCP.

Maspin is expressed aberrantly in pancreatic ductal adenocarcinoma (PDAC), and its function is still unknown. To explore the role of maspin in PDAC, we constructed wild-type maspin-expressing Panc-1 clones (Panc-1-maspin) by transfecting maspin cDNA into Panc-1, a PDAC-derived cell line that lacks maspin expression. As a control, mock-transfected clones (Panc-1-mock) were constructed using the same method. The invasive ability of the stable transfectants was evaluated with an in vitro invasion assay. The ability of Panc-1-maspin cells to migrate through a Matrigel-coated filter was significantly reduced compared to that of Panc-1-mock cells (p=0.012). In addition, we identified the c.1022A>G variant of maspin in human PDAC cells; however, this polymorphism was not involved in the clinical characteristics of PDAC nor did it alter the invasive ability of PDAC cells. The results of the present study indicate that maspin suppresses the invasive ability of PDAC cells.

Background/Aims: Colorectal adenomas that are ≥10 mm have villous histology or high-grade dysplasia, or that are associated with ≥3 adenomas are considered high-risk for metachronous advanced neoplasia. We evaluated the cumulative incidence of metachronous advanced neoplasia according to the total number of high-risk findings detected on baseline colonoscopy. Methods: This was a retrospec- tive cohort study performed in 862 patients who underwent removal of colorectal adenomas between 2005 and 2009. At least one surveillance colonoscopy had been conducted at Konkuk University Medical Center, Seoul, Korea. Results: The cumulative incidence of metachronous advanced neo- plasia in patients with 0, 1, 2, and 3-4 high-risk findings at 1 year were 0.7%, 1.3%, 2.8%, and 8.0%; at 3 years, those were 5.9%, 11.9%, 15.5%, and 24.7%; and at 5 years, those were 8.5%, 18.7%, 26.3%, and 37.2%, respectively. In a mul- tivariate model, the risk of metachronous advanced neopla- sia was significantly higher for the multiple high-risk findings group when compared with the 0 high-risk findings group (1 high-risk (+): hazard ratio, 1.86 (95% confidence interval, 1.00-3.44); 2 high-risk (+): 1.84 (0.88-3.84); and 3-4 high- risk (+): 3.29 (1.54-7.01); ptrend=0.020). Conclusions: The presence of overlapping multiple high-risk findings was asso- ciated with an increased risk of advanced neoplasia during surveillance. (Gut Liver 2015;9:741-749)

major immediate and delayed bleeding per tumor were 1% and 2.2%. Need for emergency surgery was reported in 17 cases mainly due to perforation and severe bleeding. Procedure-related mortality rate was 0%. After an average follow up of 22.9 11.5 months, overall recurrence rate was 1.1%, and 0.1% after en bloc resection.. Conclusion: Given the safety and efficacy of colorectal ESD in this meta-analysis, development of systematic training programs to promote safe adoption is warranted.

Cholecystectomy is associated with an increased risk of colorectal cancer, but little is known about the relationship between gallbladder disease and colorectal adenoma. Gallbladder polyps and colorectal neoplasia (CRN) share several risk factors such as obesity, diabetes and metabolic syndrome, which might account for their association. In this study, we investigated whether asymptomatic patients with gallbladder disease are at increased risk of CRN and identified the factors to their association. The study population consisted of 4,626 consecutive, asymptomatic individuals drawn from a prospective health check-up cohort who underwent both ultrasonography and colonoscopy screening. The prevalence of CRNs in patients with gallbladder polyps or gallstones was significantly higher than that in the control group (32.1% vs. 26.8%; P = 0.032, 35.8% vs. 26.9%; P = 0.020). A multivariate regression analysis showed that gallbladder polyps were an independent risk factor for CRN [adjusted odds ratio (OR): 1.29; 95% confidence interval (CI); 1.03-1.62] whereas gallstones were not (adjusted OR: 1.14; 95% CI: 0.79-1.63). The adjusted OR for the risk of CRN was 1.12 for gallbladder polyps < 5 mm (95% CI, 0.85-1.46) and 1.79 for gallbladder polyps ≥ 5 mm (95% CI, 1.15-2.77). The prevalence of CRN increased with increasing polyp size (P trend = 0.022). Our results suggest that colorectal neoplasia is significantly related to gallbladder polyps, especially those ≥ 5 mm. Graphical Abstract

A significant proportion of chronic constipation patients are dissatisfied with their treatment. Recently, a number of new medicationshave been introduced for patients refractory to conventional laxatives, such as prucalopride, lubiprostone, linaclotide, andelobixibat. Prucalopride is a novel gastrointestinal prokinetic agent that acts as a 5-hydroxytryptamine type 4 (5-HT4) agonist. Compared with older nonselective 5-HT4 agonists, the higher selectivity of prucalopride for 5-HT4 receptors can reduce the risk ofsignificant adverse cardiovascular events. Prucalopride improves stool frequency and consistency, and reduces the need for rescuemedications. Lubiprostone, a chloride channel activator, increases the secretion of intestinal fluid, improves the stool frequency andconsistency, and reduces straining. Linaclotide, a guanylate cyclase-C agonist, is effective in treating patients with chronic constipationand its effect on visceral sensitivity, as shown mainly in animal studies, provides an attractive pharmaceutical option for patients with irritable bowel syndrome with constipation. Elobixibat is an ileal sodium-dependent bile acid transporter inhibitor thatblocks the enterohepatic circulation of bile acids, increasing the bile acid concentration in the intestine, which accelerates colonictransit and softens the stool. A phase III trial of the treatment of chronic constipation and irritable bowel syndrome with constipationis underway. The clinical application of new-generation laxatives will contribute to the management of chronic constipation refractoryto conventional laxatives.

To manage chronic constipation, dietary and lifestyle modifications should be tried before pharmacological intervention. Although there is no standardized treatment guideline for medical practice, the key considerations in the choice of laxative includethe treatment duration, dosing schedule, type of agent, effects and side effects of the agent, and cost. The first-line treatment is abulking or osmotic laxative. If the patient is still symptomatic, the physician can add or switch to other laxatives. Next, prucalopride,a highly selective 5-hydroxytryptamine 4 (5-HT4) receptor agonist, could be considered. If the constipation is refractory tocombination therapy with conventional laxatives and prucalopride, patients should be referred for further evaluation, includingphysiological testing.

To compare the efficacy of radiofrequency ablation (RFA) and surgical resection in a group of patients with a Child-Pugh score of 5 and a single HCC less than 4 cm in diameter.Radiofrequency ablation (RFA) has become a popular method for treatment of hepatocellular carcinoma (HCC) and has been applied as an alternative primary therapy to surgical resection.We compared outcomes for 148 patients treated with RFA (n = 55) and those treated surgically (n = 93).The rate of local recurrence among patients in the RFA group was significantly higher than in the surgery group (P = 0.005), while the incidence of remote recurrence was similar between the two groups (P = 0.30). The cumulative 1- and 3-year overall survival rates (P = 0.24) and the cumulative 1- and 3-year recurrence-free survival rates (P = 0.54) were not significantly different between the two groups.Despite a higher rate of local recurrence, RFA was found to be as effective as surgical resection for the treatment of single small HCC in patients with well-preserved liver function, in terms of the incidence of remote recurrence and the patients' likelihood of achieving overall and/or recurrence-free survival.

In cirrhotic patients with esophageal variceal bleeding, bacterial infections are a frequent complication. Oral antibiotic prophylaxis decreases the incidence of bacterial infections. The administration of oral antibiotics, however, may be difficult in some cirrhotic patients with active bleeding. The purpose of this study was to assess the efficacy of prophylactic intravenous antibiotics for the prevention of bacterial infections in cirrhotic patients with esophageal variceal bleeding.From December 1998 to September 2001, a total of 40 consecutive cirrhotic patients with Child-Pugh class B or C were enrolled after emergent endoscopic esophageal variceal ligation (EVL) was taken because of esophageal variceal bleeding. Enrolled patients were randomized into a treatment group and a control group. The treatment group (n=20) received the intravenous ciprofloxacin 200mg IV q 12 hours for 3 days while the control group(n=20) didn,t.Bacterial infection developed in nine patients (45%) of the control group and only two patients (10%) in the treatment group. The incidence of bacterial infections was significantly lower in the treatment group than the control group (p0.005). The hospital cost and length of hospital stay decreased in the treatment group compared with the control group (p0.001). There were no differences in the hospital course and mortality within 30 days between the two groups.In cirrhotic patients with variceal bleeding and with Child-Pugh class B or C, the use of intravenous ciprofloxacin for 3 days after EVL was not only effective in the prevention of bacterial infections but also cost-effective.

Irritable bowel syndrome (IBS) is the most prevalent functional gastrointestinal disorder. It is a multifactorial disorder. Intestinal microbiota may cause the pathogenesis of IBS by contributing to abnormal gastrointestinal motility, low-grade inflammation, visceral hypersensitivity, communication in the gut-brain axis, and so on. Previous attempts to identify the intestinal microbiota composition in IBS patients have yielded inconsistent and occasionally contradictory results. This inconsistency may be due to the differences in the molecular techniques employed, the sample collection and handling methods, use of single samples that are not linked to fluctuating symptoms, or other factors such as patients’ diets and phenotypic characterizations. Despite these difficulties, previous studies found that the intestinal microbiota in some IBS patients was completely different from that in healthy controls, and there does appear to be a consistent theme of Firmicutes enrichment and reduced abundance of Bacteroides. Based on the differences in intestinal microbiota composition, many studies have addressed the roles of microbiota-targeted treatments, such as antibiotics and probiotics, in alleviating certain symptoms of IBS. This review summarizes the current knowledge of the associations between intestinal microbiota and IBS as well as the possible modes of action of intestinal microbiota in the pathogenesis of IBS. Improving the current level of understanding of host-microbiota interactions in IBS is important not only for determining the role of intestinal microbiota in IBS pathogenesis but also for therapeutic modulation of the microbiota.

Background/aims Helicobacter pylori infection is linked to the development of gastric cancer. H. pylori-associated gastric inflammation is considered to be the first important step in the histogenesis of such neoplasia. However, studies that compare proteome of gastric mucosa infected with or without H. pylori are lacking. Methods We employed proteomics analysis on the endoscopic biopsy specimens of gastric mucosa obtained from two groups (30 cases): healthy subjects without H. pylori infection (15 cases), and gastritis patients with H. pylori infection (15 cases). The pooled proteins obtained from gastric mucosa infected with or without H. pylori were separated by two-dimensional gel electrophoresis and analyzed by a computer-aided program. The altered protein expressions were then identified by mass spectrometry and validated by Western blotting and immunohistochemistry. Results On mass spectrometry using MALDI TOF™ Analyzer, the up-regulation of Keratin 1, ezrin, adenosine triphosphate (ATP) synthase subunit alpha mitochondrial isoform c, Keratin type I cytoskeletal 19, and Keratin type I cytoskeletal 9 were identified; in contrast, 71 kd heat shock cognate protein, ATP synthase subunit alpha mitochondrial precursor, and annexin IV were down-regulated. Among them, membrane cytoskeleton linker ezrin was validated using Western blot and immunohistochemistry. Conclusions Expression of ezrin was significantly different between the gastric mucosa with and without H. pylori infection. Therefore, ezrin could be considered a promising potential molecular marker for detecting H. pylori infection in gastric mucosa.

Background/Aims: Crohn’s disease is a chronic inflammatory bowel disease. Stricture is a very important indication for surgical intervention as strictures can lead to intestinal obstruction. Strictures can be divided into inflammatory and fibrous strictures. Intestinal obstruction due to inflammatory stricture is expected to be resolved with medical treatment. However, factors that can predict the response to medical treatments are unknown. In the present study, we aimed to identify the factors that can predict the response to medical treatments in Crohn’s disease patients with intestinal obstruction. Methods: Data were collected by retrospectively reviewing the medical records of patients with Crohn’s disease who visited the emergency department at Samsung Medical Center in Seoul from January 1, 2000 to December 31, 2010 because of intestinal obstruction. Based on the response to medical treatments, we classified the patients as responders and non-responders and compared the clinical, biochemical, and radiological findings of the two groups. Results: A total of 39 patients were enrolled. Twenty-nine patients responded to medical treatments whereas 10 patients did not. Significant differences were observed between the two groups in terms of vomiting and duration of disease before the development of obstruction. Conclusions: Patients who responded to the medical treatments exhibited a higher incidence of vomiting and longer duration of disease before the development of obstruction. However, further prospective studies are needed to identify the factors that can predict the response to medical treatments. (Korean J Gastroenterol 2013;62:213-218)

Background/Aims Improvements in the endoscopic evaluation and management of gastric cancer have made it possible to determine the depth of invasion during endoscopic examination. The aim of this study was to elucidate the differences between early gastric cancer (EGC) that resembles advanced gastric cancer (AGC) and AGC that resembles EGC. Methods We retrieved cases of EGC-like AGC and AGC-like EGC from consecutive gastric cancers that had been completely resected. The endoscopic diagnoses and clinicopathological findings were analyzed. Results AGC-like EGCs were located mainly in the distal part of the stomach, whereas EGC-like AGCs were located mainly in the proximal part of the stomach (p

Technological Assistance of Cap-Assisted Chromoendoscopy Enhances the Detection Rates of Both Colorectal Adenoma and Proximal Serrated Polyp in an Average-Risk Screening Population: Preliminary Results of a Multi-Center Randomized Controlled Trial Hyun-Soo Kim*, Hong Jun Park, Chan Sik Won, Hyo Keun Jeon, Dongil Park, Jae Myung Cha, Seun-Ja Park, Hwang Choi, Jeong Eun Shin, Chang Soo Eun, Jin-Oh Kim, Hyun Gun Kim, Seong-Eun Kim, Cheol Hee Park, Tae Il Kim, Sung Noh Hong, Dong-Hoon Yang, Byung Chang Kim, Byungho Nam Yonsei Univ. Wonju College of Medicine, Wonju, Republic of Korea; Sungkyunkwan University College of Medicine, Seoul, Republic of Korea; KyungHee University College of Medicine, Hanam, Republic of Korea; Kosin University College of Medicine, Busan, Republic of Korea; The Catholic University of Korea College of Medicine, Incheon, Republic of Korea; Dankook University College of Medicine, Cheonan, Republic of Korea; Hanyang University College of Medicine, Guri, Republic of Korea; Soonchunhyang University College of Medicine, Seoul, Republic of Korea; Ewha Womans University School of Medicine, Seoul, Republic of Korea; Hallym University College of Medicine, Anyang, Republic of Korea; Yonsei University College of Medicine, Seoul, Republic of Korea; Konkuk University School of Medicine, Seoul, Republic of Korea; University of Ulsan College of Medicine, Seoul, Republic of Korea; National Cancer Center, Goyang, Republic of Korea Background/Aim: There is growing evidence that a transparent cap or chromoendoscopy improve detection of colorectal polyps. However, the combined method of these two technologies has not been proven for colorectal polyp or adenoma detection rate. In this multicenter prospective randomized trial, we examined whether cap-assisted chromoendoscopy (CAP-ACE) enhances colorectal adenoma detection rate especially in the proximal colon. Methods: From March 2010 to October 2011, 1,202 asymptomatic average-risk subjects who underwent the first screening colonoscopy in an age of 45 to 75 were enrolled at 14 hospitals. Eighteen expert colonoscopists (more than 5,000 procedures) have performed procedures. Subjects were randomly allocated to CAP-ACE group and regular colonoscopy (RC) group. We prospectively compared insertion and withdrawal time, polyp detection rate (PDR), adenoma detection rate (ADR), and proximal serrated polyp detection rate (PSPDR) between the two groups. Results: A total of 1,202 subjects were enrolled; 598 CAP-ACEs and 604 RCs were performed. Overall PDR and ADR were 60.3% and 47.6%. A total of 52 advanced lesions were found including 16 tubulovillous adenomas, 2 villous adenomas, 13 high grade dysplasias, 11 intramucosal cancers and 10 invasive cancers. The time to cecal intubation (4.8 vs. 4.8 min, p 0.902) was not different between the groups but withdrawal time was prolonged in CAP-ACE group for indigocarmine solution spray and suction (10.5 vs. 8.7 min, p 0.001). Compared to RC, CAP-ACE did increase PDR (65.9% vs. 54.8%, p 0.001) and ADR (51.8% vs. 45.5%, p 0.033) significantly. In particular, this technological assistance of CAP-ACE even in experts significantly enhanced the proximal adenoma detection rate (34.8% vs. 28.8%, p 0.030) as well as PSPDR (10.5% vs. 6.1%, p 0.006). However, advanced lesions (CAPACE 26/598 (4.3%) vs. RC 26/604 (4.3%), p 0.99) including cancers were equally found between groups. Conclusion: Technological assistance of CAP-ACE enhances not only PDR but also ADR, especially in the proximal colon. These results suggest that CAP-ACE technology provide a potential solution for overcoming the limited effectiveness of colonoscopy in the proximal colon and should be considered as the preferred, high standard colorectal cancer screening method for the average-risk screening population.

Background/Aims: Gastric atrophy can be diagnosed by serum pesinogen I/II ratio. The aim of this study was to investigate whether the changes of serum pepsinogen I/II ratio can be predicted by gastroscopy. Materials and Methods: Sixty healthy subjects who underwent screening for serum pepsinogen I/II levels, serum Helicobacter pylori (H. pylori) antibody, and gastroscopy for two sequential years were included. Endoscopic findings were classified into four different categories according to the degree of chronic atrophic gastritis; none, mild, moderate, and severe. Changes of the serum pepsinogen I/II ratio, body mass index, H. pylori antibody, and endoscopic findings were analyzed after a year. Results: The serum pepsinogen I/II ratio showed a tendency to decrease after a year in subjects with H. pylori infection (P=0.013) and those with moderate to severe atrophic gastritis (P=0.004), whereas it increased in subjects without H. pylori infection and those with none to mild atrophic gastritis. On multivariate analysis, the degree of atrophic gastritis was the only factor that was related to the changing trends of the serum pepsinogen I/II ratio (odds ratio=5.385, P=0.023). Conclusions: The degree of atrophic gastritis on endoscopic findings can predict the changes of the serum pepsinogen I/II ratio after a year. Regardless of the current status of H. pylori infection, the serum pepsinogen I/II ratio decreases after a year in subjects with moderate to severe atrophic gastritis. (Korean J Helicobacter Up Gastrointest Res 2012;12:96-102)

Post-polypectomy surveillance has become a major indication for colonoscopy as a result of increased use of screening colonoscopy in Korea. However, because the medical resource is limited, and the first screening colonoscopy produces the greatest effect on reducing the incidence and mortality of colorectal cancer, there is a need to increase the efficiency of postpolypectomy surveillance. In the present report, a careful analytic approach was used to address all available evidences to delineate the predictors for advanced neoplasia at surveillance colonoscopy. Based on the results of review of the evidences, we elucidated the high risk findings of the index colonoscopy as follows: 1) 3 or more adenomas, 2) any adenoma larger than 10 mm, 3) any tubulovillous or villous adenoma, 4) any adenoma with high-grade dysplasia, and 5) any serrated polyps larger than 10 mm. In patients without any high-risk findings at the index colonoscopy, surveillance colonoscopy should be performed five years after index colonoscopy. In patients with one or more high risk findings, surveillance colonoscopy should be performed three years after polypectomy. However, the surveillance interval can be shortened considering the quality of the index colonoscopy, the completeness of polyp removal, the patient's general condition, and family and medical history. This practical guideline cannot totally take the place of clinical judgments made by practitioners and should be revised and supplemented in the future as new evidence becomes available.