Diagnostic Value of Ileal Lesions Found during Colonoscopy with Reference to Endoscopic Indications and Findings.

The diagnostic value of ileoscopy is not well established, and its routine practice is controversial. We aimed to investigate the diagnostic value of biopsy for macroscopically abnormal lesions in the terminal ileum and to identify the association between endoscopic indications and findings and the presence of significant disease. This retrospective study included 551 patients who underwent biopsy of abnormal lesions in the terminal ileum (TI) during colonoscopy between February 2000 and June 2019. Biopsy results were analyzed in relation to the endoscopic indications and gross findings. Significant disease was defined as a case in which a specific disease was suspected or confirmed by the biopsy results, requiring additional examination or treatment. Among the 551 biopsies from macroscopically abnormal lesions in the TI, 44 (8.0%) had significant diseases. The frequency of significant disease was high in patients with clinically suspected inflammatory bowel disease (IBD) (50.0%), anemia (31.6%), right lower quadrant (RLQ) pain (28.6%), and radiological abnormalities in the TI (27.5%). The frequency of Crohn's disease (CD) was high in patients with clinically suspected IBD. A concurrent abnormality in the ileocecal valve (ICV) (14.3%) and the presence of an ulcer (14.2%), mass, or polyp (25.4%) correlated with a high incidence of significant disease, particularly CD. In cases of suspected IBD, anemia, RLQ pain, and radiologic abnormalities in the TI, there is a high possibility of significant disease. Ulcers, masses, polyps, and concurrent abnormalities in the ICV were also associated with significant disease.

Clinical importance of weight gain and associated factors in patients with moderate to severe ulcerative colitis: results from the MOSAIK cohort in Korea.

BACKGROUND: Many patients with ulcerative colitis (UC) gain weight after treatment. However, the clinical significance of weight gain in these patients remains unclear. This study aimed to evaluate body weight changes after treatment in patients newly diagnosed with moderate-to-severe UC and their effects on patients' prognosis. METHODS: The change in weight between diagnosis and 1 year after treatment in 212 patients enrolled in the MOSAIK cohort (mean age, 40 years; males, 60%) was analyzed. Significant weight gain was defined as a weight increase of ≥ 5% from the baseline at 1 year. Factors associated with significant weight gain and the effect of significant weight gain on the risk of major adverse outcomes (clinical relapse, hospitalization, and new use of steroids or biologics) during a follow-up period of 20 months were evaluated. RESULTS: Mean weight gain at 1 year was 1.7 ± 4.2 kg. The proportion of overweight/obese patients increased by 9.0% from 37.9% to 46.9%. Thirty-two percent had significant weight gain; extensive colitis at diagnosis was the only factor associated with significant weight gain (odds ratio 6.5, 95% confidence interval 1.4-31.0, p = 0.006). In multivariable analysis, significant weight gain was not associated with the risk of major adverse outcomes. Weight loss symptoms at diagnosis were associated with an increased risk for new steroid use after 1 year. CONCLUSIONS: Approximately one-third of patients with moderate-to-severe UC had significant weight gain after 1 year of treatment. However, significant weight gain was not associated with the patient's prognosis.

On-demand Versus Continuous Maintenance Treatment With a Proton Pump Inhibitor for Mild Gastroesophageal Reflux Disease: A Prospective Randomized Multicenter Study.

Background/Aims: It remains unclear which maintenance treatment modality is most appropriate for mild gastroesophageal reflux disease (GERD). We aimed to compare on-demand treatment with continuous treatment using a proton pump inhibitor (PPI) in the maintenance treatment for patients with non-erosive GERD or mild erosive esophagitis. Methods: Patients whose GERD symptoms improved after 4 weeks of standard dose PPI treatment were prospectively enrolled at 25 hospitals. Subsequently, the enrolled patients were randomly assigned to either an on-demand or a continuous maintenance treatment group, and followed in an 8-week interval for up to 24 weeks. Results: A total of 304 patients were randomized to maintenance treatment (continuous, n = 151 vs on-demand, n = 153). The primary outcome, the overall proportion of unwillingness to continue the assigned maintenance treatment modality, failed to confirm the non-inferiority of on-demand treatment (45.9%) compared to continuous treatment (36.1%). Compared with the on-demand group, the GERD symptom and health-related quality of life scores significantly more improved and the overall satisfaction score was significantly higher in the continuous treatment group, particularly at week 8 and week 16 of maintenance treatment. Work impairment scores were not different in the 2 groups, but the prescription cost was less in the on-demand group. Serum gastrin levels significantly elevated in the continuous treatment group, but not in the on-demand group. Conclusions: Continuous treatment seems to be more appropriate for the initial maintenance treatment of non-erosive GERD or mild erosive esophagitis than on-demand treatment. Stepping down to on-demand treatment needs to be considered after a sufficient period of continuous treatment.

Real-world Prescription Patterns and Patient Satisfaction Regarding Maintenance Therapy of Gastroesophageal Reflux Disease: An Observational, Cross-sectional, Multicenter Study.

Background/Aims: Gastroesophageal reflux disease (GERD) is a common chronic gastrointestinal disorder that typically requires long-term maintenance therapy. However, little is known about patient preferences and satisfaction and real-world prescription patterns regarding maintenance therapy for GERD. Methods: This observational, cross-sectional, multicenter study involved patients from 18 referral hospitals in Korea. We surveyed patients who had been prescribed proton pump inhibitors (PPIs) for GERD for at least 90 days with a minimum follow-up duration of 1 year. The main outcome was overall patient satisfaction with different maintenance therapy modalities. Results: A total of 197 patients were enrolled. Overall patient satisfaction, patient preferences, and GERD health-related quality of life scores did not significantly differ among the maintenance therapy modality groups. However, the on-demand therapy group experienced a significantly longer disease duration than the continuous therapy group. The continuous therapy group demonstrated a lower level of awareness of potential adverse effects associated with PPIs than the on-demand therapy group but received higher doses of PPIs than the on-demand therapy group. The prescribed doses of PPIs also varied based on the phenotype of GERD, with higher doses prescribed for non-erosive reflux disease than erosive reflux disease. Conclusion: Although overall patient satisfaction did not significantly differ among the different PPI maintenance therapy modality groups, awareness of potential adverse effects was significantly different between the on-demand and continuous therapy groups.

Efficacy and Safety of Fexuprazan in Patients with Acute or Chronic Gastritis.

Background/Aims: Fexuprazan is a novel potassium-competitive acid blocker that could be of benefit to patients with gastric mucosal injury. The aim of this study was to assess the 2-week efficacy and safety of fexuprazan in patients with acute or chronic gastritis. Methods: In this study, 327 patients with acute or chronic gastritis who had one or more gastric erosions on endoscopy and subjective symptoms were randomized into three groups receiving fexuprazan 20 mg once a day (q.d.), fexuprazan 10 mg twice a day (b.i.d.), or placebo for 2 weeks. The posttreatment assessments were the primary endpoint (erosion improvement rate), secondary endpoints (cure rates of erosion and edema and improvement rates of redness, hemorrhage, and subjective symptoms), and drug-related adverse events. Results: Among the patients, 57.8% (59/102), 65.7% (67/102), and 40.6% (39/96) showed erosion improvement 2 weeks after receiving fexuprazan 20 mg q.d., fexuprazan 10 mg b.i.d., and placebo, respectively. Both fexuprazan 20 mg q.d. and 10 mg b.i.d. showed superior efficacy to the placebo (p=0.017 and p<0.001, respectively). Likewise, both fexuprazan 20 mg q.d. and 10 mg b.i.d. also showed higher erosion healing rates than the placebo (p=0.033 and p=0.010, respectively). No difference was noted in the edema healing rate and the improvement rates for redness, hemorrhage, and subjective symptoms between the fexuprazan and placebo groups. No significant difference was noted in the incidence of adverse drug reactions. Conclusions: Fexuprazan 20 mg q.d. and 10 mg b.i.d. for 2 weeks showed therapeutic efficacy superior to that of placebo in patients with acute or chronic gastritis (ClinicalTrials.gov identifier NCT04341454).

Evaluation of the efficacy of 1 L polyethylene glycol plus ascorbic acid and an oral sodium sulfate solution: A multi-center, prospective randomized controlled trial.

INTRODUCTION: Low-volume bowel preparation has been developed to increase patient compliance. We compared 1 L of polyethylene glycol/ascorbic acid (PEG/Asc) and oral sodium sulfate (OSS) with respect to bowel preparation efficacy, compliance, and safety. METHODS: A multicenter, prospective, randomized, single-blinded, non-inferiority trial was conducted in 3 hospitals. Patients were randomized to receive a bowel-cleansing agent. Bowel-cleansing efficacy was evaluated using the Boston Bowel Preparation Scale (BBPS). Satisfaction, feeling, taste of the bowel cleanser, and adverse events after taking the bowel cleanser were investigated through a questionnaire. Additionally, blood samples were analyzed before and after bowel cleansing. RESULTS: In total, 172 patients were analyzed (85 with 1 L PEG/Asc and 87 with OSS), and the mean BBPS scores were comparable between agents. The 1L PEG/Asc group tended to have a higher BBPS score in the right colon (2.22 vs 2.02; P = .08). The compliance of 1 L of PEG/Asc was comparable to that of OSS. Patients taking 1 L PEG/Asc reported greater thirst and dizziness (P = .04 and P = .047, respectively) than the OSS cohort. On the other hand, gastrointestinal symptoms such as vomiting and abdominal distension were more common in the OSS group, without statistical significance. In terms of laboratory adverse events, elevation of serum creatinine was found in both groups after taking the bowel cleansing agent (P < .001 for the 1L PEG/Asc group; P = .04 for the OSS group). However, most of the increased values were within the normal ranges. DISCUSSION: The 1L PEG/Asc treatment was comparable to OSS in terms of bowel preparation efficacy, compliance, and safety.

Eosinophil and Mast Cell Counts in the Stomach and Duodenum of Patients with Functional Dyspepsia without a Helicobacter pylori infection.

Background/Aims: Symptom-based subtyping of functional dyspepsia (FD) is used to segregate patients into groups with homogenous pathophysiological mechanisms. This study examined whether subtyping could reflect the duodenal and gastric microinflammation in FD patients. Methods: Twenty-one FD patients without Helicobacter pylori infection were recruited. An endoscopic biopsy was performed in the duodenum 2nd portion, stomach antrum, and body. The eosinophil and mast cell counts per high-power field (×40) were investigated by H&E and c-kit staining, respectively. The degree of inflammatory cell infiltration, atrophy, and intestinal metaplasia was also determined by H&E staining in the stomach. The baseline characteristics and eosinophil and mast cell infiltrations were compared among the three groups (epigastric pain syndrome, postprandial distress syndrome, and overlap). Results: According to the symptom assessment, seven subjects were classified into the epigastric pain syndrome group, 10 into the postprandial syndrome group, and four into the overlap group. The baseline variables were similar in the three groups. Eosinophil infiltration was more prominent in the duodenum than in the stomach. In contrast, mast cell infiltration was similar in the duodenum and stomach. The eosinophil counts in the duodenum were similar in the three groups. The eosinophil counts in the stomach and mast cell counts in the duodenum and stomach were also similar in the three groups. Conclusions: Duodenal eosinophil infiltration was prominent in FD patients, but the eosinophil counts were similar regardless of the symptom-based subtypes of FD. Hence, the current symptom-based subtyping of FD does not reflect duodenal eosinophil and mast cell infiltration.

Clinical Features and Long-term Prognosis of Crohn's Disease in Korea: Results from the Prospective CONNECT Study.

Background/Aims: The prospective Crohn's Disease Clinical Network and Cohort Study is a nationwide multicenter cohort study of patients with Crohn's disease (CD) in Korea, aiming to prospectively investigate the clinical features and long-term prognosis associated with CD. Methods: Patients diagnosed with CD between January 2009 and September 2019 were prospectively enrolled. They were divided into two cohorts according to the year of diagnosis: cohort 1 (diagnosed between 2009 and 2011) versus cohort 2 (between 2012 and 2019). Results: A total of 1,175 patients were included, and the median follow-up duration was 68 months (interquartile range, 39.0 to 91.0 months). The treatment-free durations for thiopurines (p<0.001) and anti-tumor necrosis factor agents (p=0.018) of cohort 2 were shorter than those of cohort 1. Among 887 patients with B1 behavior at diagnosis, 149 patients (16.8%) progressed to either B2 or B3 behavior during follow-up. Early use of thiopurine was associated with a reduced risk of behavioral progression (adjusted hazard ratio [aHR], 0.69; 95% confidence interval [CI], 0.50 to 0.90), and family history of inflammatory bowel disease was associated with an increased risk of behavioral progression (aHR, 2.29; 95% CI, 1.16 to 4.50). One hundred forty-one patients (12.0%) underwent intestinal resection, and the intestinal resection-free survival time was significantly longer in cohort 2 than in cohort 1 (p=0.003). The early use of thiopurines (aHR, 0.35; 95% CI, 0.23 to 0.51) was independently associated with a reduced risk of intestinal resection. Conclusions: The prognosis of CD in Korea appears to have improved over time, as evidenced by the decreasing intestinal resection rate. Early use of thiopurines was associated with an improved prognosis represented by a reduced risk of intestinal resection.

Colonic Chicken Skin Mucosa Surrounding Colon Polyps Is an Endoscopic Predictive Marker for Colonic Neoplastic Polyps.

Background/Aims: Narrow band imaging provides an accurate diagnosis of colonic polyps. However, these diagnostic modalities are not used as standard endoscopic tools in most institutions. This study aims to investigate whether the chicken skin mucosa (CSM) surrounding the colon polyp yields additional information about colorectal polyps, including histological differentiation of neoplastic and non-neoplastic polyps, under conventional white light colonoscopy. Methods: This study prospectively observed 173 patients who underwent endoscopic polypectomy and reviewed the clinical data and pathologic reports of 313 polyps from a university hospital. Two endoscopists each performed colonoscopy and polypectomy and assessed the CSM. The association between CSM surrounding colorectal polyps and histology was analyzed. Results: The majority (91.3%) of CSM-positive polyps were neoplastic (sensitivity, 37.90%; specificity, 86.15%; p<0.001). In logistic regression, the neoplastic polyps were associated with positive CSM (adjusted odds ratio [OR], 3.51; 95% confidence interval [CI], 1.45 to 9.25; p=0.007), protruded polyps (adjusted OR, 4.85; 95% CI, 1.65 to 17.23; p=0.008), and neoplastic histology-associated pit pattern (pit III, IV, and V) (adjusted OR, 10.14; 95% CI, 4.85 to 22.12; p=0.000). Furthermore, advanced adenomas were associated with positive CSM (adjusted OR, 5.64; 95% CI, 1.77 to 20.28; p=0.005), protruded polyps (adjusted OR, 3.30; 95% CI, 1.15 to 9.74; p= 0.026), and ≥10 cm polyp size (adjusted OR, 18.56; 95% CI, 3.89 to 147.01; p=0.001). Conclusions: Neoplastic and advanced polyps were associated with CSM-positive polyps. These findings suggest that CSM is a useful marker in differentiating neoplastic polyps and advanced polyps under conventional white colonoscopy.

Early course of newly diagnosed moderate-to-severe ulcerative colitis in Korea: Results from a hospital-based inception cohort study (MOSAIK).

BACKGROUND AND AIM: No inception cohort study has ever evaluated the early course of moderate-to-severe ulcerative colitis (UC) within 1 year of diagnosis in the non-Caucasian population. We aimed to investigate the early clinical course of moderate-to-severe UC patients in terms of remission, relapse, UC-related hospitalizations, colectomy, mortality, and overall use of medications. METHODS: In the MOSAIK inception cohort, which is an ongoing multicenter, prospective, hospital-based, observational cohort, 354 patients with moderate-to-severe UC were followed up for 1 year. Main outcomes of UC and predictive factors for medication use over the course of 1 year were evaluated. RESULT: Among 354 patients, 276 (78.0%) patients were followed up for 1 year. The rates of remission, relapse, UC-related hospitalizations, and proximal disease extension were 95.3%, 39.6%, 15.2%, and 12.3%, respectively. Systemic corticosteroids, thiopurines, and biologics were administered to 61.2%, 30.4%, and 10.5% of patients, respectively, throughout 1 year. One year after, 58.2% patients experienced remission or mild endoscopic activity. Overall disease courses did not show much difference according to moderate or severe disease activity at baseline. In addition, no colectomy and mortality were observed for 1 year. Predictive factors for medication use included disease severity, disease extent, endoscopic severity, and presence of periappendiceal inflammation at baseline for corticosteroid, disease extent and initial corticosteroid use for thiopurine, and only initial corticosteroid use for biologics. CONCLUSION: Korean patients with moderate-to-severe UC may have more favorable early outcomes than Western patients. However, outcomes of them need to be further looked into for a longer time.

The Effect of Metformin in Treatment of Adenomas in Patients with Familial Adenomatous Polyposis.

Familial adenomatous polyposis (FAP) is a hereditary disease characterized by the development of numerous colorectal adenomas in young adults. Metformin, an oral diabetic drug, has been shown to have antineoplastic effects and a favorable safety profile. We performed a randomized, double-blind, controlled trial to evaluate the efficacy of metformin on the regression of colorectal and duodenal adenoma in patients with FAP. Thirty-four FAP patients were randomly assigned in a 1:2:2 ratio to receive placebo, 500 mg metformin, or 1,500 mg metformin per day orally for 7 months. The number and size of polyps and the global polyp burden were evaluated before and after the intervention. This study was terminated early based on the results of the interim analysis. No significant differences were determined in the percentage change of colorectal and duodenal polyp number over the course of treatment among the three treatment arms (P = 0.627 and P = 1.000, respectively). We found no significant differences in the percentage change of colorectal or duodenal polyp size among the three groups (P = 0.214 and P = 0.803, respectively). The overall polyp burdens of the colorectum and duodenum were not significantly changed by metformin treatment at either dosage. Colon polyps removed from the metformin-treated patients showed significantly lower mTOR signal (p-S6) expression than those from patients in the placebo arm. In conclusion, 7 months of treatment with 500 mg or 1,500 mg metformin did not reduce the mean number or size of polyps in the colorectum or duodenum in FAP patients (ClinicalTrials.gov ID: NCT01725490). PREVENTION RELEVANCE: A 7-month metformin treatment (500 mg or 1,500 mg) did not reduce the number or size of polyps in the colorectum or duodenum of FAP patients as compared to placebo. These results do not support the use of metformin to promote regression of intestinal adenomas in FAP patients.

Sleep disorders in patients with functional dyspepsia: A multicenter study from the Korean Society of Neurogastroenterology and Motility.

BACKGROUND AND AIM: The few studies concerning the association between sleep disorders and functional dyspepsia (FD) have yielded inconsistent results. We compared the prevalence of sleep disorders in patients with FD and healthy controls, and evaluated whether FD was independently associated with sleep disorders, and the risk factors for sleep disorders in patients with FD. METHODS: This prospective, multicenter, cross-sectional study was conducted from August 2014 to December 2017 at 12 hospitals in South Korea. The inclusion criterion was the presence of FD (for ≥18 years) according to the Rome III criteria. Healthy controls were recruited from among patients who visited the Health Examination Center for check-ups. RESULTS: In total, 526 subjects were prospectively enrolled in this study (201 with FD and 325 healthy controls). The prevalence of sleep disorders was significantly higher among the patients with FD than among the healthy controls (41.8% vs 18.8%, P = 0.000). In a multivariate analysis, FD (odds ratio [OR] = 1.851; 95% confidence interval [CI] 1.194-2.870; P = 0.006), female sex (OR = 1.672; 95% CI 1.063-2.628; P = 0.026), and anxiety (OR = 3.325; 95% CI 2.140-5.166; P = 0.000) were independent risk factors for sleep disorders in the overall cohorts. In patients with FD only, low body mass index, heartburn, and anxiety were independent risk factors for sleep disorders in a further multivariate analysis. CONCLUSION: Sleep disorders were common in patients with FD. FD was significantly associated with sleep disorders in our patient population, irrespective of the presence of heartburn or psychiatric disorders.

Impact of Endoscopists' Personality Traits on Adenoma and Polyp Detection Rates in Colonoscopy: A KASID Multicenter Study.

BACKGROUND: The personality traits of endoscopists have been suggested to affect the adenoma detection rate (ADR). We thus evaluated the relationship between endoscopists' personality traits and the ADR during colonoscopy using the Minnesota Multiphasic Personality Inventory-2 (MMPI-2). METHODS: In total, 1230 patients (asymptomatic and aged 50-80 years) who underwent screening or surveillance (≥ 5 years) colonoscopy were recruited from 13 university hospitals by 20 endoscopists between September 2015 and December 2017. We retrospectively measured the ADR, polyp detection rate (PDR), and number of adenomas per colonoscopy (APC). All 20 endoscopists completed all 567 true/false MMPI-2 items. RESULTS: The overall mean colonoscopy withdrawal time, PDR, ADR, and APC were 7.3 ± 2.8 min, 55%, 45.3%, and 0.97 ± 1.58, respectively. No significant difference was observed in the MMPI-2 clinical scales (e.g., hypochondriasis and psychasthenia), content scales (e.g., obsessiveness and type A character), or supplementary scales (e.g., dominance and social responsibility) between the high ADR group (ADR ≥45%, n = 10) and the low ADR group (ADR < 45%, n = 10). In multivariate logistic regression analysis, the ADR was associated significantly with patient age and sex. The ADR was related significantly to endoscopists' colonoscopy experience and the per-minute increase in the colonoscopy withdrawal time (OR 1.21, 95% CI 1.06-1.38, p = 0.005). In a logistic regression analysis adjusted for patient factors, the ADR was associated significantly with ego strength (OR 1.04, 95% CI 1.00-1.09, p = 0.044), as measured by the MMPI-2. CONCLUSIONS: With the exception of ego strength, the endoscopists' personality traits were not associated with adenoma or polyp detection.

Clinical comparison of low-volume agents (oral sulfate solution and sodium picosulfate with magnesium citrate) for bowel preparation: the EASE study.

BACKGROUND/AIMS: This study compared the efficacy, compliance, and safety of bowel preparation between sodium picosulfate with magnesium citrate (SPMC) and oral sulfate solution (OSS). METHODS: A prospective randomized multicenter study was performed. Split preparation methods were performed in both groups; the SPMC group, 2 sachets on the day before, and 1 sachet on the day of the procedure, the OSS group, half of the OSS with 1 L of water on both the day before and the day of the procedure. The adenoma detection rate (ADR), adequacy of bowel preparation using the Boston Bowel Preparation Scale (BBPS) score, patient satisfaction on a visual analog scale (VAS), and safety were compared between the 2 groups. RESULTS: This study analyzed 229 patients (121 in the SPMC group and 108 in the OSS group). ADR showed no differences between 2 groups (51.7% vs. 41.7%, P> 0.05). The mean total BBPS score (7.95 vs. 8.11, P> 0.05) and adequate bowel preparation rate (94.9% vs. 96.3%, P> 0.05) were similar between the 2 groups. The mean VAS score for taste (7.62 vs. 6.87, P=0.006) was significantly higher in the SPMC group than in the OSS group. There were no significant differences in any other safety variables between the 2 groups except nausea symptom (36.1% vs. 20.3%, P=0.008). CONCLUSIONS: Bowel preparation for colonoscopy using low volume OSS and SPMC yielded similar ADRs and levels of efficacy. SPMC had higher levels of satisfaction for taste and feeling than did OSS.

Randomised phase 3 trial: tegoprazan, a novel potassium-competitive acid blocker, vs. esomeprazole in patients with erosive oesophagitis.

BACKGROUND: Tegoprazan is a novel potassium-competitive acid blocker that has a fast onset of action and can control gastric pH for a prolonged period, which could offer clinical benefit in acid-related disorders. AIM: To confirm the non-inferiority of tegoprazan to esomeprazole in patients with erosive oesophagitis (EE). METHODS: In this multicentre, randomised, double-blind, parallel-group comparison study, 302 Korean patients with endoscopically confirmed EE (Los Angeles Classification Grades A-D) were randomly allocated to either tegoprazan (50 or 100 mg) or esomeprazole (40 mg) treatment groups for 4 or 8 weeks. The primary endpoint was the cumulative proportion of patients with healed EE confirmed by endoscopy up to 8 weeks from treatment initiation. Symptoms, safety and tolerability were also assessed. RESULTS: The cumulative healing rates at week 8 were 98.9% (91/92), 98.9% (90/91) and 98.9% (87/88) for tegoprazan 50 mg, tegoprazan 100 mg and esomeprazole 40 mg, respectively. Both doses of tegoprazan were non-inferior to esomeprazole 40 mg. The incidence of adverse events was comparable among the groups, and tegoprazan was well-tolerated. CONCLUSION: Once daily administration of tegoprazan 50 or 100 mg showed non-inferior efficacy in healing EE and tolerability to that of esomeprazole 40 mg.

Frequency and Characteristics of Interval Colorectal Cancer in Actual Clinical Practice: A KASID Multicenter Study.

Background/Aims: The aims of the present study were to determine the frequency of interval colorectal cancers (CRCs) after surveillance colonoscopy and to compare the clinicopathologic features and survival outcomes with those of non-interval CRCs. Methods: From January 2003 to December 2013, 66,016 follow-up colonoscopies for 38,412 patients performed within recommended time were reviewed retrospectively based on data from 11 tertiary hospitals in South Korea. To compare clinicopathologic features and survival rates for interval CRC, 106 patients with non-interval CRC matched in age and gender were included. Results: Among the 66,016 colonoscopies performed within the surveillance period, 63 cases (63/66,016) of interval CRC were detected, and 53 were finally included in the analysis. The mean age was 69.9±8.8 years, and the male to female ratio was 1.94:1. Although the occurrence rate of cancer in the right side colon was higher than that of non-interval CRC, interval CRCs were predominantly left sided. Other clinicopathologic features and overall survival were not significantly different between the two groups. Missed lesion was suspected to be the most common cause (29 cases, 54.7%). Conclusions: The frequency of interval CRC among patients who had undergone a surveillance colonoscopy was 0.095%. While sharing some similar clinical features and survival outcomes, interval CRCs in Korea developed more often in males and on the left side in contrast to results from Western studies.

Risks of colorectal advanced neoplasia in young adults versus those of screening colonoscopy in patients aged 50 to 54 years.

BACKGROUND AND AIM: The role of screening or diagnostic colonoscopy to detect advanced neoplasia in young cohorts of age < 50 is unclear. This study compared the risk of colorectal neoplasia in a young age cohort against that in 50-54s screening cohort. METHODS: A multi-center retrospective study was conducted at 14 university hospitals to compare the detection rates of neoplasia and advanced neoplasia in screening or diagnostic colonoscopy in the young cohort of < 50s against those in screening colonoscopy in the 50-54s cohort. RESULTS: Among 10 477 eligible subjects, 9765 subjects were enrolled after excluding 712 subjects. Advanced neoplasia detection rates in the young screening cohort was significantly lower than that in the 50-54s screening cohort (5.9% vs 9.3%, P < 0.001). Compared with 50-54s screening cohort, the risk of advanced neoplasia was significantly reduced by 23%, 53%, and 54% in the 45-49s, 40-44s, and 20-39s screening cohorts, respectively. The detection rates of advanced neoplasia in the young diagnostic cohort was 5.0%, which was much lower than 11.8% in 50-54s screening cohort (P < 0.001). Compared with the 50-54s screening cohort, the risk of advanced neoplasia was significantly reduced by 50%, 66%, and 71% in the 45-49s, 40-44s, and 20-39s diagnostic cohorts, respectively. CONCLUSIONS: Colonoscopy to detect advanced neoplasia in young adults aged < 50 years should be reconsidered as their risk of advanced neoplasia on screening or diagnostic colonoscopy was much lower than those of 50-54s screening cohort; however, colonoscopy screening may be justified for high-risk 45-49s cohorts.

Influence of age at diagnosis on the clinical characteristics of Crohn's disease in Korea: Results from the CONNECT study.

BACKGROUND AND AIM: The present study evaluated the clinical characteristics of Korean patients with Crohn's disease (CD) according to their age at diagnosis in a nationwide multicenter cohort study. METHODS: A total of 1224 patients diagnosed with CD between 1982 and 2008 in 32 hospitals were included, and age at diagnosis was categorized as ≤ 16 (G1), 17-40 (G2), 41-59 (G3) and ≥ 60 (G4) years old. The baseline characteristics, medication, and intestinal resection were compared according to the age at diagnosis. RESULTS: The number of patients in each age group was 155 (G1; 12.7%), 919 (G2; 75.1%), 120 (G3; 9.8%), and 30 (G4; 2.5%). The frequencies of ileocolonic disease in the late adult onset and elderly onset groups were lower than those in the other groups (P < 0.001). The cumulative probabilities of thiopurine and anti-tumor necrosis factor use in late adult onset and elderly onset groups were significantly reduced compared with those of the other groups (P < 0.01). However, the risk of the first intestinal resection was not different among the age groups. The ileal location (hazard ratio [HR]: 1.59; 95% confidence interval [CI]: 1.11-2.27), complicated behavior (HR: 3.35; 95% CI: 2.63-4.27), and early thiopurine use (HR: 0.27; 95% CI: 0.17-0.43) were associated with the first intestinal resection, whereas the age at diagnosis was not a risk factor. CONCLUSIONS: Elderly onset CD may be related to favorable outcomes in Korea. Thus, the heterogeneity of this disease should be considered when developing a tailored strategy for the treatment of CD.

Clinical and Biological Features of Interval Colorectal Cancer.

Interval colorectal cancer (I-CRC) is defined as a CRC diagnosed within 60 months after a negative colonoscopy, taking into account that 5 years is the "mean sojourn time." It is important to prevent the development of interval cancer. The development of interval colon cancer is associated with female sex, old age, family history of CRC, comorbidities, diverticulosis, and the skill of the endoscopist. During carcinogenesis, sessile serrated adenomas/polyps (SSA/Ps) share many genomic and colonic site characteristics with I-CRCs. The clinical and biological features of I-CRC should be elucidated to prevent the development of interval colon cancer.