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.

Risk of Metachronous Colorectal Advanced Neoplasia and Cancer in Patients With 3-4 Nonadvanced Adenomas at Index Colonoscopy: A Systematic Review and Meta-Analysis.

INTRODUCTION: This systematic review and meta-analysis evaluated the available evidence on the risk of metachronous advanced neoplasia (AN) and colorectal cancer (CRC) in patients with 3-4 nonadvanced adenomas (NAAs). METHODS: We searched MEDLINE, EMBASE, and Cochrane Library databases up to January 2021 for studies evaluating metachronous AN and CRC risk by comparing 3 groups (1-2 vs 3-4 vs ≥5 NAAs) at index colonoscopy. The estimates for risk of metachronous AN and CRC were evaluated using random-effects models. RESULTS: Fifteen studies (n = 36,375) were included. The risk of metachronous AN was significantly higher in the 3-4 NAAs group than in the 1-2 NAAs group (relative risk [RR] 1.264, 95% confidence interval [CI] 1.053-1.518, P = 0.012; I2 = 0%); there was no difference between the ≥ 5 NAAs and 3-4 NAAs groups (RR 1.962, 95% CI 0.972-3.958, P = 0.060; I2 = 68%). The risks of metachronous CRC between the 1-2 NAAs and 3-4 NAAs groups (RR 2.663, 95% CI 0.391-18.128, P = 0.317; I2 = 0%) or the 3-4 NAAs and ≥ 5 NAAs groups (RR 1.148, 95% CI 0.142-9.290, P = 0.897; I2 = 0%) were not significantly different. DISCUSSION: Although the risk of metachronous AN was greater in the 3-4 NAAs group than in the 1-2 NAAs group, the risk of metachronous AN and CRC between the 3-4 NAAs and ≥ 5 NAAs groups was not different. This suggests that further studies on metachronous AN and CRC risk in the 3-4 NAAs group are warranted to confirm a firm ≥5-year interval surveillance 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.

Optimal procedure-related hospitalization using clinical pathway protocols following gastric endoscopic submucosal dissection.

BACKGROUND: The clinical pathway (CP) protocols simplified a systematic process from hospitalization to discharge, and were conducted to achieve standardization of the treatment process as well as improve outcomes. Thus, we investigated the optimal procedure-related hospitalization period following gastric endoscopic submucosal dissection (ESD) by comparing the rate of delayed bleeding (DB) and perforation according to CP protocols. METHODS: We retrospectively enrolled 630 patients who underwent ESD for gastric dysplasia or early gastric cancer (EGC); Group A (368 patients) followed Protocol A for a hospital stay of a single night; Group B (262 patients) followed Protocol B for a hospital stay of two nights. RESULTS: The patient characteristics were comparable between the two groups, except for pathologic diagnosis (42.1% in Group A vs. 32.1% in Group B for EGC). DB occurred in 21 patients, and there was no significant difference in the overall DB rates between Group A (12/368 = 3.3%) and Group B (9/262 = 3.4%) (P = 0.904). The DB rates were 2.5% (8/315) and 7.5% (4/53) in Group A, and 2.7% (6/223) and 7.7% (3/39) in Group B, without and with the use of antiplatelets, respectively, and 33.3% (1/3) in Group A and 50.0% (1/2) in Group B with the use of dual antiplatelets. DB developed at various intervals post-discharge from 2 to 17 days, and was successfully controlled by endoscopic hemostasis in most cases. There were no deaths or surgeries required as a result of uncontrolled DB and no postoperative delayed perforation occurred. CONCLUSIONS: The CP protocols with a one-night hospitalization following gastric ESD decreased the hospital stay and did not influence postoperative complications compared to those with two-night hospitalizations.

Ischemic colitis induced by indigo naturalis in a patient with ulcerative colitis: a case report.

BACKGROUND: Indigo naturalis is a Chinese herbal medicine that has currently been used to treat various inflammatory diseases, including ulcerative colitis. Recently, there are several reports concerning severe adverse events associated with indigo naturalis. CASE PRESENTATION: We described a case of a 44-year-old female with ulcerative colitis who presented with lower abdominal pain and hematochezia. She stopped taking her medicine for ulcerative colitis and started oral indigo naturalis 3 months before admission. Computed tomography showed segmental edematous wall thickening of the descending and sigmoid colon. Colonoscopy findings revealed erythema, edema, and submucosal hemorrhage, the surface of which presented a dark blue pigmentation. The histologic finding was consistent with ischemic colitis. We therefore considered an ischemic colitis induced by indigo naturalis, and the patient improved after supportive care and withdrawal of indigo naturalis. CONCLUSION: Indigo naturalis has currently been used in the patients with ulcerative colitis as an alternative therapy. However, physicians should be aware of possible severe adverse events such as ischemic colitis.

Nationwide validation study of diagnostic algorithms for inflammatory bowel disease in Korean National Health Insurance Service database.

BACKGROUND AND AIM: We conducted a nationwide validation study of diagnostic algorithms to identify cases of inflammatory bowel disease (IBD) within the Korea National Health Insurance System (NHIS) database. METHOD: Using the NHIS dataset, we developed 44 algorithms combining the International Classification of Diseases (ICD)-10 codes, codes for Rare and Intractable Diseases (RID) registration and claims data for health care encounters, and pharmaceutical prescriptions for IBD-specific drugs. For each algorithm, we compared the case identification results from electronic medical records data with the gold standard (chart-based diagnosis). A multiple sampling test verified the validation results from the entire study population. RESULTS: A random nationwide sample of 1697 patients (848 potential cases and 849 negative control cases) from 17 hospitals were included for validation. A combination of the ICD-10 code, ≥ 1 claims for health care encounters, and ≥ 1 prescription claims (reference algorithm) achieved excellent performance (sensitivity, 93.1% [95% confidence interval 91-94.7]; specificity, 98.1% [96.9-98.8]; positive predictive value, 97.5% [96.1-98.5]; negative predictive value, 94.5% [92.8-95.8]) with the lowest error rate (4.2% [3.3-5.3]). The multiple sampling test confirmed that the reference algorithm achieves the best performance regarding IBD diagnosis. Algorithms including the RID registration codes exhibited poorer performance compared with that of the reference algorithm, particularly for the diagnosis of patients affiliated with secondary hospitals. The performance of the reference algorithm showed no statistical difference depending on the hospital volume or IBD type, with P-value < 0.05. CONCLUSIONS: We strongly recommend the reference algorithm as a uniform standard operational definition for future studies using the NHIS database.

Predictive Factors for Differentiating Between Crohn's Disease and Intestinal Tuberculosis in Koreans.

OBJECTIVES: A differential diagnosis between intestinal tuberculosis (ITB) and Crohn's disease (CD) is challenging. The aim of this study was to investigate the clinical, endoscopic, and histological features and to create a predictive score model for differentiating CD and ITB. METHODS: In total, 261 patients, 99 with ITB and 162 with CD, were recruited from seven tertiary centers from 2005 to 2013 and reviewed retrospectively. For the creation of a validated model, parameters were selected by univariate logistic regression and receiver operating characteristic curve analyses. Then, the prediction model was established on the basis of ß-coefficients of the multivariate logistic regression. For the validation of the model, the same regression equation was tested on the other group. RESULTS: Age, diarrhea, ring-shaped ulcer, longitudinal ulcer, sigmoid involvement, suspicious radiological pulmonary tuberculosis, and gender were selected as the factors for a seven-marker model. In the seven-marker model of the validation data set, the sensitivity, specificity, positive predictive value, and negative predictive value with a cutoff level of 0.35 were 98.0, 92.4, 88.9, and 98.6, respectively. CONCLUSIONS: The seven-marker model seems to be highly reliable for differentiating between ITB and CD and could be conveniently used by clinicians to obtain results.

Eradication Rates of Helicobacter pylori in Korea Over the Past 10 years and Correlation of the Amount of Antibiotics Use: Nationwide Survey.

BACKGROUND: The efficacy of proton-pump inhibitor-amoxicillin-clarithromycin therapy for H. pylori eradication has decreased over time. OBJECTIVE: We assessed the trend of H. pylori eradication rates over the last 10 years and the relationship between the eradication rates and the amount of macrolide antibiotic use in a country with a high prevalence of H. pylori infection. METHODS: This vast nationwide multicenter study was conducted with 34,139 adults treated for H. pylori infection from January 2001 to December 2010. The defined daily dose per km(2) (DSD) of macrolide antibiotics was calculated (n = 141,019) using the Health Insurance Review & Assessment data base from 2008 to 2010 in the two cities which had the lowest (Jeju city) or highest (Chuncheon city) eradication rate. RESULTS: The eradication rates of proton-pump inhibitor-amoxicillin-clarithromycin therapy ranged 84.9-87.5% from 2001 to 2007, and those of 2008 to 2010 ranged 80.0-81.4% with a decreasing trend (p < 0.0001). The decreasing trend of eradication rates for the overall first-line therapy was observed only in three of the seven geographic areas in Korea (p < 0.0001). The DSD of macrolide antibiotics was significantly higher in Jeju than Cheunchon city (0.85 vs 0.52, p < 0.0001). CONCLUSIONS: H. pylori eradication rates with clarithromycin-containing triple therapy in Korea showed a decreasing trend over the past 10 years, although the trend varied among geographic areas. This difference may be associated with the amount of macrolide antibiotic use.

Predictors of Urgent Findings on Abdominopelvic CT in Patients with Crohn's Disease Presenting to the Emergency Department.

BACKGROUND: Patients with Crohn's disease (CD) are frequently exposed to diagnostic radiation, mainly as a result of abdominopelvic computed tomography (APCT) examinations. However, there are limited data on the impact of APCT on clinical management in this population. AIM: To investigate clinical predictors of urgent findings on APCT in patients with CD who presented to the emergency department (ED). METHODS: A retrospective study was performed among patients with CD presenting to 11 EDs with a gastrointestinal complaint. The primary outcome, OPAN (obstruction, perforation, abscess, or non-CD-related urgent findings), included new or worsening CD-related urgent findings or non-CD-related urgent findings that required urgent or emergency treatment. Variables with P < 0.1 in univariate analyses were included in a multivariable logistic regression model. RESULTS: Of the 266 APCTs performed, 103 (38.7 %) had OPAN and 113 (42.5 %) required changes in treatment plan. Stricturing or penetrating disease (odds ratio [OR] 2.72, 95 % confidence interval [CI] 1.21-6.13), heart rate >100 beats/min (OR 2.33, 95 % CI 1.10-4.93), leukocyte count >10,000/mm(3) (OR 4.38, 95 % CI 2.10-9.13), and CRP >2.5 mg/dL (OR 3.11, 95 % CI 1.23-7.86) were identified as the independent predictors of OPAN, whereas biologic agent use (OR 0.37; 95 % CI 0.15-0.90) was identified as the negative predictor in patients with CD. CONCLUSIONS: Only 39 % of the APCTs performed in the ED among patients with CD showed urgent findings. Stricturing or penetrating disease, tachycardia, leukocytosis, and high CRP level were predictors of urgent CT findings, while biologic agent use was a negative predictor. To reduce unnecessary radiation exposure, the selection process for CD patients referred for APCT must be improved.

Endoscopic and clinical analysis of primary T-cell lymphoma of the gastrointestinal tract according to pathological subtype.

BACKGROUND AND AIM: Little is known about the clinicopathological characteristics of primary gastrointestinal T-cell lymphomas (PGITL). This study evaluated the clinical and endoscopic features of the pathological subtypes of PGITL. METHODS: Forty-two lesions in 36 patients with PGITL were assessed, including 15 enteropathy-associated T-cell lymphomas (EATL), 13 peripheral T-cell lymphomas (PTCL), 10 NK/T-cell lymphomas (NK/TL), and four anaplastic large cell lymphomas (ALCL). RESULTS: PTCL occurred more frequently in the stomach and duodenum and NK/TL more frequently in the small and large intestines (P = 0.009). The endoscopic features of the four subtypes were similar (P = 0.124). Fifteen of 41 lesions (36.6%) were Epstein-Barr virus (EBV) positive, with NK/TL more likely to be EBV positive than the other types (P < 0.001). First endoscopy and first computed tomography (CT) scan indicated that 65.4% and 51.4% of the lesions, respectively, were malignant, and that 43.2% and 42.3%, respectively, were GI lymphomas. The two modalities together correctly diagnosed about half of the lesions before biopsy. Intestinal perforation was associated with small bowel location (P < 0.001) and infiltrative type (P = 0.009), and was more common in NK/TL than in the other subtypes (P = 0.015). Multivariate analysis showed that higher international prognosis index (P = 0.008) and the presence of complications (P = 0.006) were associated with poor prognosis. Survival was poorer in patients with small bowel lesions than with lesions at other locations (P = 0.048). CONCLUSIONS: The four main pathological types of PGITL differed in clinical characteristics. As PGITL was often not diagnosed by initial endoscopic or radiological examination, a high index of suspicion is necessary to ensure its early diagnosis.

Clinical features and predictors of clinical outcomes in Korean patients with Crohn's disease: a Korean association for the study of intestinal diseases multicenter study.

BACKGROUND AND AIM: Although differences in genetic susceptibility and the clinical features of Crohn's disease (CD) have been reported between Asian and Caucasian patients, the disease course and predictors of CD in Asians remains poorly defined. The study therefore aimed to investigate factors predictive of the clinical outcomes of patients with CD in a Korean population. METHODS: This retrospective multicenter cohort study included 728 Korean CD patients from 13 university hospitals. The first CD-related surgery or need for immunosuppressive or biological agents were regarded as the clinical outcomes of interest. RESULTS: A total of 126 (17.3%) CD patients underwent CD-related surgery, while 473 (65.0%) and 196 (26.9%) were prescribed thiopurine drugs and infliximab, respectively. Multivariate Cox regression analysis identified current (hazard ratio [HR] = 1.86; P = 0.018) and former smoking habits (HR = 1.78; P = 0.049), stricturing (HR = 2.24; P < 0.001), and penetrating disease behavior at diagnosis (HR = 3.07; P < 0.001) as independent predictors associated with the first CD-related surgery. With respect to immunosuppressive and biological agents, younger age (< 40 years) (HR = 2.17; P < 0.001 and HR = 2.10; P = 0.006, respectively), ileal involvement (HR = 1.36; P = 0.035 and HR = 2.17; P = 0.006, respectively), and perianal disease (HR = 1.42; P = 0.001 and HR = 1.38; P = 0.038, respectively) at diagnosis were significant predictors for the need of these medications. CONCLUSIONS: In Korean patients with CD, stricturing, penetrating disease behavior, and smoking habits at the time of diagnosis are independent predictors for CD-related surgery. It was also identified that younger age (< 40 years), ileal involvement, and perianal disease at diagnosis are predictive of a need for immunosuppressive or biological agents.

Clinical outcomes of colonic mucosal cancers with histologically positive or uncertain resection margin after endoscopic resection.

BACKGROUND/AIMS: Although incomplete endoscopic resection of colonic neoplasms can lead to the development of interval invasive cancer, few studies have assessed clinical outcomes after histologically incomplete resection of colonic mucosal cancer. We aimed to evaluate the clinical outcomes of patients with histologically positive or uncertain resection margins after endoscopically complete resection of colonic mucosal cancer. METHODOLOGY: We analyzed the clinical course of 38 patients (median 62 years, male:female = 27:11) who underwent endoscopically complete resection of colonic mucosal cancer, but who showed histologically positive or uncertain resection margins. RESULTS: The median size of the 38 colonic mucosal cancers was 14 mm (range, 5-50 mm). Of these, 20 were resected by a piecemeal resection, and had uncertain histological resection margins. The remaining 18 patients underwent en-bloc resection; of these, 16 had uncertain resection margins and 2 had positive margins. Patients underwent a median of 2.3 follow-up endoscopies (range, 1-7) during a median follow-up time of 18.3 months (range, 3-75 months). No local or distant recurrence was detected. CONCLUSIONS: Cautious followup without immediate additional treatment can be considered for patients who undergo endoscopically complete resection of colonic mucosal cancers, even when histological examination shows uncertain or positive resection margins.

Podoplanin, α-smooth muscle actin or S100A4 expressing cancer-associated fibroblasts are associated with different prognosis in colorectal cancers.

The interactions between the tumor microenvironment and tumor cells determine the behavior of the primary tumors. Whether cancer-associated fibroblasts (CAF) have a tumor progressive or a protective role likely depends on the type of tumor cells and the CAF subpopulation. In the present study, we analyzed the prognostic significance of CAF subpopulations in colorectal cancer (CRC). CAF phenotypes were analyzed in 302 CRC patients by using antibodies against podoplanin (PDPN), α-smooth muscle actin (α-SMA), and S100A4. The relationship between the CAF phenotypes and 11 clinicopathological parameters were evaluated and their prognostic significance was analyzed from the disease-free and overall survival times. We observed that at the tumor invasive front, PDPN CAFs were present in 40% of the cases, and S100A4 or α-SMA CAFs were detected in all the cases. PDPN/S100A4 and α-SMA/S100A4 dual-stained CAFs were observed in 10% and 40% of the cases, respectively. The PDPN(+) CAFs were associated with 6 favorable clinicopathological parameters and prolonged disease-free survival time. The PDPN(-)/α-SMA(high) CAFs were associated with 6 aggressive clinicopathological parameters and tended to exhibit shorter disease-free survival time. On the other hand, the PDPN(-)/S100A4(high) CAFs were associated with 2 tumor progression parameters, but not with disease prognosis. The PDPN(+) CAF phenotype is distinct from the α-SMA or S100A4 CAFs in that it is associated with less aggressive tumors and a favorable prognosis, whereas the PDPN(-)/α-SMA(high) or PDPN(-)/S100A4(high) CAFs are associated with tumor progression in CRC. These findings suggest that CAFs can be a useful prognostic biomarker or potential targets of anti-cancer therapy in CRC.

Korean Guidelines for Postpolypectomy Colonoscopic Surveillance: 2022 revised edition.

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: adenoma ≥10 mm in size; 3 to 5 (or more) adenomas; tubulovillous or villous adenoma; adenoma containing high-grade dysplasia; traditional serrated adenoma; sessile serrated lesion containing any grade of dysplasia; serrated polyp of at least 10 mm in size; and 3 to 5 (or more) sessile serrated lesions. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

Korean guidelines for postpolypectomy colonoscopic surveillance: 2022 revised edition.

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for the management of advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: (1) adenoma ≥10 mm in size; (2) 3 to 5 (or more) adenomas; (3) tubulovillous or villous adenoma; (4) adenoma containing high-grade dysplasia; (5) traditional serrated adenoma; (6) sessile serrated lesion (SSL) containing any grade of dysplasia; (7) serrated polyp of at least 10 mm in size; and (8) 3 to 5 (or more) SSLs. More studies are needed to fully comprehend the patients most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

[Korean Guidelines for Postpolypectomy Colonoscopic Surveillance: 2022 Revised Edition].

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: 1) adenoma ≥10 mm in size; 2) 3-5 (or more) adenomas; 3) tubulovillous or villous adenoma; 4) adenoma containing high-grade dysplasia; 5) traditional serrated adenoma; 6) sessile serrated lesion (SSL) containing any grade of dysplasia; 7) serrated polyp of at least 10 mm in size; and 8) 3-5 (or more) SSLs. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

Colonoscopic findings and histologic diagnostic yield of colorectal endometriosis.

BACKGROUND: No study has systematically investigated the colonoscopic findings and histologic diagnostic yield in the diagnosis of colorectal endometriosis. OBJECTIVES: We classified the colonoscopic features of colorectal endometriosis and determined the diagnostic yield of endoscopic biopsy in relation to endoscopic subtypes of colorectal endometriosis. METHODS: A total of 17 patients with colorectal endometriosis were assessed. The data from the colonoscopic and histologic assessments made between November 1994 and October 2009 were retrospectively analyzed in single tertiary referral teaching hospital. RESULTS: Colonoscopy showed eccentric wall thickening in 14 patients (82%) and polypoid lesions in 3 patients (18%). Surface nodularities were noted in 11 of the 14 patients (79%) with eccentric wall thickening, and in 1 of the 3 patients (33%) with polypoid lesions. The overall histologic diagnostic yield was 47% (8 of the 17 patients). The rate of histologic confirmation was higher in patients with surface nodularities (8 of the 12 patients, 67%) versus those without (0 of the 5 patients, 0%) surface nodularities (P=0.02). CONCLUSIONS: Eccentric wall thickening is the most common colonoscopic finding of colorectal endometriosis, and the histologic diagnostic yield of endoscopic biopsy is high when lesions are accompanied by surface nodularities.

Application of near-infrared fluorescence imaging using a polymeric nanoparticle-based probe for the diagnosis and therapeutic monitoring of colon cancer.

BACKGROUND: Early and accurate detection of adenomatous colonic polyps is a major concern in the prevention of colon cancer. Near-infrared fluorescence (NIRF) imaging with optical probes targeting specific peptides enables the noninvasive visualization and characterization of lesions. Matrix metalloproteinases (MMPs) are known to play an important role in tumorigenesis and tumor progression. AIM: To investigate the effectiveness of NIRF imaging, with a novel MMP-activatable probe based on a polymeric nanoparticle platform, in the colon cancer models. METHODS: We used an azoxymethane (AOM)-induced mouse colon cancer model resembling human sporadic colon cancer and an MMP-positive xenograft tumor model. MMP expression was evaluated by Western blotting, real-time PCR, and immunohistochemical staining. NIRF imaging was performed with a novel MMP-activatable probe, an MMP-inactivatable probe, and saline. In addition, we observed the change of NIRF signal intensity after intratumoral administration of an MMP-inhibitor. RESULTS: Multiple tumors with various sizes developed in AOM-treated mouse colons, progressing from adenomas to adenocarcinomas, with MMP expression progressively increasing in the normal-adenoma-adenocarcinoma sequence. In mice injected with the MMP-activatable probe, the NIRF signal also increased in this sequence and was highly correlated with MMP expression (p < 0.001). Tumor-background-ratios (TBR) of adenocarcinoma to adjacent normal mucosa by a novel probe were significantly higher than that of adenoma (p < 0.001). In both the AOM and xenograft models, NIRF signals of tumors decreased after treatment with an MMP-inhibitor. CONCLUSIONS: NIRF imaging using a polymeric nanoparticle-based probe may be useful for detecting early stage disease and for assessing treatment response.

Education can improve inter-observer agreement in double balloon endoscopy assessment.

BACKGROUND/AIMS: Double balloon endoscopy (DBE) diagnoses are difficult because of the frequent occurrence of tiny lesions or longitudinally arranged erythema, which may result from true pathologies or contact trauma during DBE insertion. This study was performed to explore interobserver agreement for DBE assessment and to determine whether this can be improved by educating endoscopists. METHODOLOGY: Three experienced endoscopists independently evaluated DBE pictures of an initial training set, consisting of 124 lesions in 78 patients with suspected small bowel bleeding. Each endoscopist made DBE diagnoses independently and assessed whether each lesion was or was not a source of bleeding. Tiny lesions were assessed twice, assuming they had been detected during DBE insertion and/or DBE withdrawal. After two sessions of consensus review by the endoscopists, they evaluated a second, validation set consisting of an additional 43 lesions in 30 patients. RESULTS: Inter-observer agreement with respect to DBE assessment was moderate in the initial training set, but improved to good in the second validation set. The proportion of diagnoses changed to DBE contact lesions when they were assumed to be detected during DBE withdrawal decreased in the second validation set. CONCLUSIONS: Although inter-observer agreement for DBE assessment is not excellent, it can be improved by education of endoscopists.

Endoscopic submucosal dissection for treatment of rectal carcinoid tumors.

BACKGROUND: Conventional EMR has been the endoscopic treatment of choice for rectal carcinoid tumors. However, histologically complete resection often cannot be achieved because the carcinoid tumors are located mainly in the submucosal layer. Endoscopic submucosal dissection (ESD), a new method for large colorectal neoplasm resection, may overcome this problem. OBJECTIVE: To compare ESD with EMR for the endoscopic treatment of rectal carcinoid tumors. DESIGN: A prospective case series with comparison to retrospective controls. SETTING: Tertiary-care center. PATIENTS: From January 2007 to January 2009 we prospectively enrolled consecutive patients with rectal carcinoid tumors less than 16 mm in diameter and with no regional lymph node enlargement shown by CT or EUS. For comparison, we retrospectively randomly selected patients who had undergone EMR for treatment of rectal carcinoid tumors between March 2000 and December 2006. INTERVENTION: We performed ESD of rectal carcinoid tumors in prospectively enrolled patients. MAIN OUTCOME MEASUREMENTS: Rate of en bloc resection, rate of histologically complete resection, incidence of complications, and length of procedures. RESULTS: The ESD group contained 31 patients (18 male, 13 female; age range 34-65 years), and the EMR group contained 62 patients (42 male, 20 female; age range 22-77 years). Both groups had similar mean rectal carcinoid tumor diameters (ESD 6.8 +/- 2.4 mm, EMR 7.3 +/- 2.2 mm; P = .106). Resection time was longer in the ESD group than in the EMR group (11.4 +/- 3.7 minutes vs 4.2 +/- 3.2 minutes, P < .001). The en bloc resection rate was 100% (31 of 31) in the ESD group and 95.2% (59 of 62) in the EMR group (P = .213). The histologically complete resection rate was 90.3% (28 of 31) in the ESD group and 71.0% (44 of 62) in the EMR group (P = .035). Suspected perforation occurred in 1 ESD patient (3.2%) and in 1 EMR patient (1.6%), and both patients were successfully managed by conservative measures. Immediate bleeding occurred in 1 ESD patient (3.2%) and in 4 EMR patients (6.5%); all instances of bleeding were controlled endoscopically. LIMITATIONS: Retrospective control study and limited experience at a single center. CONCLUSION: Compared with EMR, ESD resulted in a higher histologically complete resection rate, had a similar complication rate, and took slightly longer to perform. Given the advantages of complete resection, these findings indicate that ESD may be considered for treatment of rectal carcinoid tumors.