Reading of small bowel capsule endoscopy after frame reduction using an artificial intelligence algorithm.

OBJECTIVES: Poorly visualized images that appear during small bowel capsule endoscopy (SBCE) can confuse the interpretation of small bowel lesions and increase the physician's workload. Using a validated artificial intelligence (AI) algorithm that can evaluate the mucosal visualization, we aimed to assess whether SBCE reading after the removal of poorly visualized images could affect the diagnosis of SBCE. METHODS: A study was conducted to analyze 90 SBCE cases in which a small bowel examination was completed. Two experienced endoscopists alternately performed two types of readings. They used the AI algorithm to remove poorly visualized images for the frame reduction reading (AI user group) and conducted whole frame reading without AI (AI non-user group) for the same patient. A poorly visualized image was defined as an image with < 50% mucosal visualization. The study outcomes were diagnostic concordance and reading time between the two groups. The SBCE diagnosis was classified as Crohn's disease, bleeding, polyp, angiodysplasia, and nonspecific finding. RESULTS: The final SBCE diagnoses between the two groups showed statistically significant diagnostic concordance (k = 0.954, p < 0.001). The mean number of lesion images was 3008.5 ± 9964.9 in the AI non-user group and 1401.7 ± 4811.3 in the AI user group. There were no cases in which lesions were completely removed. Compared with the AI non-user group (120.9 min), the reading time was reduced by 35.6% in the AI user group (77.9 min). CONCLUSIONS: SBCE reading after reducing poorly visualized frames using the AI algorithm did not have a negative effect on the final diagnosis. SBCE reading method integrated with frame reduction and mucosal visualization evaluation will help improve AI-assisted SBCE interpretation.

Side-by-side placement of fully covered metal stents versus conventional 7F plastic stents in malignant hilar biliary obstruction: Prospective randomized controlled trial.

OBJECTIVES: We aimed to evaluate the efficacy and safety of metal stents compared with plastic stents when bilateral side-by-side stents were deployed for malignant hilar biliary obstruction (MHBO). METHODS: Fifty patients with unresectable advanced MHBO were randomly assigned to the metal stent (MS, n = 25) or plastic stent group (PS, n = 25). Fully covered self-expandable metal stents with 6 mm diameter and plastic stents with either 7F straight or double pigtail were used for MS and PS groups, respectively. Time to recurrent biliary obstruction (TRBO) was evaluated as the primary outcome. RESULTS: Both groups had 100% technical success rates; 88% and 76% of clinical success rates were obtained in MS and PS, respectively. Although stent migrations were more frequent in MS than PS (48% vs. 16%, P = 0.02), the mean TRBO was significantly longer in MS (190 days; 95% confidence interval [CI] 121-260 days vs. 96 days; 95% CI 50-141 days, P = 0.02). The placement of plastic stents (hazard ratio 2.42; 95% CI 1.24-4.73; P = 0.01) was the only significant risk factor associated with TRBO in multivariable analysis. The rates of adverse events were similar between the two groups (difference 0%; 95% CI -25% to 25%; P > 0.99). CONCLUSIONS: During bilateral side-by-side deployment in MHBO, the use of metal stents appears to be preferable to plastic stents in terms of TRBO, despite a higher frequency of stent migration.

In-stent radiofrequency ablation with uncovered metal stent placement for tumor ingrowth/overgrowth causing self-expandable metal stent occlusion in distal malignant biliary obstruction: multicenter propensity score-matched study.

BACKGROUND AND AIMS: In patients with unresectable malignant biliary obstruction (MBO), endoscopic drainage with a self-expandable metal stent (SEMS) is a well-established treatment, but stent patency is limited. This study aimed to evaluate the efficacy of in-stent radiofrequency ablation (IS-RFA) followed by uncovered SEMS placement for the management of occluded SEMSs. METHODS: From 2016 to 2020, 48 patients with recurrent biliary obstruction due to tumor ingrowth or overgrowth after SEMS placement for pancreatobiliary cancer in 3 tertiary hospitals were analyzed. For distal MBO, patients in the RFA group were treated with IS-RFA and uncovered SEMS placement, and those in the control group were treated with uncovered SEMS placement alone. Patients in both groups were matched on the basis of propensity scores in a 1:1 ratio. RESULTS: The median time to recurrent biliary obstruction (TRBO) was 117 days in the RFA group and 82.5 days in the control group (P = .029). No significant differences in median overall survival were detected between the 2 groups (170 days vs 72 days; P = .902). No significant adverse events were reported after the second SEMS placement in either group, but 2 cases of mild cholangitis were reported in the control group. Ablation was interrupted in 5 patients (35.7%) of the RFA group owing to in-stent contact, but sufficient ablative energy was delivered in the majority of the patients (92.9%) after IS-RFA was repeated in the same session. CONCLUSIONS: IS-RFA followed by an uncovered SEMS is safe and feasible and may improve TRBO as a stent revision for occluded SEMSs in pancreatobiliary cancer.

Long-term outcomes of endoscopic papillectomy for ampullary adenoma with high-grade dysplasia or adenocarcinoma: a propensity score-matched analysis.

BACKGROUND: Evidence of endoscopic papillectomy (EP) for ampullar adenoma with high-grade dysplasia (HGD) or adenocarcinoma is insufficient. Here we investigated the long-term outcomes of the advanced ampullary tumors treated by EP with careful surveillance comparing to subsequent surgery after EP. METHODS: Patients treated with EP for ampullary adenoma with HGD or adenocarcinoma from the multi-center retrospective Korean cohort of ampulla of Vater tumor were categorized into EP alone versus EP with subsequent surgery groups. The overall survival (OS) and recurrence-free survival (RFS) were analyzed for unmatched and matched cohorts using propensity score with nearest neighbor method. RESULTS: During a median 43.3 months of follow-up, 5-year OS was not significantly different between the EP alone and EP surgery groups (91.9% vs. 82.3%, P = 0.443 for unmatched cohort; 89.2% vs. 82.3%, P = 0.861 for matched cohort, respectively). Furthermore, 5-year RFS was not significantly different between the two groups (82.1% vs. 86.7%, P = 0.520 for unmatched cohort; 66.1% vs. 86.7%, P = 0.052 for matched cohort, respectively). However, the patients with positive both (lateral and deep) margins showed significantly poorer survival outcomes than those with negative margins within the EP alone group (P = 0.007). CONCLUSION: EP alone with careful surveillance showed comparable survival outcomes to those of EP with subsequent surgery for ampullar HGD or adenocarcinoma. Resection margin status could be a parameter to determine whether to perform subsequent radical surgery after EP.

Incidence of colonoscopy-related perforation and risk factors for poor outcomes: 3-year results from a prospective, multicenter registry (with videos).

BACKGROUND AND AIMS: Perforation is a life-threatening adverse event of colonoscopy that often requires hospitalization and surgery. We aimed to prospectively assess the incidence of colonoscopy-related perforation in a multicenter registry and to analyze the clinical factors associated with poor clinical outcomes. METHODS: This prospective observational study was conducted at six tertiary referral hospitals between 2017 and 2020, and included patients with colonic perforation after colonoscopy. Poor clinical outcomes were defined as mortality, surgery, and prolonged hospitalization (> 13 days). Logistic regression was used to identify factors associated with poor clinical outcomes. RESULTS: Among 84,673 patients undergoing colonoscopy, 56 had colon perforation (0.66/1000, 95% confidence interval [CI] 0.51-0.86). Perforation occurred in 12 of 63,602 diagnostic colonoscopies (0.19/1000, 95% CI 0.11-0.33) and 44 of 21,071 therapeutic colonoscopies (2.09/1000, 95% CI 1.55-2.81). Of these, 15 (26.8%) patients underwent surgery, and 25 (44.6%) patients had a prolonged hospital stay. One patient (1.8%) died after perforation from a diagnostic colonoscopy. In the multivariate analysis, diagnostic colonoscopy (adjusted odds ratio [aOR] 196.43, p = 0.025) and abdominal rebound tenderness (aOR 17.82, p = 0.012) were independent risk factors for surgical treatment. The location of the sigmoid colon (aOR 18.57, p = 0.048), delayed recognition (aOR 187.71, p = 0.008), and abdominal tenderness (aOR 63.20, p = 0.017) were independent risk factors for prolonged hospitalization. CONCLUSIONS: This prospective study demonstrated that the incidence of colonoscopy-related perforation was 0.66/1000. The incidence rate was higher in therapeutic colonoscopy, whereas the risk for undergoing surgery was higher in patients undergoing diagnostic colonoscopy. Colonoscopy indication (diagnostic vs. therapeutic), physical signs, the location of the sigmoid perforation, and delayed recognition were independent risk factors for poor clinical outcomes in colonoscopy-related perforation.

Natural Course of Early Detected Acute Peripancreatic Fluid Collection in Moderately Severe or Severe Acute Pancreatitis.

Background and Objectives: Acute peripancreatic fluid collection (APFC) is an acute local complication of acute pancreatitis (AP) according to the revised Atlanta classification. Sometimes APFC resolves completely, sometimes it changes into a pseudocyst or walled-off necrosis (WON), so called late complications. The aim of this study is to investigate the natural course of APFC detected on early computed tomography (CT) in moderately severe (MSAP) or severe AP (SAP). Materials and Methods: From October 2014 to September 2015, patients with MSAP or SAP were enrolled if there was APFC within 48 h of onset on imaging studies at six medical centers. The status of fluid collection was followed 4-8 weeks after onset. Initial laboratory findings, CT findings and clinical scoring systems were analyzed. Results: A total of 68 patients were enrolled and APFC was completely resolved in 32 (66.7%) patients in the MSAP group and 9 (34.6%) in the SAP group. Patients with a high bedside index for severity in acute pancreatitis (BISAP) score (≥3 points) were common in the SAP group. C-reactive protein (CRP) after 48 h from admission and BUN level were also high in the SAP group. In multivariate analysis, BISAP score (≥3 points), elevation of CRP after 48 h (≥150 mg/L) and nasojejunal feeding after 48 h were risk factors for the development of late complications. Conclusions: Spontaneous resolution of APFC was more common in MSAP group and APFC can be changed to pseudocyst or WON in patients with elevated BISAP score, CRP level after 48 h, and non-improved abdominal pain.

Impact of the COVID-19 pandemic on medical students of clinical clerkship in South Korea: A qualitative study exploring medical students' experiences.

Background and Objective: In 2020, during the coronavirus disease (COVID-19) pandemic, medical students were placed in a learning environment that exposed them to unsafe clinical settings. In this study, using a phenomenological approach, we analyze the experiences of fourth-year students in the Daegu area of South Korea, a region that experienced a high concentration of COVID-19 infections. Methods: The essays of 80 students from four medical schools who agreed to participate in the study were utilized in the final data analysis. The data were analyzed using the proposed phenomenological analysis. Results: Forty-seven condensed meaning units, twelve subthemes, and three essential themes were identified. The main theme includes the following: 1) confusion and stress due to sudden changes in the learning situation 2) learned the medical professionalism of physicians 3) reflection and internal change regarding what it means to be a physician. Conclusions: The COVID-19 pandemic had a significant impact on students who participated in clinical clerkships. This study can provide baseline data for planning educational strategies and establishing a support system for students in response to the changes that they may experience in the event of the reoccurrence of a novel infectious disease in the future.

Comparison of different types of covered self-expandable metal stents for malignant colorectal obstruction.

BACKGROUND: Stent migration is one of the main drawbacks of covered self-expandable metal stent (SEMSs), occurring in up to 40% of malignant colorectal obstruction management cases. Various types of covered SEMSs have been developed to reduce this risk. We aimed to compare the effectiveness and complication rates of the flare-type covered SEMS (Flare) with those of the double-layered covered SEMS (ComVi). METHODS: We performed a prospective, randomized study in four tertiary referral centers between July 2016 and April 2018. Patients with malignant colorectal obstruction were eligible for the study. The primary outcome was migration rate as observed within the first month. Rates of technical success, clinical success, and complications within the first month were also assessed. RESULTS: A total of 60 patients were included (mean age, 70.5 ± 12.5 years; male, 31 [51.7%]). Flare and ComVi stents were applied in 30 patients each. The Flare and ComVi groups showed comparable technical success rates (90% [27/30] vs. 96.7% [29/30], p = 0.605) and clinical success rates (85.2% [23/27] vs. 75.9% [22/29], p = 0.589). Migration occurred in three (11.1%) and four (13.8%) cases in the Flare and ComVi groups, respectively, without significant difference (p = 0.99), and the risk of other complications, including perforation and re-obstruction, did not differ between the two groups. CONCLUSIONS: Our study indicates that both flare-shape and double-layered covered SEMSs are equally effective options for the management of malignant colorectal obstruction with low migration rates when compared with previously reported migration risk of covered SEMS.

Mesothelin Expression Is a Predictive Factor for Peritoneal Recurrence in Curatively Resected Stage III Gastric Cancer.

BACKGROUND: Mesothelin is overexpressed in many solid tumors, and recent studies have shown that mesothelin expression is associated with poor outcomes in several malignant tumors and may play a role in cancer progression. Clinical trials of mesothelin-targeted immunotherapies are currently under way, but the correlation between mesothelin expression and gastric cancer prognosis is still unclear. SUBJECTS, MATERIALS, AND METHODS: Mesothelin expression in tumor cells was evaluated immunohistochemically in 958 patients with advanced gastric cancer and interpreted according to the intensity and extent of staining. Samples were scored from 0 to 2, with high expression defined as a score of 2. Clinicopathological factors, overall survival (OS), recurrence-free survival (RFS), and sites of initial recurrence, including peritoneal recurrence, were evaluated. Staging was performed according to the American Joint Committee on Cancer 7th edition. RESULTS: High mesothelin expression was observed in 49.7% of patients and significantly associated with high pathologic T (p = .021) and peritoneal recurrence (p = .018). Multivariate survival analysis showed that high mesothelin expression was independently associated with poor RFS (p = .001), OS (p = .001), and peritoneal recurrence (p = .002) in addition to stage, lymphovascular invasion, and Lauren classification. In a subgroup analysis of peritoneal recurrence, high mesothelin expression was also an independent prognostic factor in stage III (p = .013) and diffuse/mixed type gastric cancer (p = .010). CONCLUSION: High mesothelin expression is correlated with poor outcomes. In addition, mesothelin expression, Lauren classification, and stage are meaningful predictive factors for peritoneal recurrence. Moreover, mesothelin was a significant predictor of a high risk of peritoneal recurrence in patients with stage III gastric cancer. IMPLICATIONS FOR PRACTICE: This study demonstrates that high mesothelin expression correlates with poor outcomes and is a significant predictor of peritoneal recurrence in patients with stage III gastric cancer. This study provides instrumental evidence for designing anti-mesothelin antibody-drug conjugate clinical trials in patients with diffuse-type gastric cancer to reduce their high risk of peritoneal carcinomatosis.

Therapeutic outcomes of endoscopic papillectomy for ampullary neoplasms: retrospective analysis of a multicenter study.

BACKGROUND: Endoscopic papillectomy (EP) is reported to be a relatively safe and reliable procedure for complete resection of ampullary neoplasms. The aim of this study was to evaluate the therapeutic outcomes and complications of EP for ampullary neoplasms. METHODS: A retrospective multicenter study was conducted with 5 participating centers from January 2007 to July 2014. A total of 104 patients who underwent EP for ampullary neoplasms were reviewed retrospectively. EP was performed by snare resection with or without submucosal lifting of the lesion. RESULTS: The mean age of patients was 60.5 ± 12.1 years, and the male-to-female ratio was 2.0:1. En bloc resection was possible in 94 patients (90.3%). A biliary and a pancreatic stent were placed after EP in 42 patients and in 60 patients, respectively. A pathologically incomplete resection was noted in 11 cases (10.6%), and 5 of these patients were treated with additional endoscopic procedure. Histology of resected specimens was as follows: low grade adenoma (43.2%), high grade adenoma (14.4%), adenocarcinoma (16.3%), hyperplastic polyp (7.7%), and others (18.4%). Of the 75 cases with low grade adenoma on biopsy specimen, 21.3% turned out to have high grade adenoma (12%) or adenocarcinoma (9.3%). Procedure-related complications occurred in 33 patients (31.7%); bleeding (18 cases, 17.3%), pancreatitis (16 cases, 15.4%), and perforation (8 cases, 7.7%). Pre-EP ERCP, saline lifting, sphincterotomy, biliary stenting, pancreatic stenting, specimen size, and cauterization were not related to post EP complications. Surgery was performed in 6 cases with pathological incomplete resection and 2 cases with complications after EP, and there were 2 cases of mortality due to complications. During follow-up endoscopy after initial success of EP, remnant tumors were found in 7 patients, one of whom underwent surgery and the others were treated endoscopically. Consequently, the overall endoscopic success rate of EP was 89.4%. CONCLUSIONS: Endoscopic papillectomy appears to be an effective treatment for ampullary neoplasms, and can be considered as an alternative to surgery. However, relatively high risk of procedure related complications is a problem that must be considered.

Transpapillary drainage has no added benefit on treatment outcomes in patients undergoing EUS-guided transmural drainage of pancreatic pseudocysts: a large multicenter study.

BACKGROUND AND AIMS: The need for transpapillary drainage (TPD) in patients undergoing transmural drainage (TMD) of pancreatic fluid collections (PFCs) remains unclear. The aims of this study were to compare treatment outcomes between patients with pancreatic pseudocysts undergoing TMD versus combined (TMD and TPD) drainage (CD) and to identify predictors of symptomatic and radiologic resolution. METHODS: This is a retrospective review of 375 consecutive patients with PFCs who underwent EUS-guided TMD from 2008 to 2014 at 15 academic centers in the United States. Main outcome measures included TMD and CD technical success, treatment outcomes (symptomatic and radiologic resolution) at follow-up, and predictors of treatment outcomes on logistic regression. RESULTS: A total of 375 patients underwent EUS-guided TMD of PFCs, of which 174 were pseudocysts. TMD alone was performed in 95 (55%) and CD in 79 (45%) pseudocysts. Technical success was as follows: TMD, 92 (97%) versus CD, 35 (44%) (P = .0001). There was no difference in adverse events between the TMD (15%) and CD (14%) cohorts (P = .23). Median long-term (LT) follow-up after transmural stent removal was 324 days (interquartile range, 72-493 days) for TMD and 201 days (interquartile range, 150-493 days) (P = .37). There was no difference in LT symptomatic resolution (TMD, 69% vs CD, 62%; P = .61) or LT radiologic resolution (TMD, 71% vs CD, 67%; P = .79). TPD attempt was negatively associated with LT radiologic resolution of pseudocyst (odds ratio, 0.11; 95% confidence interval, 0.02-0.8; P = .03). CONCLUSIONS: TPD has no benefit on treatment outcomes in patients undergoing EUS-guided TMD of pancreatic pseudocysts and negatively affects LT resolution of PFCs.

The Impact of Gallbladder Status on Biliary Complications After the Endoscopic Removal of Choledocholithiasis.

BACKGROUND: Endoscopic sphincterotomy (EST) with stone extraction is the standard management for choledocholithiasis. However, the necessity for subsequent management of gallstone to prevent the biliary complications remained controversial and few data were evaluated for the impact of status of gallbladder on recurrent biliary complications. We retrospectively investigated the relationship between the status of gallbladder and the occurrence of biliary complications after endoscopic removal of choledocholithiasis. METHODS: Between January 1998 and December 2008, we enrolled 453 patients with intact gallbladder who underwent EST for choledocholithiasis and allocated into two groups: calculous gallbladder (n = 256) and acalculous gallbladder (n = 197). By reviewing patients' medical records, we compared the occurrence of biliary complications according to the presence or absence of gallstone in GB in situ. RESULTS: In total, biliary complications occurred in 83 patients (18.3 %) during the follow-up period. Calculous GB group had higher rate of overall complications (22.7 vs. 12.7 %; p = 0.007) and GB-associated complications (11.3 vs. 2.5 %; p = 0.001) than acalculous GB group. On the multivariate analysis, only the presence of gallstone was shown to be significant risk factor for overall biliary complication (OR 2.029; 95 % CI 1.209-3.405; p = 0.007) and GB-associated complications (OR 5.077; 95 % CI 1.917-13.446; p = 0.001). Mean event-free period was shorter in calculous GB group than acalculous GB group for overall complications (1774 vs. 2159 days; p = 0.012) and GB-associated complication (2153 vs. 2591 days; p = 0.001). CONCLUSIONS: Prophylactic cholecystectomy may not be necessary to prevent biliary complication in patients with acalculous gallbladder after endoscopic removal of pigment stones from bile duct.

Should prophylactic cholecystectomy be performed in patients with concomitant gallstones after endoscopic sphincterotomy for bile duct stones?

BACKGROUND: Endoscopic sphincterotomy (EST) is the standard treatment for biliary duct stones. However, performing additional cholecystectomy after EST is controversial. In this study, we aimed to evaluate the effects of cholecystectomy after EST. METHODS: Between December 2008 and July 2011, we performed a prospective, randomized, single-center trial in 90 patients with proven gallstones who underwent EST and stone extraction. After the procedure, patients were randomly allocated to undergo cholecystectomy (n = 45) or to the group of GB left in situ (n = 45). The primary outcome was biliary complications at follow-up. RESULTS: Cholecystectomy was performed in 26 patients (60.5 %) in cholecystectomy group and in 13 patients (28.9 %) in intended conservative group. The median follow-up was 41 months. An intention-to-treat analysis showed that 8 patients (18.6 %) in the cholecystectomy group and 9 (20.0 %) in those who had their GB left in situ had recurrent biliary events (Kaplan-Meier curve, Breslow test, p = 0.555). In an as-treated analysis, 4 patients (10.3 %) who underwent cholecystectomy and 13 patients (26.5 %) who did not undergo cholecystectomy had additional biliary events during the follow-up period (Log-rank, p = 0.037). However, additional biliary events of cholangitis were similar in the two groups, except for a case of cholecystitis (Log-rank, p = 0.998). CONCLUSIONS: Cholecystectomy after EST for biliary duct stones fails to reduce additional recurrent cholangitis but reduces additional cholecystitis.

Risk factors of open converted cholecystectomy for cholelithiasis after endoscopic removal of choledocholithiasis.

BACKGROUND: Open converted cholecystectomy could occur in patients who planned for laparoscopic cholecystectomy after endoscopic removal of choledocholithiasis. AIM: To evaluate the risk factors associated with open converted cholecystectomy. PATIENTS AND METHODS: The data for all patients who underwent cholecystectomy after endoscopic removal of choledocholithiasis were retrospectively reviewed. Factors predictive for conversion to open cholecystectomy were analyzed. RESULTS: The rate of open converted cholecystectomy was 15.7 %. In multivariate analysis, cholecystitis (OR 1.908, 95 % CI 1.390-6.388, p = 0.005), mechanical lithotripsy (OR 6.129, 95 % CI 1.867-20.123, p < 0.005), and two or more choledocholithiases (OR 2.202, 95 % CI 1.097-4.420, p = 0.026) revealed significant risk factors for conversion to open cholecystectomy. Analyzing the risk factors for open converted cholecystectomy according to duration from endoscopic stone removal to cholecystectomy (within 2 weeks, between 2 and 6 weeks, and beyond 6 weeks), acute cholangitis (OR 3.374, 95 % CI 1.267-8.988, p = 0.015), cholecystitis (OR 3.127, 95 % CI 1.100-8.894, p = 0.033), and mechanical lithotripsy (OR 17.504, 95 % CI 3.548-86.355, p < 0.005) were related to open converted cholecystectomy in ≤2 weeks group. CONCLUSIONS: For patients who need cholecystectomy after endoscopic removal of choledocholithiasis, endoscopic retrograde cholangiography-related factors predictive for open converted cholecystectomy are helpful in planning the appropriate timing of surgery.

Endoscopic resection as the first-line treatment for early colorectal cancer: comparison with surgery.

INTRODUCTION: Endoscopic resection has emerged as an alternative therapeutic option for selected cases of early colorectal cancer. However, even now, few data are available on the comparative effectiveness of endoscopic versus surgical resection of early colorectal cancer. The aim of our study was to compare the clinical outcomes in patients with early colorectal cancer who underwent endoscopic resection and those who underwent surgical resection. METHODS: 292 early colorectal cancer lesions in 287 patients who were treated with either endoscopic resection or colorectal surgery (open or laparoscopic colorectal resection) between January 2005 and December 2010 were retrospectively analyzed. After excluding 54 deep submucosal lesions [and/or tumor budding (Grade 2 or 3)], a total of 168 lesions with mucosal/superficial submucosal invasion were treated by endoscopic resection, and 70 lesions with mucosal/superficial submucosal invasion were treated by colorectal surgery. RESULTS: In the endoscopic resection group, the en bloc resection rate and the complete resection rate were 91.1 and 91.1%, respectively. In the colorectal surgery group, both the en bloc resection rate and the curative resection rate were 100%. However, using Log rank test in Kaplan-Meier curve, no significant difference in recurrence rate (including metachronous cancer) during the median follow-up period of 37 months (range, 6-98 months) was observed between the two groups (p = 0.647). In addition, a similar morbidity rate was observed for endoscopic resection compared with surgery (5.4 vs. 5.7%, p = 0.760). A significantly shorter hospital stay was observed in the endoscopic resection group than colorectal surgery group [median 2 days (range, 2-29) vs. median 10 days (range, 7-37), p < 0.001). CONCLUSION: We suggest that endoscopic resection, being equally effective but less invasive than surgery, can be the first-line treatment for well selected early colorectal cancer.

Incidence, risk factors and clinical course of pancreatic fluid collections in acute pancreatitis.

BACKGROUND: Acute pancreatitis is an acute inflammatory process of the pancreas with variable involvement of other regional tissues or remote organ systems. Acute fluid collections and pseudocyst formation are the most frequent complications of acute pancreatitis. AIMS: The aims of this study were to evaluate the incidence, risk factors, and clinical course of pancreatic fluid collections and pseudocyst formation following acute pancreatitis. METHODS: A prospective multicenter study was conducted in five participating centers with 302 patients diagnosed with acute pancreatitis from January 2011 to July 2012. RESULTS: The incidence of pancreatic fluid collections and pseudocyst was 42.7 and 6.3 %, respectively. Patients with fluid collections were significantly younger, compared to those without fluid collections (51.5 ± 15.9 vs. 60.4 ± 16.5 years, P = 0.000). The proportion of alcoholic etiology (54.3 %) in patients with fluid collections was significantly higher compared to other etiologies (P = 0.000). C-reactive protein (CRP) (48 h) was significantly higher in patients with fluid collections, compared to patients without fluid collections (39.2 ± 77.4 vs. 15.1 ± 36.2 mg/dL, P = 0.016). LDH (48 h) was significantly higher in patients with pseudocyst formation, compared to patients with complete resolution (1,317.6 ± 706.4 vs. 478.7 ± 190.5 IU/L, P = 0.000). Pancreatic fluid collections showed spontaneous resolution in 69.8 % (90/129) and 84.2 % of the pseudocysts disappeared or decreased in size during follow up. CONCLUSIONS: Age, CRP (48 h), and alcohol etiology are risk factors for pancreatic fluid collections. LDH (48 h) appears to be a risk factor for pseudocyst formation. Most pseudocysts showed a decrease in size or spontaneous resolution with conservative management.

A tailored approach for endoscopic treatment of small rectal neuroendocrine tumor.

INTRODUCTION: Resection of rectal neuroendocrine tumors (NETs) less than 1 cm in diameter can be performed using various endoscopic techniques. Endoscopic mucosal resection (EMR) traditionally had suboptimal complete resection rate compared to endoscopic submucosal resection with band ligation (ESMR-L). However, the previous studies did not consider the characteristics of rectal NETs. The aim of our study is to compare the efficacy of ESMR-L and EMR using tailored approach according to the characteristics of rectal NETs. METHODS: 82 rectal NETs in 77 patients treated by ESMR-L (n = 48) or EMR (n = 34) between September 2007 and October 2012 were retrospectively analyzed. ESMR-L was used for flat-type tumors or tumors with non-lifting sign after submucosal injection. Conventional EMR was used for elevated-type tumors or tumors with well-lifting sign after submucosal injection. RESULTS: The pathological complete resection rate was higher in the ESMR-L group (45 lesions, 93.8%) compared with the EMR group (30 lesions, 88.2%); however, this difference was not significant (p = 0.441). Overall complication did not differ significantly between the ESMR-L group and the EMR group (p = 0.774). There was one case of a remnant lesion in the ESMR-L group, which was managed by EMR after circumferential pre-cutting (EMR-P), and no recurrence has been detected in either the ESMR-L or EMR group. CONCLUSIONS: ESMR-L and EMR procedures could have a similar excellent complete resection rate, if we select the endoscopic resection technique according to the characteristics of the small rectal NETs.

Inter-observer agreement in the endoscopic classification of colorectal laterally spreading tumors: a multicenter study between experts and trainees.

BACKGROUND AND AIM: The risk of cancer varies with the subtype of colorectal "laterally spreading tumors" (LSTs). However, visual interpretations vary among endoscopists. The aim of this study was to evaluate inter-observer agreement and accuracy in the endoscopic classification of LST subtypes among experts and trainees. METHODS: In total, 40 LST images were collected and reviewed independently by 14 gastroenterology experts and 10 trainees. All investigators recorded their findings as one of the following four categories: homogeneous, nodular mixed, flat-elevated, and pseudo-depressed. Agreement was assessed in terms of the kappa (κ) statistic and AC1 estimate. Accuracy is reported as percentage agreement with the gold standard, based on the gross morphology of the resected specimens. RESULTS: Of the possible 91 pair-wise κ estimates among experts, 41 (45.1%) were >0.75, indicating excellent agreement, while only 2 (4.44%) of the 45 pair-wise κ estimates among trainees were >0.75. Agreements for individual LST subtypes in the trainee group were significantly lower than those in the expert group. The κ and AC1 estimates showed similar values in individual subtypes of LSTs. The overall accuracy of LST was also significantly higher for the experts than the trainees (85.9 vs. 72.5%, P < 0.001). Notably, the flat-elevated subtype showed the lowest agreement and accuracy and was frequently misclassified as the pseudo-depressed subtype by both groups. CONCLUSIONS: Inter-observer agreement and accuracy for LST subtype classification differ significantly between experts and trainees. Implementation of an adequate training system for beginners is necessary to better identify colorectal LSTs.

Iatrogenic pancreatitis in patients with IPMN after ERCP: incidence and predictive signs.

BACKGROUND AND AIMS: The prevalence of intraductal papillary mucinous neoplasm (IPMN) has recently increased, and endoscopic retrograde cholangiopancreatography (ERCP) is a major diagnostic modality for IPMN. The aim of our study was to determine the prevalence rate of iatrogenic pancreatitis in the patients with IPMN and the predictive signs on pre-procedural images and endoscopic procedures. PATIENTS AND METHODS: At a single center, patients who underwent ERCP between September 2001 and December 2010 were included in this study. The presence of iatrogenic pancreatitis was evaluated and the difference of prevalence in the patients with/without IPMN was determined. Then, a review of cross-sectional images was performed. RESULTS: The prevalence rate of iatrogenic pancreatitis in the patients with IPMN was 20% and that in the patients with other pancreatic cystic lesions was 14%. Mural nodules on images and filling defects on ERCP were more highly detected in the patients without iatrogenic pancreatitis (p = 0.040 and p = 0.027, respectively). In the multivariate analysis, the presence of filling defects correlated with a decreased incidence of iatrogenic pancreatitis (odds ratio = 0.119 and p = 0.047). CONCLUSION: In this study, the prevalence rate of ERCP-induced pancreatitis in the patients with IPMN was 21%, and the presence of filling defects was associated with a decreased incidence of iatrogenic pancreatitis.

Two human cases of Diphyllobothrium nihonkaiense infection in Korea.

Diphyllobothrium latum and Diphyllobothrium nihonkaiense are the 2 reported main causes of human diphyllobothriasis in the Republic of Korea. However, the differentiation of these 2 species based on morphologic features alone is difficult. The authors used nucleotide sequencing of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene to diagnose Diphyllobothrium spp. Two patients visited the emergency room at Kyungpook National University Hospital on 3 April and 12 April 2013, respectively, with fragments of parasites found while defecating. The parasites were identified as Diphyllobothrium spp. based on morphologic characteristics, and subsequent cox1 gene sequencing showed 99.9% similarity (1,478/1,480 bp) with D. nihonkaiense. Our findings support the hypothesis that D. nihonkaiense is a dominant species in Korea.