A colonial serrated polyp classification model using white-light ordinary endoscopy images with an artificial intelligence model and TensorFlow chart.

In this study, we implemented a combination of data augmentation and artificial intelligence (AI) model-Convolutional Neural Network (CNN)-to help physicians classify colonic polyps into traditional adenoma (TA), sessile serrated adenoma (SSA), and hyperplastic polyp (HP). We collected ordinary endoscopy images under both white and NBI lights. Under white light, we collected 257 images of HP, 423 images of SSA, and 60 images of TA. Under NBI light, were collected 238 images of HP, 284 images of SSA, and 71 images of TA. We implemented the CNN-based artificial intelligence model, Inception V4, to build a classification model for the types of colon polyps. Our final AI classification model with data augmentation process is constructed only with white light images. Our classification prediction accuracy of colon polyp type is 94%, and the discriminability of the model (area under the curve) was 98%. Thus, we can conclude that our model can help physicians distinguish between TA, SSA, and HPs and correctly identify precancerous lesions such as TA and SSA.

The Extended Surgical Concepts for Hepatocellular Carcinoma in the Era of Immune Checkpoint Inhibitors.

Surgical resection remains one of the most effective curative therapies for HCC. However, the majority of patients have advanced unresectable diseases upon presentation. It is of paramount importance to raise the resectability of patients with HCC. The remarkable objective response rate reported by Phase III IMbrave150 trial has led to the concept of "Atezo/Bev followed by curative conversion (ABC conversion)" for initially unresectable HCC. With this revolutionary treatment strategy, the concept of surgical resection for HCC should be amended. The current opinion illustrated three extended surgical concepts, which could be integrated into clinical practice in the era of immune checkpoint inhibitors (ICI).

The Impact of Metabolic Factors and Lipid-Lowering Drugs on Common Bile Duct Stone Recurrence after Endoscopic Sphincterotomy with Following Cholecystectomy.

BACKGROUND: Recurrent common bile duct stone after endoscopic retrograde cholangiopancreatography is an undesirable problem, even when a following cholecystectomy is carried out. Important factors are the composition and properties of stones; the most significant etiology among these is the lipid level. While numerous studies have established the association between serum lipid levels and gallstones, no study has previously reported on recurrent common bile duct stones after endoscopic sphincterotomy with following cholecystectomy. MATERIALS AND METHODS: We retrospectively collected 2016 patients underwent endoscopic sphincterotomy from 1 January 2015 to 31 December 2017 in Linkou Chang Gung Memorial Hospital. Finally, 303 patients whose serum lipid levels had been checked following a cholecystectomy after ERCP were included for analysis. We evaluated if metabolic factors including body weight, BMI, HbA1C, serum lipid profile, and lipid-lowering drugs may impact the rate of common bile duct stone recurrence. Furthermore, we tried to find if there is any factor that may impact time to recurrence. RESULTS: A serum HDL level ≥ 40 (p = 0.000, OR = 0.207, 95% CI = 0.114-0.376) is a protective factor, and a total cholesterol level ≥ 200 (p = 0.004, OR = 4.558, 95% CI = 1.625-12.787) is a risk factor of recurrent common bile duct stones after endoscopic sphincterotomy with cholecystectomy. Lipid-lowering drugs, specifically statins, have been shown to reduce the risk of recurrence significantly (p = 0.003, OR = 0.297, 95% CI = 0.132-0.665). No factors were found to impact the time to recurrence in this study. CONCLUSIONS: The serum lipid level could influence the recurrence of common bile duct stones after endoscopic sphincterotomy followed by cholecystectomy, and it appears that statins can reduce the risk of recurrence.

Efficacy of Fully Covered Self-Expandable Metal Stents for Distal Biliary Obstruction Caused by Pancreatic Ductal Adenocarcinoma: Primary Metal Stent vs. Metal Stent following Plastic Stent.

Fully covered self-expandable metallic stents (FCSEMSs) are inserted in patients with unresectable pancreatic ductal adenocarcinoma (PDAC) to resolve malignant distal bile duct obstructions. Some patients receive FCSEMSs during primary endoscopic retrograde cholangiopancreatography (ERCP), and others receive FCSEMSs during a later session, after the placement of a plastic stent. We aimed to evaluate the efficacy of FCSEMSs for primary use or following plastic stent placement. A total of 159 patients with pancreatic adenocarcinoma (m:f, 102:57) who had achieved clinical success underwent ERCP with the placement of FCSEMSs for palliation of obstructive jaundice. One-hundred and three patients had received FCSEMSs in a first ERCP, and 56 had received FCSEMSs after prior plastic stenting. Twenty-two patients in the primary metal stent group and 18 in the prior plastic stent group had recurrent biliary obstruction (RBO). The RBO rates and self-expandable metal stent patency duration did not differ between the two groups. An FCSEMS longer than 6 cm was identified as a risk factor for RBO in patients with PDAC. Thus, choosing an appropriate FCSEMS length is an important factor in preventing FCSEMS dysfunction in patients with PDAC with malignant distal bile-duct obstruction.

Optimal Timing of Cholecystectomy for Patients with Concurrent Acute Cholecystitis and Acute Cholangitis after Successful Biliary Drainage by Interventional Endoscopic Retrograde Cholangiopancreatography.

Background: Concurrent acute cholecystitis and acute cholangitis is a unique clinical situation. We tried to investigate the optimal timing of cholecystectomy after adequate biliary drainage under this condition. Methods: From January 2012 to November 2017, we retrospectively screened all in-hospitalized patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) and then identified patients with concurrent acute cholecystitis and acute cholangitis from the cohort. The selected patients were stratified into two groups: one-stage intervention (OSI) group (intended laparoscopic cholecystectomy at the same hospitalization) vs. two-stage intervention (TSI) group (interval intended laparoscopic cholecystectomy). Interrogated outcomes included recurrent biliary events, length of hospitalization, and surgical outcomes. Results: There were 147 patients ultimately enrolled for analysis (OSI vs. TSI, 96 vs. 51). Regarding surgical outcomes, there was no significant difference between the OSI group and TSI group, including intraoperative blood transfusion (1.0% vs. 2.0%, p = 1.000), conversion to open procedure (3.1% vs. 7.8%, p = 0.236), postoperative complication (6.3% vs. 11.8%, p = 0.342), operation time (118.0 min vs. 125.8 min, p = 0.869), and postoperative days until discharge (3.37 days vs. 4.02 days, p = 0.643). In the RBE analysis, the OSI group presented a significantly lower incidence of overall RBE (5.2% vs. 41.2%, p < 0.001) than the TSI group. Conclusions: Patients with an initial diagnosis of concurrent acute cholecystitis and cholangitis undergoing cholecystectomy after ERCP drainage during the same hospitalization period may receive some benefit in terms of clinical outcomes.

Timing of endoscopic retrograde cholangiopancreatography in the treatment of acute cholangitis of different severity.

BACKGROUND: The optimal timing of endoscopic retrograde cholangiopancreatography (ERCP) in acute cholangitis (AC) is uncertain, especially in patients with AC of varying severity. AIM: To report whether the timing of ERCP is associated with outcomes in AC patients with different severities. METHODS: According to the 2018 Tokyo guidelines, 683 patients who met the definite diagnostic criteria for AC were retrospectively identified. The results were first compared between patients receiving ERCP ≤ 24 h and > 24 h and then between patients receiving ERCP ≤ 48 h and > 48 h. Subgroup analyses were performed in patients with grade I, II or III AC. The primary outcome was 30-d mortality. Secondary outcomes were intensive care unit (ICU) admission rate, length of hospital stay (LOHS) and 30-d readmission rate. RESULTS: Taking 24 h as the critical value, compared with ERCP > 24 h, malignant biliary obstruction as a cause of AC was significantly less common in the ERCP ≤ 24 h group (5.2% vs 11.5%). The proportion of cardiovascular dysfunction (11.2% vs 2.6%), respiratory dysfunction (14.2% vs 5.3%), and ICU admission (11.2% vs 4%) in the ERCP ≤ 24 h group was significantly higher, while the LOHS was significantly shorter (median, 6 d vs 7 d). Stratified by the severity of AC, higher ICU admission was only observed in grade III AC and shorter LOHS was only observed in grade I and II AC. There were no significant differences in 30-d mortality between groups, either in the overall population or in patients with grade I, II or III AC. With 48 h as the critical value, compared with ERCP > 48 h, the proportion of choledocholithiasis as the cause of AC was significantly higher in the ERCP ≤ 48 h group (81.5% vs 68.3%). The ERCP ≤ 48 h group had significantly lower 30-d mortality (0 vs 1.9%) and shorter LOHS (6 d vs 8 d). Stratified by AC severity, lower 30-d mortality (0 vs 6.1%) and higher ICU admission rates (22.2% vs 10.2%) were only observed in grade III AC, and shorter LOHS was only observed in grade I and II AC. In the multivariate analysis, cardiovascular dysfunction and time to ERCP were two independent factors associated with 30-d mortality. CONCLUSION: ERCP ≤ 48 h conferred a survival benefit in patients with grade III AC. Early ERCP shortened the LOHS in patients with grade I and II AC.

Predictive factors of needle-knife pre-cut papillotomy failure in patients with difficult biliary cannulation.

Predictors of needle-knife pre-cut papillotomy (NKP) failure for patients with difficult biliary cannulation has not been reported. Between 2004 and 2016, 390 patients with difficult biliary cannulation undergoing NKP were included in this single-center study. Following NKP, deep biliary cannulation failed in 95 patients (24.4%, NKP-failure group) and succeeded in 295 patients (75.6%, NKP-success group). Patient and technique factors were used to identify the predictors of initial NKP failure. Compared with the NKP-success group, periampullary diverticulum (28.4% vs. 18%, p = 0.028), surgically altered anatomy (13.7% vs. 7.1%, p = 0.049), number of cases performed by less experienced endoscopists, and bleeding during NKP (38.9% vs. 3.4%, p < 0.001), were significantly more frequent in the NKP-failure group. On multivariate analysis, surgically altered anatomy (OR 2.374, p = 0.045), endoscopists' experience (OR 3.593, p = 0.001), and bleeding during NKP (OR 21.18, p < 0.001) were significantly associated with initial failure of NKP. In conclusion, NKP is a highly technique-sensitive procedure, as endoscopists' experience, bleeding during NKP, and surgically altered anatomy were predictors of initial NKP failure.

Risk Factors of Duodenobiliary Reflux-Related Dysfunction of Covered Biliary Metal Stents after Treatment of Duodenal Stricture in Patients with Malignant Biliary and Duodenal Obstruction.

Duodenal obstruction is often accompanied with unresectable malignant distal biliary obstruction in patients who have undergone biliary self-expandable metal stent (SEMS) placement. Duodenobiliary reflux (DBR) is a major cause of recurrent biliary obstruction (RBO) after covered biliary SEMS placement. We analyzed the risk factors for DBR-related SEMS dysfunction following treatment for malignant duodenal obstruction. Sixty-one patients with covered SEMS who underwent treatment for duodenal obstruction were included. We excluded patients with tumor-related stent dysfunction (n = 6) or metal stent migration (n = 1). Fifty-four patients who underwent covered biliary SEMS placement followed by duodenal metal stenting or surgical gastrojejunostomy were included. Eleven patients had DBR-related biliary SEMS dysfunction after treatment of duodenal obstruction. There was no difference between the duodenal metal stenting group and the surgical gastrojejunostomy group. Duodenal obstruction below the papilla of Vater and a score of ≤2 on the Gastric Outlet Obstruction Scoring System after treatment for duodenal obstruction were associated with DBR-related covered biliary SEMS dysfunction. Thus, creating a reliable route for ensuring good oral intake and avoiding DBR in patients with duodenal obstruction below the papilla of Vater are both important factors in preventing DBR-related covered biliary SEMS dysfunction.

Simple and Reliable Method for Gastric Subepithelial Tumor Localization Using Endoscopic Tattooing before Totally Laparoscopic Resection.

BACKGROUND: Totally laparoscopic surgery for early gastric cancer and subepithelial tumors has been popularized worldwide, yet localization of early or small-sized tumors is a persistent challenge due to difficulty being identified with the lack of manual tactile sensation. Thus, accurate localization with tattooing before the surgery would help improve efficiency during surgery. There are multiple methods to localize tumors before laparoscopy, each with varying advantages and disadvantages. The use of endoscopic tattooing with dye has been carried out for several decades due to its safety, lower cost, and convenience. However, there is a lack of studies on endoscopic tattooing before totally laparoscopic resection. AIMS: To evaluate the effect of endoscopic tattooing with dye for gastric subepithelial tumors localization before laparoscopic resection and to evaluate the tattooing effect on different locations of tumors in stomach. METHOD: We retrospectively collected data of patients with gastric subepithelial tumors who underwent endoscopic tattooing before totally laparoscopic resection from 2017 to 2020 in a university affiliated medical center. All patients were analyzed for preoperative characteristics and then categorized into two groups based on tumor locations concerning the difficulty of laparoscopic surgery. The independent t test and Chi-square test were performed to compare perioperative outcome and complications between these two groups. RESULT: A total of 19 patients were included retrospectively at our center. The individuals were 5 male and 14 female patients with a mean age of 58.2 years old. Most patients had no symptoms, and the tumors were found incidentally in 12 patients (63%). All tumors were identified clearly during laparoscopic resection. The mean tumor size was 2.3 cm. The surgeries took an average of 111 min and a mean of 7 mL blood loss was found. All tumors had negative resection margins with no recurrence during follow-up. Gastrointestinal stromal tumor was the major pathologic diagnosis, found in 12 patients (63%), followed by the leiomyoma in 5 patients (26%). Only three patients had mild adverse effects after surgery and the symptoms were self-limited. Our analysis found no significant difference in preoperative patient characteristics and perioperative outcomes between patients with differing tumor locations. CONCLUSION: This study is the first and largest report on endoscopic tattooing with dye before laparoscopic resection of gastric subepithelial tumor resection. Our results emphasize that endoscopic tattooing with dye is a safe and reliable method for localizing subepithelial tumors in the stomach prior to totally laparoscopic resection, with no correlation to where the tumor is located.

Management of biliary diseases after the failure of initial needle knife precut sphincterotomy for biliary cannulation.

Endoscopic retrograde cholangiopancreatography is not always successful even with needle knife precut sphincterotomy (NKPS). How to manage these patients with initial NKPS failure has not been well studied. We report the outcomes of patients who received endoscopic and non-endoscopic rescue treatment after the initial NKPS failure. During the 15 years from 2004 to 2018, 87 patients with initial NKPS failure received interval endoscopic treatment (IET group, n = 43), percutaneous transhepatic biliary drainage (PTBD group, n = 25), or bile duct surgery (BDS group, n = 19) were retrospectively studied. Compared with the PTBD group, the prevalence of choledocholithiasis was higher (69.8% vs. 16.0%, p < 0.001), and malignant bile duct stricture were lower (20.9% vs. 76.0%, p < 0.001) in the IET group. Furthermore, the IET group had a significantly longer time interval between the first and second treatment procedures (4 days vs. 2 days, p = 0.001), a lower technique success rate (79.1% vs. 100%, p = 0.021), and a shorter length of hospital stay (7 days vs. 18 days, p < 0.001). Compared to the BDS group, the only significant finding was that the patients in the IET group were older. Although not statistically significant, the complication rate was lowest in the IET group (7.0%) while highest in the BDS group (15.8%). Complications in the IET group were also mild, as compared with the other two groups. In conclusion, IET should be considered after initial failed NKPS for deep biliary cannulation before contemplating more invasive treatment such as BDS. PTBD may be the alternative therapy for patients with malignant biliary obstruction.

Surgical outcome of Mirizzi syndrome: Value of endoscopic retrograde cholangiopancreatography and laparoscopic procedures.

BACKGROUND: Laparoscopic cholecystectomy (LC) with associated procedures and endoscopic retrograde cholangiopancreatography (ERCP) have been the standard treatments for both common and rare biliary diseases. Mirizzi syndrome (MS) is a rare and complex biliary condition. We report our experience with MS treatment and investigate the value of laparoscopic procedures and ERCP in patient management. METHODS: From 2004 to 2017, 100 consecutive patients with MS were diagnosed by ERCP and underwent surgery in a referral center. Sixty patients were treated with intended LC, and 40 patients were treated with open cholecystectomy (OC). The clinical manifestations, ERCP and associated procedures, surgical procedures, and postoperative outcomes were investigated. RESULTS: The surgical mortality rate was 1%, while the surgical morbidity rate was 15%. The patients treated with intended LC suffered from less morbidity (5%). The percentage of postoperative residual biliary stones was 32% (n = 32), and only three patients underwent re-operation (laparotomy) for stone removal. The laparotomy conversion rate in the intended LC group was 16.7% (10/60). The length of hospitalization for the patients with successful LC was significantly shorter than that for the patients with conversion and intended OC. Csendes classification was a risk factor for conversion from LC to OC (type I vs types II to V, P < .0001). CONCLUSIONS: A combination of a laparoscopic procedure and ERCP may provide therapeutic benefits for patients with MS.

Predicting cholecystocholedochal fistulas in patients with Mirizzi syndrome undergoing endoscopic retrograde cholangiopancreatography.

BACKGROUND: Mirizzi syndrome (MS) is defined as an extrinsic compression of the extrahepatic biliary system by an impacted stone in the gallbladder or the cystic duct leading to obstructive jaundice. Endoscopic retrograde cholangiopancreatography (ERCP) could serve diagnostic and therapeutic purposes in patients with MS in addition to revealing the relationships between the cystic duct, the gallbladder, and the common bile duct (CBD). Cholecystectomy is a challenging procedure for a laparoscopic surgeon in patients with MS, and the presence of a cholecystocholedochal fistula renders preoperative diagnosis important during ERCP. AIM: To evaluate cholecystocholedochal fistulas in patients with MS during ERCP before cholecystectomy. METHODS: From 2004 to 2018, all patients diagnosed with MS during ERCP were enrolled in this study. Patients with associated malignancy or those who had already undergone cholecystectomy before ERCP were excluded. In total, 117 patients with MS diagnosed by ERCP were enrolled in this study. Among them, 21 patients with MS had cholecystocholedochal fistulas. MS was further confirmed during cholecystectomy to check if cholecystocholedochal fistulas were present. The clinical data, cholangiography, and endoscopic findings during ERCP were recorded and analyzed. RESULTS: Gallbladder opacification on cholangiography is more frequent in patients with MS complicated by cholecystocholedochal fistulas (P < 0.001). Pus in the CBD and stricture length of the CBD longer than 2 cm were two additional independent factors associated with MS, as demonstrated by multivariate analysis (odds ratio 5.82, P = 0.002; 0.12, P = 0.008, respectively). CONCLUSION: Gall bladder opacification is commonly seen in patients with MS with cholecystocholedochal fistulas during pre-operative ERCP. Additional findings such as pus in the CBD and stricture length of the CBD longer than 2 cm may aid the diagnosis of MS with cholecystocholedochal fistulas.

Efficacy and Adverse Effects of Self-Expandable Metal Stent Placement for Malignant Duodenal Obstruction: The Papilla of Vater as a Landmark.

PURPOSE: Self-expandable metal stents are used for malignant duodenal obstruction. Outcomes between stents placed above and below the papilla of Vater differ, and no study has investigated these differences. We evaluated the efficacy and adverse events of stent placement in these two locations and reported our experience with self-expandable metal stent placement in patients. PATIENTS AND METHODS: We retrospectively analyzed the data of patients with unresectable metastatic cancers (n = 101), who underwent successful duodenal self-expandable metal stent placement between 2008 and 2018. Patients were divided into above and below the papilla of Vater groups. Patient demographics, technical and clinical outcomes, post-procedural morbidity, and stent patency were analyzed. RESULTS: Overall, 71 and 30 patients had intestinal obstruction above (including the papilla itself) and below the papilla of Vater and underwent successful stenting. Common bile duct obstruction was more common in the above-papilla group. Procedure time was similar between the groups, if an appropriate endoscope could facilitate stent placement in the below-papilla group. Both groups achieved symptomatic relief. Median stent patency duration was not significantly different between the groups; three patients had severe gastrointestinal bleeding due to postoperative vascular-enteric fistula. CONCLUSION: Self-expandable metal stents can effectively relieve symptoms of duodenal obstructions located above and below the papilla of Vater. Duodenoscopes could facilitate stent placement if the obstruction is located below the papilla of Vater; if gastrointestinal bleeding occurs postoperatively, the possibility of vascular-enteric fistula formation should be considered.

Linked-color imaging combined with the NICE classification system for optical diagnosis of colon polyps: new image-enhanced endoscopic technology for pathological prediction.

INTRODUCTION: Linked-color imaging (LCI) is a recently developed system used in endoscopy. It creates clear and bright endoscopic images using short-wavelength, narrow-band laser light combined with white laser light. The illuminating light and signal processing emphasize slight color differences in abnormal regions that approximate the normal color of the mucosa. As a result, regions initially appearing red become a deeper shade of red, while regions originally appearing white become brighter, yet with natural tones. This process facilitates recognition of slight differences in the color of the mucosa and clarifies the boundaries of the mucosal pit. AIM: To determine whether LCI of the colon can improve the correlation between endoscopic findings and pathological diagnosis. METHODS: Consecutive patients who underwent colonoscopy requiring polypectomy or removal by biopsy forceps if possible were recruited. Probable polyp histology was assessed by two endoscopists using the Narrow-band imaging International Colorectal Endoscopic (NICE) classification and LCI data. All detected polyps were sent to the pathology department for pathological diagnosis by two pathologists. RESULTS: In total, 94 polyps were found in 43 patients. The sensitivity, specificity, positive predictive value, and negative predictive value for neoplastic lesion prediction (NICE type2/3) were 96.5%, 83.8%, 90.2%, and 93.9%, respectively. CONCLUSION: LCI combined with the NICE classification system is a powerful tool for predicting probable histology of colon polyps.

Association of endoscopic ultrasonographic parameters and gastrointestinal stromal tumors (GISTs): can endoscopic ultrasonography be used to screen gastric GISTs for potential malignancy?

BACKGROUND: Previous research shows that only 10-30% of gastrointestinal stromal tumors (GISTs) are malignant. Nonetheless, some reports suggest that all of them have some degree of potential for malignancy. Endoscopic ultrasonography (EUS) is a useful technique for differentiation of subepithelial lesions in the gastrointestinal tract. We explored EUS characteristics that might predict the malignancy potential of GISTs. METHODS: In this retrospective review of the medical records from 1999 through 2007, patients who had gastric stromal tumors diagnosed prior to surgery using EUS were enrolled. The EUS images, procedure records and tissue histopathology were reviewed. All patients were positive for C-kit. RESULTS: Of the 110 patients enrolled, 57 were males, and 53 were females. Most (67%) of the GISTs were located in the gastric body. The lesion size ranged from 6.3 to 150 mm (mean ± SD: 39.73 ± 22.49 mm). The high-risk GIST group had 19 (17.3%) patients, the intermediate-risk group had 12 (10.9%) patients and the low/very low-risk group had 79 (71.8%) patients. Thirty patients had cystic lesions (27.3%), while six patients had calcification in the lesion (5.5%). Additionally, 27 patients (24.5%) had surface ulceration visible on endoscopy. GISTs at high risk for malignancy were highly associated with lesion size (p < 0.0001), cystic change (p = 0.015) and surface ulceration (p = 0.036) but not with calcification (p = 0.667). We also found that mitosis was associated with lesion size (p < 0.0001) rather than other parameters. Age was not predictive of malignancy potential (p = 0.316). However, tumor size is the only one independent risk factor for malignancy (p ≤ 0.0001). CONCLUSIONS: The preliminary results show that large gastric GISTs with cystic change and surface ulceration may associate with a risk of malignancy, warranting more aggressive management. Nevertheless, the tumor size is more important than other factors.