Kim SJ, et al. J Korean Med Sci. 2019 Aug;34(35):e231. https://doi.org/10.3346/jkms.2019.34.e231

Background: Increasing clarithromycin resistance has led to changes in several guidelines for treatment of Helicobacter pylori infections. We compared the H. pylori eradication rates of the empirical concomitant therapy (CoT) and a tailored therapy (TaT) using dual-priming oligonucleotide-based polymerase chain reaction to detect mutations in the 23S rRNA gene that are related to clarithromycin resistance. Methods: Between June 2020 and May 2021, 290 patients were enrolled and randomly assigned to 2 groups. In the CoT group, the patients received rabeprazole 20 mg, amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg twice daily for 14 days. In the TaT group, point mutation-negative patients received rabeprazole 20 mg, amoxicillin 1 g, and clarithromycin 500 mg twice daily for 14 days and point mutation-positive patients received rabeprazole 20 mg twice daily, metronidazole 500 mg thrice daily, and bismuth 120 mg and tetracycline 500 mg 4 times daily for 14 days. Results: A total of 290 and 261 patients were included in the intention-to-treat (ITT) and per-protocol (PP) analyses, respectively. A2142G and/or A2143G point mutations were identified in 28.6% of the patients. No significant difference in eradication rates were observed between the 2 groups as per ITT (CoT, 82.8% and TaT, 85.5%, P = .520) and PP (CoT, 88.6% and TaT, 94.6%, P = .084) analyses. In point mutation-positive patients, the eradication rates in the CoT group were lower than those in the TaT group as per ITT (69.8% and 87.5%, respectively, P = .050) and PP (76.9% and 97.1%, respectively, P = .011) analyses. Conclusion: CoT and TaT showed similar overall eradication rates for H. pylori. However, CoT eradication rate was suboptimal, especially in point mutation-positive patients.

Background: Suspicion of lesions and prediction of the histology of esophageal cancers or premalignant lesions in endoscopic images are not yet accurate. The local feature selection and optimization functions of the model enabled an accurate analysis of images in deep learning. Objectives: To establish a deep-learning model to diagnose esophageal cancers, precursor lesions, and non-neoplasms using endoscopic images. Additionally, a nationwide prospective multicenter performance verification was conducted to confirm the possibility of real-clinic application. Methods: A total of 5162 white-light endoscopic images were used for the training and internal test of the model classifying esophageal cancers, dysplasias, and non-neoplasms. A no-code deep-learning tool was used for the establishment of the deep-learning model. Prospective multicenter external tests using 836 novel images from five hospitals were conducted. The primary performance metric was the external-test accuracy. An attention map was generated and analyzed to gain the explainability. Results: The established model reached 95.6% (95% confidence interval: 94.2–97.0%) internal-test accuracy (precision: 78.0%, recall: 93.9%, F1 score: 85.2%). Regarding the external tests, the accuracy ranged from 90.0% to 95.8% (overall accuracy: 93.9%). There was no statistical difference in the number of correctly identified the region of interest for the external tests between the expert endoscopist and the established model using attention map analysis (P = 0.11). In terms of the dysplasia subgroup, the number of correctly identified regions of interest was higher in the deep-learning model than in the endoscopist group, although statistically insignificant (P = 0.48). Conclusions: We established a deep-learning model that accurately classifies esophageal cancers, precursor lesions, and non-neoplasms. This model confirmed the potential for generalizability through multicenter external tests and explainability through the attention map analysis.

Endoscopic submucosal dissection (ESD) is considered the treatment of choice for early gastric cancer (EGC) with a negligible risk of lymph node metastasis. Locally recurrent lesions on artificial ulcer scars are difficult to manage. Predicting the risk of local recurrence after ESD is important to manage and prevent the event. We aimed to elucidate the risk factors associated with local recurrence after ESD of EGC. Between November 2008 and February 2016, consecutive patients (n = 641; mean age, 69.3 ± 9.5 years; men, 77.2%) with EGC who underwent ESD at a single tertiary referral hospital were retrospectively analyzed to evaluate the incidence and factors associated with local recurrence. Local recurrence was defined as the development of neoplastic lesions at or adjacent to the site of the post-ESD scar. En bloc and complete resection rates were 97.8% and 93.6%, respectively. The local recurrence rate after ESD was 3.1%. The mean follow-up period after ESD was 50.7 ± 32.5 months. One case of gastric cancer-related death (0.15%) was noted, wherein the patient had refused additive surgical resection after ESD for EGC with lymphatic and deep submucosal invasion. Lesion size ≥15 mm, incomplete histologic resection, undifferentiated adenocarcinoma, scar, and the absence of erythema of the surface were associated with a higher risk of local recurrence. Predicting local recurrence during regular endoscopic surveillance after ESD is important, especially in patients with a larger lesion size (≥15 mm), incomplete histologic resection, surface changes of scars, and no erythema of the surface.

AIM: To compare the success rates and adverse events of early needle-knife fistulotomy (NKF) and double-guidewire technique (DGT) in patients with repetitive unintentional pancreatic cannulations. METHODS: From a total of 1650 patients admitted for diagnostic or therapeutic endoscopic retrograde cholangiopancreatography (ERCP) at a single tertiary care hospital (Pusan National University Yangsan Hospital, Yangsan, South Korea) between January 2009 and December 2012, 134 (8.1%) patients with unsuccessful biliary cannulation after 5 min trial of conventional methods, together with 5 or more repetitive unintentional pancreatic cannulations, were enrolled in the study. Early NKF and DGT groups were assigned 67 patients each. In the DGT group, NKF was performed for an additional 7 min if successful cannulation was not achieved. RESULTS: The success rates with early NKF and the DGT were 79.1% (53/67) and 44.8% (30/67) (P < 0.001), respectively. The incidence of post-ERCP pancreatitis (PEP) was lower in the early NKF group than in the DGT group [4.5% (3/67) vs 14.9% (10/67), P = 0.041]. The mean cannulation times in the early NKF and DGT groups after assignment were 257 s and 312 s (P = 0.013), respectively. CONCLUSION: Our data suggest that early NKF should be considered as the first approach to selective biliary cannulation in patients with repetitive unintentional pancreatic cannulations.