Purpose: Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research. Materials and Methods: Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes.Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes. Results: Data from 5,460 ESD cases from 5,250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days. Conclusions This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.

The Wikstroemia genus is highly regarded in traditional Asian medicine for its diverse therapeutic applications, including the treatment of inflammatory and infectious conditions. Among its members,Wikstroemia trichotoma (Thunb.) Makino remains a promising medicinal resource which is yet to be chemicallycharacterized. To ensure the chemical consistency of W. trichotoma, we developed and validated the first HPLC method for the simultaneous quantification of three major marker compounds: chlorogenic acid (1), miconioside B (2), and matteucinol 7-O-apiofuranosyl(1→6)-glucopyranoside (3). Chromatographic separation was achieved on a C18 column using a gradient elution system of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. Detection was optimized using a photodiode array (PDA) detector at 280 and 325 nm, based on the absorption maxima of the markers. The method was validated in accordance with the International Council for Harmonisation (ICH) and the Ministry of Food and Drug Safety (MFDS) guidelines. The results demonstrated high linearity (r2 > 0.999), with limits of detection and quantitation ranging from 4.28–6.42 and 12.97–19.47 μg/ mL, respectively. Intra- and inter-day precision (% RSD ≤ 1.83%) and accuracy (recoveries of 92.5–101.7%) were within acceptable limits. Quantitative analysis revealed the contents of 1, 2, and 3 in the W. trichotoma extract to be 19.9, 139.8, and 264.9 mg/g, respectively. This study provides a reliable analytical framework for the standardization, quality control, and future pharmacological evaluation of W. trichotoma.

Purpose: While the benefit of neoadjuvant chemotherapy (NAC) has been established in human epidermal growth factor receptor 2 (HER2)-positive and triple-negative breast cancers, its effectiveness in achieving pathological complete response (pCR) and optimal patient selection in estrogen receptor (ER)-positive, HER2-negative breast cancers remain less clearly defined. This study aimed to identify immunohistochemistry (IHC)-based predictors of pCR and to develop a scoring model for ER-strong positive/HER2-negative breast cancer. Methods: Data from a prospective cohort were retrospectively analyzed. We included 522 patients with ER-strong positive/HER2-negative tumors who received NAC and surgery between 2008 and 2021. IHC markers including progesterone receptor (PR), Ki-67, epidermal growth factor receptor (EGFR), cytokeratin 5/6 (CK5/6), and p53 were evaluated to identify predictors of pCR. Independent predictors of pCR from multivariate logistic regression were used to develop a weighted 4-point model. Model performance was assessed using receiver operating characteristic analysis. The prognostic impact of pCR was evaluated using KaplanMeier and Cox regression analyses. Results: Independent predictors of pCR included PR-negative status, positivity for basallike markers (EGFR or CK5/6), and Ki-67 ≥ 50%. The scoring model demonstrated good discrimination for pCR (area under the curve = 0.754). pCR rates increased stepwise, with scores of 4.9% (low), 10.7% (intermediate), and 36.2% (high). In the high-score group, pCR was significantly associated with improved disease-free survival (hazard ratio [HR], 0.09; p = 0.023) and distant metastasis-free survival (HR, 0.11; p = 0.035), whereas no significant survival differences according to pCR status were observed in the low and intermediate score groups. Conclusion This IHC-based model predicts pCR and helps identify subgroups in which pCR is associated with meaningful survival benefit following NAC in ER-positive/HER2-negative breast cancers. High-scoring patients may benefit from NAC, while patients with low- or intermediatescores may be better managed with surgery and endocrine therapy. This model may support personalized treatment decisions regarding NAC.

Purpose: Lobular carcinoma In Situ (LCIS) is a noninvasive lesion associated with an increased risk of invasive cancer. Since its removal from the tumor, node, metastasis classification in the 8th edition of the American Joint Committee on Cancer (AJCC) guidelines, the clinical management of LCIS has shifted from surgery to surveillance. However, studies focusing on the risk and associated factors for invasive cancer development in pure LCIS without ductal carcinoma In Situ (DCIS) or invasive cancer remain limited. Methods: We retrospectively analyzed 106 patients diagnosed with pure LCIS between 2008 and 2018. This study evaluated the effect of tamoxifen use and histologic type on the development of invasive cancer. Results: All 106 patients underwent surgery, and nine (8.5%) developed invasive cancer over a median follow-up of 67.5 months. The incidence of invasive cancer was lower in the tamoxifen group (6.3%, n = 4) than in the non-tamoxifen group (11.9%, n = 5), although this difference was not statistically significant (p = 0.266). Pleomorphic LCIS had a significantly higher incidence of invasive cancer (30.0%, n = 3) than classic LCIS (6.3%, n = 6) (p = 0.045).Multivariable Cox regression analysis showed no significant difference in the risk of invasive cancer according to tamoxifen use (hazard ratio [HR], 2.031; 95% confidence interval [CI], 0.544–7.579; p = 0.292). However, pleomorphic LCIS showed a trend toward an increased risk of invasive cancer compared to classic LCIS (HR, 3.856; 95% CI, 0.922–16.126; p = 0.064). Conclusion Postoperative tamoxifen did not significantly lower invasive cancer development in patients with pure LCIS. Pleomorphic LCIS may carry a higher risk than classic LCIS. These findings require tailored follow-up and treatment strategies based on the histologic subtype of LCIS.

Objectives: Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research. Methods: Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes. Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes. Results: Data from 5460 ESD cases from 5250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days. Conclusions This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.

Objectives: This study was performed to evaluate the utilization patterns of acid suppressants following the withdrawal of ranitidine in Korea. Methods: Health Insurance Review & Assessment Service (HIRA) data from January 2016 to May 2023 were utilized to assess the usage of histamine H2 receptor antagonists (H2RAs) and proton pump inhibitors (PPIs) for acid-related diseases. Drug utilization was calculated for each agent based on the defined daily dose (DDD). To evaluate changes in utilization following the ranitidine recall, an interrupted time series analysis was conducted using segmented linear regression and an autoregressive integrated moving average model. Results: Before the withdrawal of ranitidine, the DDD per 100 000 inhabitants per day was increasing by 6.9 (95% confidence interval [CI], 4.7 to 9.0) for H2RAs and by 19.3 (95% CI, 16.9 to 21.8) for PPIs each month. After the recall, H2RA utilization immediately declined by -1041.7 (95% CI, -1115.8 to -967.7), followed by a monthly increase of 6.6 (95% CI, 3.7 to 9.6) above the previous trend. PPI utilization temporarily surged by 235.2 (95% CI, 149.1 to 321.3), then displayed a monthly increase of 4.1 (95% CI, 0.7 to 7.6) on top of the pre-recall trend. Among PPIs, esomeprazole and rabeprazole demonstrated notable increases, representing the most commonly used acid suppressants in 2023. Conclusions PPI usage rose prominently following the withdrawal of ranitidine from the market. Considering the potential adverse effects of PPIs, further research is necessary to evaluate the public health implications of shifts in the utilization of acid suppressants.

Background: s/Aims: Liver transplantation (LT) is now a critical, life-saving treatment for patients with liver cirrhosis or hepatocellular carcinoma. Despite its significant benefits, biliary complications (BCs) continue to be a major cause of postoperative morbidity.This study evaluates the fluorescence intensity (FI) of the common bile duct (CBD) utilizing near-infrared indocyanine green (ICG) imaging, and examines its association with the incidence of BCs within three months post-LT. Methods: This investigation analyzed data from nine living donor LT (LDLT) recipients who were administered 0.05 mg/kg of ICG prior to bile duct anastomosis. Real-time perfusion of the CBD was recorded for three minutes using an ICG camera, and FI was quantified using Image J (National Institutes of Health). Key parameters assessed included F max, F1/2 max, T1/2 max, and the slope (F max/ T max) to evaluate the fluorescence response. Results: BCs occurred in two out of nine patients. These two patients exhibited the longest T1/2 max values, which were linked with lower slope values, implicating a potential relationship between extended T1/2 max, reduced slope, and the occurrence of postoperative BCs. Conclusions The study indicates that ICG fluorescence imaging may serve as an effective tool for assessing bile duct perfusion in LDLT patients. While the data suggest that an extended T1/2 max and lower slope may correlate with an increased risk of BCs, further validation through larger studies is required to confirm the predictive value of ICG fluorescence imaging in this setting.

Background: s/Aims: Liver transplantation (LT) is now a critical, life-saving treatment for patients with liver cirrhosis or hepatocellular carcinoma. Despite its significant benefits, biliary complications (BCs) continue to be a major cause of postoperative morbidity.This study evaluates the fluorescence intensity (FI) of the common bile duct (CBD) utilizing near-infrared indocyanine green (ICG) imaging, and examines its association with the incidence of BCs within three months post-LT. Methods: This investigation analyzed data from nine living donor LT (LDLT) recipients who were administered 0.05 mg/kg of ICG prior to bile duct anastomosis. Real-time perfusion of the CBD was recorded for three minutes using an ICG camera, and FI was quantified using Image J (National Institutes of Health). Key parameters assessed included F max, F1/2 max, T1/2 max, and the slope (F max/ T max) to evaluate the fluorescence response. Results: BCs occurred in two out of nine patients. These two patients exhibited the longest T1/2 max values, which were linked with lower slope values, implicating a potential relationship between extended T1/2 max, reduced slope, and the occurrence of postoperative BCs. Conclusions The study indicates that ICG fluorescence imaging may serve as an effective tool for assessing bile duct perfusion in LDLT patients. While the data suggest that an extended T1/2 max and lower slope may correlate with an increased risk of BCs, further validation through larger studies is required to confirm the predictive value of ICG fluorescence imaging in this setting.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Objectives: This study was performed to evaluate the utilization patterns of acid suppressants following the withdrawal of ranitidine in Korea. Methods: Health Insurance Review & Assessment Service (HIRA) data from January 2016 to May 2023 were utilized to assess the usage of histamine H2 receptor antagonists (H2RAs) and proton pump inhibitors (PPIs) for acid-related diseases. Drug utilization was calculated for each agent based on the defined daily dose (DDD). To evaluate changes in utilization following the ranitidine recall, an interrupted time series analysis was conducted using segmented linear regression and an autoregressive integrated moving average model. Results: Before the withdrawal of ranitidine, the DDD per 100 000 inhabitants per day was increasing by 6.9 (95% confidence interval [CI], 4.7 to 9.0) for H2RAs and by 19.3 (95% CI, 16.9 to 21.8) for PPIs each month. After the recall, H2RA utilization immediately declined by -1041.7 (95% CI, -1115.8 to -967.7), followed by a monthly increase of 6.6 (95% CI, 3.7 to 9.6) above the previous trend. PPI utilization temporarily surged by 235.2 (95% CI, 149.1 to 321.3), then displayed a monthly increase of 4.1 (95% CI, 0.7 to 7.6) on top of the pre-recall trend. Among PPIs, esomeprazole and rabeprazole demonstrated notable increases, representing the most commonly used acid suppressants in 2023. Conclusions PPI usage rose prominently following the withdrawal of ranitidine from the market. Considering the potential adverse effects of PPIs, further research is necessary to evaluate the public health implications of shifts in the utilization of acid suppressants.