Although oxidative stress is the main pathophysiology of the development of diabetic neuropathy, oral administration of antioxidants has given disappointing results. Here, we hypothesized that local delivery of antioxidants would provide protective effects on Schwann cells due to the high concentration of local lesions. We prepared alpha-tocopherol (ATF)-loaded liposomes and tested their skin penetration after sonication. An in vitro study using IMS-32 cells was conducted to determine the level of reactive oxygen species (ROS) scavenging effects of ATF-liposomes. ATF reduced ROS in high-glucose-exposed IMS-32 cells in a dosedependent manner. ATF-liposomes also reduced the ROS level in vitro and ultrasound irradiation enhanced delivery to the dermis in porcine ear skin. This study showed that it is feasible to deliver ATF through the skin and can effectively reduce ROS. This model is worthy of development for clinical use.

Background: Gestational diabetes mellitus (GDM) affects women with diverse pathological phenotypes, but little is known about the effects of this variation on perinatal outcomes. We explored the metabolic phenotypes of GDM and their impact on adverse pregnancy outcomes. Methods: Women diagnosed with gestational glucose intolerance or GDM were categorized into subgroups according to their prepregnancy body mass index (BMI) and the median values of the gestational Matsuda and Stumvoll indices. Logistic regression analysis was employed to assess the odds of adverse pregnancy outcomes, such as large-for-gestational age (LGA), small-for-gestational age, preterm birth, low Apgar score, and cesarean section. Results: A total of 309 women were included, with a median age of 31 years and a median BMI of 22.3 kg/m2. Women with a higher pre-pregnancy BMI had a higher risk of LGA newborns (adjusted odds ratio [aOR] for pre-pregnancy BMI ≥25 kg/m2 compared to 20–23 kg/m2, 4.26; 95% confidence interval [CI], 1.99 to 9.12; P<0.001; P for trend=0.001), but the risk of other adverse pregnancy outcomes did not differ according to pre-pregnancy BMI. Women with insulin resistance had a higher risk of LGA (aOR, 1.88; 95% CI, 1.02 to 3.47; P=0.043) and cesarean section (aOR, 2.12; 95% CI, 1.29 to 3.50; P=0.003) than women in the insulin-sensitive group. In contrast, defective β-cell function did not affect adverse pregnancy outcomes. Conclusion Different metabolic phenotypes of GDM were associated with heterogeneous pregnancy outcomes. Women with obesity and those with insulin resistance are at greater risk of adverse outcomes and might need strict glycemic management during pregnancy.

Purpose: This study evaluated the postoperative quality of life (QoL) after various types of gastrectomy for gastric cancer. Materials and Methods: A multicenter prospective observational study was conducted in Korea using the Korean Quality of Life in Stomach Cancer Patients Study (KOQUSS)-40, a new QoL assessment tool focusing on postgastrectomy syndrome. Overall, 496 patients with gastric cancer were enrolled, and QoL was assessed at 5 time points: preoperatively and at 1, 3, 6, and 12 months after surgery. Results: Distal gastrectomy (DG) and pylorus-preserving gastrectomy (PPG) showed significantly better outcomes than total gastrectomy (TG) and proximal gastrectomy (PG) with regard to total score, indigestion, and dysphagia. DG, PPG, and TG also showed significantly better outcomes than PG in terms of dumping syndrome and worry about cancer. Postoperative QoL did not differ significantly according to anastomosis type in DG, except for Billroth I anastomosis, which achieved better bowel habit change scores than the others. No domains differed significantly when comparing double tract reconstruction and esophagogastrostomy after PG. The total QoL score correlated significantly with postoperative body weight loss (more than 10%) and extent of resection (P<0.05 for both).Reflux as assessed by KOQUSS-40 did not correlate significantly with reflux observed on gastroscopy 1 year postoperatively (P=0.064). Conclusions Our prospective observation using KOQUSS-40 revealed that DG and PPG lead to better QoL than TG and PG. Further study is needed to compare postoperative QoL according to anastomosis type in DG and PG.

Purpose: The novel curability criteria for elderly (EL) patients have been proposed to stratify their risk of lymph node metastasis (LNM), following non-curative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). Hence, this study aimed to evaluate the effectiveness of the EL criteria and compare them with those of the well-known eCura system. Materials and Methods: A retrospective analysis was performed on 143 patients who did not meet the curative ESD criteria at a tertiary hospital in Korea between 2011 and 2022. Of these, 102 underwent additional surgery, while 41 were followed up without further treatment. The LNM rates based on the EL and eCura systems were stratified and compared. Results: In the surgery group, 29.4% (30/102) patients were classified as EL-low (EL-L) and 70.2% (72/102) as EL-high (EL-H). The LNM rates (95% confidence interval) were 0.0% (0.0–11.6) and 9.7% (4.0–19.0) for EL-L and EL-H, respectively (P=0.102). EL-L was closely aligned with the eCura low-risk category, with a similar patient proportion (32.4%) and an LNM rate of 0.0% (0.0–10.6). The eCura system classified 94.1% (48/51) of the EL-L patients as lowrisk, with an 86% concordance rate (123/143). Discordant cases included patients with positive vertical margins, but without other risk factors, who were classified as EL-H without LNM. Conclusions Patients with EL-L showed no LNM, and the EL criteria demonstrated high concordance with the eCura system. The EL criteria may be as effective as the eCura system in identifying low-risk patients after non-curative ESD for EGC.

Purpose: The optimal reconstruction method following distal gastrectomy has not been elucidated. Since Billroth-II (B-II) reconstruction is commonly associated with increased bile reflux, Braun jejunojejunostomy has been proposed to reduce this complication. Materials and Methods: We retrospectively analyzed 325 patients with gastric cancer who underwent distal gastrectomy with B-II reconstruction between January 2015 and December 2017, comprising 159 patients without Braun anastomosis and 166 with Braun anastomosis.Outcomes were assessed over three years using annual gastroscopy based on the residual food, gastritis, and bile reflux criteria and the Los Angeles classification for reflux esophagitis. Results: In the first postoperative year, the group with Braun anastomosis showed a significant reduction in bile reflux compared to the group without Braun anastomosis (75.9% vs. 86.2%; P=0.019). Moreover, multivariate analysis identified Braun anastomosis as the sole factor associated with this outcome. Additionally, the group with Braun anastomosis had a lower incidence of heartburn (12.0% vs. 20.1%; P=0.047) and reduced use of prokinetics (P<0.001) and acid reducers (P=0.002) compared to the group without Braun anastomosis.However, these benefits diminished in subsequent years, with no significant differences in residual food, gastritis, or reflux esophagitis between the groups. Both groups showed similar body mass index scores and nutritional outcomes over the 3-year follow-up period. Conclusions Although Braun anastomosis offers short-term benefits in reducing bile reflux after B-II reconstruction, these effects are not sustainable. The routine use of Braun anastomosis should be reconsidered, though either approach remains a viable option depending on the patient’s circumstances.

Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area.Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version.Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Background: Tinnitus is a multifactorial condition with no universally accepted assessment guidelines. The Korean Tinnitus Study Group previously established consensus statements on the definition, classification, and diagnostic tests for tinnitus. As a continuation of this effort, this study aims to establish expert consensus on tinnitus assessment and treatment outcome evaluation, specifically tailored to the Korean clinical context. Methods: A modified Delphi method involving 26 otology experts from across Korea was used. A two-round Delphi survey was conducted to evaluate statements related to tinnitus assessment before and after treatment. Statements were rated on a scale of 1 to 9 for the level of agreement. Consensus was defined as ≥ 70% agreement (score of 7–9) and ≤ 15% disagreement (score of 1–3). Statistical measures such as content validity ratio and Kendall’s coefficient of concordance (W) were calculated to assess agreement levels. Results: Of the 46 assessment-related statements, 17 (37%) reached consensus, though overall pre-treatment assessments showed weak agreement (Kendall’s W = 0.319). Key areas of agreement included the use of the visual analogue scale, numeric rating scale, and validated questionnaires for pre-treatment evaluation. Five statements, such as the use of computed tomography, magnetic resonance imaging, and angiography for diagnosing pulsatile tinnitus, achieved over 90% agreement. For treatment outcome measurements, 8 of 12 statements (67%) reached a consensus, with moderate agreement (Kendall’s W = 0.513). Validated questionnaires and psychoacoustic tests were recommended for evaluating treatment effects within 12 weeks. While standardized imaging for pulsatile tinnitus and additional clinical tests were strongly recommended, full consensus was not achieved across all imaging modalities. Conclusion This study provides actionable recommendations for tinnitus assessment and treatment evaluation, emphasizing the use of standardized tools and individualized approaches based on patient needs. These findings offer a practical framework to enhance consistency and effectiveness in tinnitus management within Korean clinical settings.

Background: Primary Merkel cell carcinoma of the salivary gland is currently not listed in the World Health Organization classification. However, cases of Merkel cell type neuroendocrine carcinomas of the salivary gland with perinuclear cytokeratin 20 positivity have been intermittently reported. We here investigated the clinicopathologic features of additional cases. Methods: Data of four cases of Merkel cell type small cell neuroendocrine carcinoma of the salivary gland were retrieved. To confirm the tumors’ primary nature, clinical records and pathologic materials were reviewed. Optimal immunohistochemical staining was performed to support the diagnosis. Results: All tumors were located in the parotid gland. Possibilities of metastasis were excluded in all cases through a meticulous clinicopathological review. Tumor histology was consistent with the diagnosis of small cell neuroendocrine carcinoma. Tumors’ immunohistochemical phenotypes were consistent with Merkel cell carcinoma, including Merkel cell polyomavirus large T antigen positivity in two of the four cases. Conclusions Merkel cell carcinomas can originate in salivary glands and are partly associated with Merkel cell polyomavirus infection as in cutaneous Merkel cell carcinomas.

The introduction of anti-amyloid therapies for Alzheimer’s disease (AD), such as lecanemab (Lequembi®), which was recently approved in Korea, necessitates careful monitoring for amyloid-related imaging abnormalities (ARIA) using brain MRI. To optimize ARIA monitoring in Korean clinical settings, the Korean Society of Neuroradiology (KSNR) and the Age and Neurodegeneration Imaging (ANDI) Study Group proposed MRI protocol recommendations on essential MR sequences, MRI acquisition parameters, timing and condition of MRI examinations, and essential details to provide a scientific basis for maximizing the safety and efficacy of AD treatment. A customized, standardized MRI protocol focusing on Korea’s healthcare environment can improve ARIA management and ensure patient safety through early detection of potential anti-amyloid therapy side effects, thereby enhancing treatment quality.