Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

The prevalence of prediabetes has steadily increased in Korea, driven by rising obesity rates and lifestyle changes. A structured lifestyle modification program has been shown to significantly reduce the prevalence of diabetes among adults with prediabetes, with this effect sustained over time. Lifestyle modifications including medical nutrition, exercise, and behavioral psychological therapy are effective for preventing and managing diabetes, with medical nutrition therapy playing a crucial role. This study reviews the latest academic guidelines and medical nutrition therapy for diabetes prevention and to introduce the KDPS-hLSM (Korean Diabetes Prevention Study hospital-based lifestyle modification).

Background: Kelch-like ECH-associated protein 1 (KEAP1)–nuclear factor erythroid- 2-related factor 2 (NRF2) pathway is a major regulator protecting cells from oxidative and metabolic stress. Studies have revealed that this pathway is involved in mediating resistance to cytotoxic chemotherapy and immunotherapy; however, its implications in oncogene-addicted tumors are largely unknown. This study aimed to elucidate whether this pathway could be a potential therapeutic target for epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer. Methods: We measured the baseline expression of NRF2 using EGFR-mutant parental cells and acquired gefitinib resistant cells. We investigated whether NRF2 inhibition affected cell death in vitro and tumor growth in vivo using a xenograft mouse model, and compared the transcriptional changes before and after NRF2 inhibition. Results: Baseline NRF2 expression was enhanced in PC9 and PC9 with gefitinib resistance (PC9/GR) cells than in other cell lines, with a more prominent expression in PC9/ GR. The NRF2 inhibitor induced NRF2 downregulation and cell death in a dose-dependent manner. Cotreatment with an NRF2 inhibitor enhanced osimertinib-induced cell death in vitro, and potentiated tumor growth inhibition in a PC9/GR xenograft model. Finally, RNA sequencing revealed that NRF2 inhibition resulted in the altered expression of multiple genes involved in various signaling pathways. Conclusion We identified that NRF2 inhibition enhanced cell death and inhibited tumor growth in tyrosine kinase inhibitor (TKI)-resistant lung cancer with EGFR-mutation. Thus, NRF2 modulation may be a novel therapeutic strategy to overcome the resistance to EGFR-TKIs.

Background/Aims: Serum gastrin levels may be elevated following proton pump inhibitor (PPI) therapy. We aim to elucidate the predictors for the development of hypergastrinemia in maintenance treatment for mild gastroesophageal reflux disease (GERD) using a half-dose PPI. Methods: This study analyzed data from a prospective randomized trial to compare continuous versus on-demand maintenance treatment modalities in patients with mild GERD. Age, sex, body mass index, Helicobacter pylori infection, serum gastrin levels, pepsinogen (PG) I/II ratios, total days of PPI intake, and weight-based PPI dosage (mg/kg) were evaluated. Results: Data from 293 patients who completed a randomized trial were analyzed (continuous group, n = 147 vs on-demand group, n = 146). In univariate analysis, age (P < 0.001), H. pylori infection (P = 0.012), baseline gastrin levels (P < 0.001), and baseline PG ratios (P = 0.016) significantly correlated with post-treatment gastrin levels. In multivariate analysis, age, baseline gastrin levels, and baseline PG ratios were independently associated with final serum gastrin levels. In univariate analysis, age (P = 0.018), H. pylori infection (P = 0.028), baseline gastrin levels (P = 0.011), and baseline PG ratios (P = 0.031) significantly correlated with the development of hypergastrinemia. In multivariate analysis, age, baseline gastrin levels, and baseline PG ratios were independently associated with the development of hypergastrinemia. Conclusion Old age, high baseline serum gastrin levels, and low baseline PG ratios are significant predictors of the development of hypergastrinemia in maintenance treatment for mild GERD using a half-dose PPI.

Background/Aims: Fexuprazan, a novel potassium-competitive acid blocker, was developed for treating acid-related disorders. Pharmacokinetic and pharmacodynamic properties of fexuprazan, unlike those of proton pump inhibitors, are independent of food effect. This study aims to evaluate differences in efficacy and safety of fexuprazan in patients with erosive esophagitis (EE) according to the timing of dosing. Methods: In this multicenter, open-label noninferiority study, patients who had typical reflux symptoms with endoscopically confirmed EE were randomized 1:1 to receive fexuprazan 40 mg daily 30 minutes before or after meal. Treatment was completed after 2 weeks or 4 weeks when healing was endoscopically confirmed. The primary endpoint was the proportion of patients with healed EE confirmed by endoscopy up to week 4. Safety endpoints included treatment-emergent adverse events (TEAEs). Results: In the prior-to-meal group (n = 89) and after-meal group (n = 86), 4-week EE healing rates were 98.77% and 100.00% (difference, 0.01%; 95% CI, –0.01% to 0.04%) and 2-week EE healing rates were 95.77% and 97.14% (difference, 0.01%; 95% CI, –0.05% to 0.07%), respectively. TEAEs were 9.78% and 8.70% in the prior-to-meal group and the after-meal group, respectively. Conclusions Non-inferiority analysis revealed that taking fexuprazan after meal was non-inferior to taking fexuprazan before meals in patients with EE. The frequency of adverse events was similar between the 2 study groups. The drug is safe and effective for healing EE regardless of the timing of dosing.

Background: This study analyzed the status of community-based practice in public healthcare institutions in Korean medical schools and identified related needs. Methods: We conducted an online cross-sectional survey in which 32 of 40 medical schools (80.0%) participated between March and April 2023. We developed questionnaire items aimed at ascertaining the status and perceptions of community-based practice and analyzed the response data using frequency analysis, the Mann-Whitney U test, and content analysis with word clouds. Results: Of the 32 medical schools analyzed, 23 (71.9%) offered practical courses, and of those, 12 (52.2%) implemented practice lessons within courses. Among 20 schools, 18 (90.0%) required students to complete practical courses and over 50% offered these courses in the third and fourth years of the clerkship phase. Perceptions of community practice showed no significant differences based on whether courses were offered. Many schools have proposed that practice should be a continuous curricular element from the premedical to medical years. The primary challenges facing community-based practice were identified as faculty development, collaboration, and compensation of practice institutions. The following words were extracted from the respondents’ comments: practice, community, institution, student, education, faculty, university, and public. Conclusion This study identified the limitations of community-based education provided by Korean medical schools and we report findings that highlight areas of improvement. Notable among these is the need to continuously incorporate community-based practice into medical education while engaging in discussions and conducting research toward developing a comprehensive and systematic curriculum.

Background: Patients with diabetes are known to be at high risk for end-stage kidney disease (ESKD), but the accurate annual risk data for new-onset ESKD is still limited. In South Korea, the prevalence and incidence of ESKD are increasing more rapidly compared to the global average. This study aimed to determine the incidence rate (IR) of ESKD by diabetes status from 2012 to 2022. Methods: Using data from the Korean National Health Insurance Service, we calculated the IR and hazard ratio (HR) for newonset ESKD in the general population. Individuals were categorized based on diabetes status into nondiabetes, impaired fasting glucose (IFG), diabetes duration <5 and ≥5 years. Results: Among the participants, 67.6% were nondiabetic, 22.3% had IFG, and 10% had diabetes. In Korea, the IRs of ESKD were 139 per million population (pmp) for nondiabetes, 188 pmp for IFG, 632 pmp for diabetes <5 years, and 3,403 pmp for diabetes ≥5 years. An advanced estimated glomerular filtration rate (eGFR) category was the strongest risk factor for ESKD development. However, even in patients with normal renal function, those with long-standing diabetes had a 14-fold higher risk of ESKD compared to nondiabetic individuals. The risk of ESKD associated with diabetes increased exponentially with declining renal function. Notably, IFG showed an increasing tendency for ESKD in younger patients (<65 years) with early-stage chronic kidney disease (CKD; eGFR ≥60 mL/min/1.73 m²). Conclusion Longer diabetes duration amplifies ESKD risk, particularly as renal function declines. Even in patients with normal renal function, long-standing diabetes significantly increases ESKD risk, while IFG is associated with elevated risk only in younger individuals with early-stage CKD.

Background: Antithyroid drug (ATD) treatment is the preferred initial treatment for Graves’ disease (GD) in South Korea, despite higher treatment failure rates than radioactive iodine (RAI) therapy or thyroidectomy. This study aimed to evaluate the incidence of treatment failure associated with the primary modalities for GD treatment in real-world practice. Methods: We included 452,001 patients diagnosed with GD between 2004 and 2020 from the Korean National Health Insurance Service-National Health Information Database. Treatment failure was defined as switching from ATD, RAI, or thyroidectomy treatments, and for ATD specifically, inability to discontinue medication for over 2 years. Results: Mean age was 46.2 years, with females constituting 70.8%. Initial treatments for GD included ATDs (98.0%), thyroidectomy (1.3%), and RAI (0.7%), with a noted increment in ATD application from 96.2% in 2004 to 98.8% in 2020. During a median follow- up of 8.5 years, the treatment failure rates were 58.5% for ATDs, 21.3% for RAI, and 2.1% for thyroidectomy. Multivariate analysis indicated that the hazard ratio for treatment failure with ATD was 2.81 times higher than RAI. RAI treatments ≥10 mCi had 37% lower failure rates than doses <10 mCi. Conclusion ATDs are the most commonly used for GD in South Korea, followed by thyroidectomy and RAI. Although the risk of treatment failure for ATD is higher than that of RAI therapy, initial RAI treatment in South Korea is relatively limited compared to that in Western countries. Further studies are required to evaluate the cause of low initial RAI treatment rates in South Korea.

Background/Aims: Magnifying endoscopy with narrow-band imaging (ME-NBI) enables the visualization of detailed microsurface (MS) and microvascular (MV) structures in the gastrointestinal tract. White globe appearance (WGA) is a small whitish lesion with a globular shape identified during ME-NBI for early gastric cancer (EGC). This study aimed to investigate the associations between WGA, clinicopathological characteristics, and other ME-NBI findings in patients with EGC. Methods: The presence or absence of WGA in 122 patients (126 lesions) with an endoscopic diagnosis of EGC who underwent ME-NBI before endoscopic or surgical resection was prospectively collected and retrospectively analyzed. During ME-NBI, the MS and MV patterns and the presence of WGA and white opaque substances (WOS) were investigated. EGC cases were categorized as differentiated or undifferentiated type, and mucosal, submucosal, or advanced. Results: Of 126 lesions, WGA was observed in 25 (19.8%). WGA was associated with tumor size (≤2 cm [17/63, 27.0%] vs >2 cm [8/63, 12.7%]; p=0.044), histologic type differentiated type [22/89, 24.7%] vs undifferentiated type [3/37. 8.1%]; p=0.033), and tumor location (upper third [1/11, 9.1%] vs middle third [18/58, 31.0%] and lower third [6/57, 10.5%]; p=0.017). Although WGA was observed more frequently in lesions with an oval/tubular MS pattern, a fine-network MV pattern, and the absence of WOS, the difference was not statistically significant (MS pattern, p=0.358; MV pattern, p=0.212; WOS, p=0.121, respectively). Conclusions WGA was associated with small tumor size, differentiated-type histology, and middle-third tumor location, and was more frequently observed in lesions with an oval/tubular MS and fine-network MV patterns and the absence of WOS.

Purpose: Many studies using a common data model (CDM) have recently been reported. This study aims to determine the prevalence and clinical characteristics of vancomycin-associated adverse drug reactions (ADRs) using CDM and to identify its usefulness in ADRs. Methods: This study was conducted from the OMOP-CDM (Observational Medical Outcomes Partnership-CDM) version 5.3 database of Convergence Medical Institute of Technology, Pusan National University Hospital. The study cohort was defined as patients who had taken vancomycin for more than 7 days and had normal blood tests within 1 week before administration. ADRs included neutropenia, eosinophilia, thrombocytopenia, drug-induced liver injury, and acute kidney injury. Results: The most frequent ADR to vancomycin was thrombocytopenia (18.32%), followed by neutropenia (7.81%), acute kidney injury (5.85%), eosinophilia (5.32%), and drug-induced liver injury (4.15%). The baseline hematologic values were closer to the reference value of ADR definition in patients who developed ADRs than those without ADRs, even though the values were within the normal range. Acute kidney injury was common in males and the patients had high vancomycin trough concentrations. The period of vancomycin exposure was longer in the ADR groups. The incidence of new adverse reactions was highest for thrombocytopenia, and it was higher in males than in females, except for neutrophilia. Conclusion This study examined the prevalence, incidence rates, and clinical features of vancomycin-associated ADR using CDM. A CDM could serve as a significant data source for monitoring ADRs.