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.

Coronary artery bypass grafting (CABG) remains a key revascularization strategy for ischemic heart disease; however, nationwide trends in the Republic of Korea have not been thoroughly investigated. Using data from the Korean National Health Insurance Service, we analyzed adult patients who underwent isolated CABG between 2005 and 2022. We evaluated surgical volume, patient demographics, procedural strategies (off-pump vs. onpump), and outcomes. International comparisons were conducted using national cardiac surgery registry data. A total of 51,923 CABG cases were identified. Annual surgical volume declined until 2013 but gradually increased thereafter, reaching 3,717 cases in 2022. Despite this recovery, Korea’s per capita CABG rate remains among the lowest worldwide.In contrast, more than 60% of procedures were performed off-pump—the highest rate worldwide. Over time, the average patient age and prevalence of diabetes increased, whereas in-hospital mortality showed a modest decline. Compared with other countries, the Republic of Korea demonstrated a uniquely low procedural volume and a strong preference for off-pump CABG. This nationwide analysis highlights Korea’s distinctive CABG practice patterns and provides valuable insights for optimizing future clinical and policy decisions in cardiac surgical care.

Purpose: This study aimed to examine the effect of nurse clinical educators’ coaching leadership on the nursing performance of novice and advanced beginner nurses, and to verify the mediating role of grit in this relationship. Methods: A descriptive cross-sectional survey was conducted among 142 nurses with less than 36 months of clinical experience at three general hospitals in D city, South Korea. Data were collected from June 20 to July 5, 2025, using self-reported online questionnaires measuring coaching leadership, grit, and nursing performance. Statistical analyses included descriptive statistics, correlation analysis, and a mediation analysis using PROCESS macro Model 4. Results: Coaching leadership was positively associated with both grit and nursing performance. Grit was also positively correlated (r=.71, p<.001) with nursing performance and was found to partially mediate (β=.30, 95% CI=0.20, 0.41) the relationship between coaching leadership and nursing performance. The findings indicate that coaching leadership not only directly enhances nursing performance but also indirectly improves it by increasing the nurses’ grit. Conclusion Nurse clinical educators’ coaching leadership directly and indirectly enhanced the nursing performance of novice and advanced beginner nurses through the mediation of grit. Strengthening the coaching leadership competencies of nurse clinical educators and implementing educational programs that foster grit among early-career nurses may optimize nursing performance.

Background: Although patients with malignant melanoma in situ (MIS) have a high survival rate, a risk of recurrence or upstaging remains. Thus, a comprehensive understanding of its prognosis is essential for optimal patient management. Objective: To investigate the clinical characteristics and survival outcomes of Korean patients with MIS. Methods: We retrospectively analyzed the medical records and photographs of patients with MIS treated at a single tertiary center between 2008 and 2021. Clinical features, including diagnosis, treatment, recurrence, and mortality, were examined. Results: A total of 156 patients with MIS were included, with a mean age of 59.3 years. The most common subtype was acral lentiginous melanoma (80.8%). Delayed diagnosis was associated with subungual MIS (SUMis; p ＜0.05). Among the subtypes other than SUMis, 77.3% met three or more of the ABCD criteria for melanoma.Hutchinson’s sign was observed in 67.3% of cases of SUMis. Ulceration was present in only two cases (1.3%).Recurrence occurred in nine patients (5.8%), with four (2.6%) experiencing relapse after 5 years. Upstaging was observed in two patients (1.3%) due to intralymphatic or regional nodal metastasis occurring at 19 and 10 months post-treatment. The 5-year and 10-year melanoma-specific/overall survival rates were 100.0/96.9% and 100.0/89.0%, respectively. Conclusion Although the survival rates of patients with MIS are high, long-term and close follow-up after treatment is essential because of the possibility of late recurrence and rare instances of intralymphatic or regional nodal metastasis. Additionally, the presence of clinical ulceration is highly suggestive of invasive melanoma.

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.

The efficacy of clarithromycin-containing triple therapy (TT) against Helicobacter pylori has declined in Korea, with recent first-line eradication rates falling below 70%. Clarithromycin resistance exceeded 30%, undermining the standard regimen for H. pylori. These trends necessitate a change in the treatment strategy. This review analyzed the shift proposed in the draft of the 2025 Korean H. pylori guidelines. We examined the rationale for abandoning TT as a first-line empirical therapy and the establishment of a new dual-pillar strategy: 1) the declining role of clarithromycin-containing TT as a first-line treatment and 2) polymerase chain reaction (PCR)-based tailored therapy as the recommended precision approach. We explored the 1) emergence of new empirical regimen options, 2) application of tailored therapy, and 3) adoption of potassium-competitive acid blockers (P-CABs). Empirical regimens have shifted toward four-drug combinations to achieve higher cure rates. Concomitant therapy (proton-pump inhibitor [PPI] or P-CAB+amoxicillin+clarithromycin+metronidazole) offers high efficacy but raises concerns about antibiotic overuse. As a compromise, bismuth-augmented triple regimens (adding bismuth to TT) are now recommended; these modified quadruple therapies (e.g., PACB: PPI+amoxicillin+clarithromycin+bismuth, or PAMB: PPI+amoxicillin+metronidazole+bismuth) significantly improve eradication rates without requiring a third antibiotic class. Regarding tailored therapy, PCR-based domestic clinical research data consistently achieves ≥90% cure rates in first-line treatment—markedly higher than empirical TT in Korea. Economic analyses supported the cost-effectiveness of this approach. The guideline algorithm for salvage therapy was clarified. Bismuth quadruple therapy has been confirmed as the standard second-line treatment. For third-line therapy, we analyzed the efficacy of levofloxacin-based regimens, rifabutin-based therapy, and bismuth add-on therapy with two previously unused antibiotics. The 2025 Korean guidelines establish quadruple therapies as the new standard through a dual strategy: pragmatic empirical treatment and PCR-guided tailored therapy, with P-CABs and bismuth-based regimens as key components.

Purpose: To investigate indicators of dry eye disease that influence punctal plug loss. Methods: A retrospective review was conducted on patients who received SuperFlex® punctal plugs. To analyze the relationship between punctal plug loss and markers for dry eye, patients were categorized into a loss group, defined as those who experienced unintended loss within 3 months of insertion, and a retention group. In total, 11 indicators were compared between the two groups, including meibomian gland expressibility, cloudiness of meibomian gland secretions, telangiectasis of the eyelid margin, tear osmolarity, Schirmer’s test value, the expression levels of matrix metalloproteinase-9 in tears, NEI/Industry grading system score, Sjögren’s International Collaborative Clinical Alliance ocular staining score, tear lipid layer thickness (LLT), and meiboscore. Results: In all, 47 eyes of 30 patients were included in the study. Of these, 16 eyes (34%) were assigned to the loss group. Meibomian gland expressibility grade was significantly higher in the loss group (1.60 ± 0.58) compared to the retention group (1.04 ± 0.37, p = 0.0247). Additionally, LLT was significantly lower in the loss group (58.7 ± 17.0 nm vs. 88.4 ± 17.6 nm, p = 0.0303). However, no significant correlations were found between punctal plug loss and other indicators of dry eye. Conclusions Worse meibomian gland expressibility and thinner LLT are associated with a higher rate of punctal plug loss.

Objectives: Osteoporosis is a silent disease with low screening rates in many developing countries. This study aimed to evaluate the feasibility of using an artificial intelligence (AI)-based system to screen osteoporosis from pelvic and hip radiographs in Vietnam. Methods: We conducted a cross-sectional study at a tertiary medical center in Central Vietnam in 2023. A total of 2000 consecutive pelvic and hip radiographs from patients aged ≥ 40 years were collected. After excluding poorquality images, 1987 radiographs were analyzed using an AI-based software designed to estimate bone mineral density (BMD) from plain radiographs and derive T-scores. Osteoporosis was defined as a T-score ≤ − 2.5. Patient characteristics, radiographic findings, and risk factors for osteoporosis were analyzed. Results: Among 1987 patients (mean age 66.4 ± 15.1 years; 41.3% men), osteoporosis was identified in 872 patients (43.9%). The prevalence increased with age and was higher in women than in men (58.7% vs 22.8%, P < 0.001). Osteoporosis was associated with femoral neck (OR = 3.8, 95% CI: 2.7–5.2) and intertrochanteric fractures (OR = 7.0, 95% CI: 4.5–11.0). Patients with lower T-scores had a higher risk of hip fractures, especially those with T-scores ≤ − 3.0 (OR = 11.5, 95% CI: 5.5–24.5). Conclusions AI-based analysis of pelvic and hip radiographs is a feasible and effective tool for osteoporosis screening in Vietnam. The prevalence of osteoporosis in this hospital-based setting was high, particularly among elderly women.AI-assisted screening may offer an accessible strategy for early detection of osteoporosis in resource-limited settings.

Purpose: This study analyzed the characteristics of pediatric patients’ (≤ 18 years) intentional injury-related visits to the emergency department (ED) using National Emergency Department Information System data from January 1 through December 31, 2023, providing foundational evidence for prevention strategies and policy development. Methods: The injuries were categorized into unintentional and intentional, and relevant characteristics were compared between the 2 categories. The intentional injuries were further divided into self-harm and violence. Percentages were calculated for each variable and compared using the chi-square or Fisher exact tests. Results: Among 301,852 pediatric patients, those with intentional injuries showed higher proportions of girls, adolescents, visits in the wee hours, visits via firehouse ambulances, injuries by collision, by penetration, or by poisoning, hospitalization, Korean Triage and Acuity Scale levels 1-3, an ED length of stay of 2 hours or longer, and primary care by psychiatrists, than those with unintentional injuries. The pediatric patients with self-harm injuries showed higher proportions of girls, adolescents, visits in the wee or morning hours, visits via firehouse ambulances, injuries by collision, by penetration, or by poisoning, hospitalization or inter-facility transfer, Korean Triage and Acuity Scale levels 1-3, an ED length of stay of 2 hours or longer, and primary care by psychiatrists as well as by orthopedic surgeons or pediatricians, than those with violence injuries. Conclusion This study highlights the need to develop strategies per age and sex for preventing self-harm among pediatric patients, and to ensure safe and effective psychiatric care in EDs. In addition, the prevention of child abuse requires a multidisciplinary approach that includes preventive education programs, mandatory reporting in EDs, and the adoption of screening tools such as the Finding Instrument for Non-accidental Deeds.