Purpose: This study analyzed the pathological complete response (pCR) rates, long-term outcomes, and biological features of human epidermal growth factor receptor 2 (HER2)-zero, HER2-low, and HER2-positive breast cancer patients undergoing neoadjuvant treatment. Methods: This single-center study included 1,667 patients who underwent neoadjuvant chemotherapy from 2008 to 2014. Patients were categorized by HER2 status, and their clinicopathological characteristics, chemotherapy responses, and recurrence-free survival (RFS) rates were analyzed. Results: Patients with HER2-low tumors were more likely to be older (p = 0.081), have a lower histological grade (p < 0.001), and have hormone receptor (HorR)-positive tumors (p < 0.001). The HER2-positive group exhibited the highest pCR rate (23.3%), followed by the HER2-zero (15.5%) and HER2-low (10.9%) groups. However, the pCR rate did not differ between HER2-low and HER2-zero tumors in the HorR-positive or HorR-negative subgroups.The 5-year RFS rates increased in the following order: HER2-low, HER2-positive, and HER2-zero (80.0%, 77.5%, and 74.5%, respectively) (log-rank test p = 0.017). A significant survival difference between patients with HER2-low and HER2-zero tumors was only identified in HorR-negative tumors (5-year RFS for HER2-low, 74.5% vs. HER2-zero, 66.0%; log-rank test p-value = 0.04). Multivariate survival analysis revealed that achieving a pCR was the most significant factor associated with improved survival (hazard ratio [HR], 4.279; p < 0.001).Compared with HER2-zero, the HRs for HER2-low and HER2-positive tumors were 0.787 (p = 0.042) and 0.728 (p = 0.005), respectively. After excluding patients who received HER2-targeted therapy, patients with HER2-low tumors exhibited better RFS than those with HER2-zero (HR 0.784, p = 0.04), whereas those with HER2-positive tumors exhibited no significant difference compared with those with HER2-low tumors (HR, 0.975; p = 0.953). Conclusion Patients with HER2-low tumors had no significant difference in pCR rate compared to HER2-zero but showed better survival, especially in HorR-negative tumors.Further investigation into biological differences is warranted.

Background: and Purpose We aimed to determine the proportion of Korean patients with early Alzheimer’s disease (AD) who are eligible to receive lecanemab based on the United States Appropriate Use Recommendations (US AUR), and also identify the barriers to this treatment. Methods: We retrospectively enrolled 6,132 patients with amnestic mild cognitive impairment or mild amnestic dementia at 13 hospitals from June 2023 to May 2024. Among them, 2,058 patients underwent amyloid positron emission tomography (PET) and 1,199 (58.3%) of these patients were amyloid-positive on PET. We excluded 732 patients who did not undergo brain magnetic resonance imaging between June 2023 and May 2024. Finally, 467 patients were included in the present study. Results: When applying the criteria of the US AUR, approximately 50% of patients with early AD were eligible to receive lecanemab treatment. Among the 467 included patients, 36.8% did not meet the inclusion criterion of a Mini-Mental State Examination (MMSE) score of ≥22. Conclusions Eligibility for lecanemab treatment was not restricted to Korean patients with early AD except for those with an MMSE score of ≥22. The MMSE criteria should therefore be reconsidered in areas with a higher proportion of older people, who tend to have lower levels of education.

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: Since 1995, the Korean Gastric Cancer Association (KGCA) has been periodically conducting nationwide surveys on patients with surgically treated gastric cancer. This study details the results of the survey conducted in 2023. Materials and Methods: The survey was conducted from March to December 2024 using a standardized case report form. Data were collected on 86 items, including patient demographics, tumor characteristics, surgical procedures, and surgical outcomes. The results of the 2023 survey were compared with those of previous surveys. Results: Data from 12,751 cases were collected from 66 institutions. The mean patient age was 64.6 years, and the proportion of patients aged ≥71 years increased from 9.1% in 1995 to 31.7% in 2023. The proportion of upper-third tumors slightly decreased to 16.8% compared to 20.9% in 2019. Early gastric cancer accounted for 63.1% of cases in 2023.Regarding operative procedures, a totally laparoscopic approach was most frequently applied (63.2%) in 2023, while robotic gastrectomy steadily increased to 9.5% from 2.1% in 2014.The most common anastomotic method was the Billroth II procedure (48.8%) after distal gastrectomy and double-tract reconstruction (51.9%) after proximal gastrectomy in 2023.However, the proportion of esophago-gastrostomy with anti-reflux procedures increased to 30.9%. The rates of post-operative mortality and overall complications were 1.0% and 15.3%, respectively. Conclusions The results of the 2023 nationwide survey demonstrate the current status of gastric cancer treatment in Korea. This information will provide a basis for future gastric cancer research.

This review summarized the results of clinical trials in 2024 that were believed to have a significant impact on clinical practice in the field of gynecologic oncology. The SHAPE trial, INTERLACE and KEYNOTE-A18 trials, and BEATcc and COMPASSION-16 trials were included in early-stage, locally advanced, and recurrent/metastatic cervical cancer, respectively. For uterine corpus cancer, updated survival data of the four trials (NRG-GY018, RUBY, AtTEnd, DUO-E) for endometrial cancer and the first survival data of LMS-04 trial for leiomyosarcoma were described. For ovarian cancer, the final overall survival results of PRIMA study were followed by DUO-O, ATHENA-combo, and FIRST-ENGOT-OV44 trial in different disease conditions. Finally, the results of DESTINY-PanTumor02, a basket trial of trastuzumab deruxtecan, were briefly addressed.

We updated the Korean Society of Gynecologic Oncology (KSGO) practice guideline for the management of ovarian cancer as version 5.1. The ovarian cancer guideline team of the KSGO published announced the fifth version (version 5.0) of its clinical practice guidelines for the management of ovarian cancer in December 2023. In version 5.0, the selection of the key questions and the systematic reviews were based on the data available up to December 2022.Therefore, we updated the guidelines version 5.0 with newly accumulated clinical data and added 5 new key questions reflecting the latest insights in the field of ovarian cancer between 2023 and 2024. For each question, recommendation was provided together with corresponding level of evidence and grade of recommendation, all established through expert consensus.

Purpose: The career ladder system is a pivotal strategy for securing excellent nurses. The aim of this study is to understand hospital nurses’ experiences of participating in the career ladder system and to explore the essence of this system. Methods: In February 22 to March 3, 2022, nurses employed at a general hospital in South Korea were selected for this study using snowball and purposive sampling. Data were collected from interviews with three focus groups, the compositions of which are as follows: group 1, 6 participants; group 2, 5 participants; and group 3, 6 participants. All interviews were recorded, transcribed verbatim, and subsequently analyzed using qualitative research methods. Results: The following six categories were derived under the overall theme of “the arduous journey to discovering a nurse’s true name”: (1) rites of passage to becoming the ideal nurse; (2) unexpected challenges in the promotion preparation process; (3) biased criteria for evaluating nursing competencies; (4) unclear changes in roles and perceptions after promotion; (5) self-discovered pride and fulfillment as a nurse; and (6) the unspoken struggles of evaluators. Conclusion The findings suggest that the career ladder system fosters nurses’ professional growth and self-actualization. However, for effective implementation, nurses’ deep understanding and systematic management of the career ladder system are essential. This study offers valuable insights and benchmarks for healthcare institutions aiming to adopt the system.

South Korea’s current vaccination policies leave a surveillance gap for non-National Immunization Program (NIP) vaccines. In this study, we proposed a sentinel surveillance approach for monitoring the safety of non-NIP vaccines. Vaccination data were collected retrospectively among patients hospitalized with pre-defined adverse events of special interest (AESI) by reviewing electronic medical records in five university hospitals. This approach incorporates expert assessment to determine the causal relationship. We confirmed that 16 patients had received non-NIP vaccines among 860 patients diagnosed with AESI.We concluded one case of preeclampsia was possibly related to tetanus-diphtheria-pertussis vaccination. We propose a multi-hospital-based, retrospective assessment system for predefined AESIs as an alternative to active vaccine safety monitoring method. These efforts are expected to enhance both the accuracy and timeliness of safety monitoring in South Korea.

Background: Because of the low prevalence of inherited retinal diseases, reports on the distribution of retinitis pigmentosa (RP)-related genes in Korean patients are scarce. The aim of this study was to determine the mutation spectrum and allele frequency and observe the final diagnoses in a Korean cohort clinically diagnosed with RP. Methods: We used whole-exome sequencing (WES) to analyze a Korean cohort of 100 unrelated patients clinically diagnosed with RP. The possible pathogenicity of each variant was assessed based on the guidelines of the American College of Medical Genetics and Genomics and Association for Molecular Pathology, in-silico prediction tools, known clinical phenotypes, and inheritance patterns. Results: Definite causative genes were detected in 60/100 patients (60.0%). Of these 60 cases, USH2A was the most common causative gene (14/60, 23.3%), followed by EYS (13/60, 21.7%) and RP1 (6/60, 10.0%). The clinical diagnosis was redefined in 9 of the 60 probands (15.0%) with causative genes after WES. Five of the 60 patients (8.3%) carried a causative variant in CHM, and the clinical diagnosis was redefined as choroideremia. Leber congenital amaurosis was diagnosed in 2/60 probands (3.3%), and RDH12 and RPGRIP1 were the causative genes in each patient. One patient (1/60, 1.7%) was diagnosed with Bietti’s crystalline dystrophy, with CYP4V2 identified as the causative gene. In another patient (1/60, 1.7%), ABCA4 variants were detected with clinical findings suggestive of cone-rod dystrophy. Conclusion This study reports the mutational spectrum of a cohort of Korean patients with a clinical diagnosis of RP who were referred for genetic testing. This study adds valuable data regarding the frequency of genes as well as their relation to the age of symptom onset and relation to other inherited retinal degenerations.