This study aimed to determine the prevalence of human epidermal growth factor receptor 2 (HER2)–ultralow breast cancer among cases initially classified as HER2 immunohistochemistry (IHC) 0 and assess interobserver variability in interpreting low-level HER2 expression. Methods: In this multicenter retrospective study, all invasive breast cancer cases diagnosed between January and December 2022 across 10 Korean institutions were retrieved. Institutional pathologists reexamined HER2 IHC slides originally reported as IHC 0 according to the 2018 American Society of Clinical Oncology/College of American Pathologists guidelines and reclassified them as HER2-null (0), HER2-ultralow (0+), or HER2-low (1+). Slides from 10% of HER2-null and HER2-ultralow cases were digitized for central review and independently assessed by two pathologists, with discrepancies resolved by consensus. Results: Among 8,026 cases, 2,836 cases (35.5%) were initially reported as IHC 0. Upon re-review, 1,673 (59.0%), 1,139 (40.2%), and 24 (0.8%) cases were reclassified as HER2-null, HER2-ultralow, and HER2-low, respectively. The prevalence of HER2-ultralow breast cancer varied considerably across institutions (23.7%–78.1%). Central review of 268 digitized cases showed concordance in 193 cases (72.0%). Among the 75 discordant cases, 54 tumors (72.0%) were upgraded from HER2-null to HER2-ultralow, and 18 (24.0%) tumors were upgraded from HER2-ultralow to HER2-low. Furthermore, two tumors (2.7%) were downgraded from HER2-ultralow to HER2-null. Conclusions: Approximately 40% of cases initially categorized as IHC 0 were reclassified as HER2-ultralow. The substantial inter-institutional variability observed in interpreting low-level HER2 expression highlights the need for standardized training and quality assurance to ensure accurate identification of patients eligible for HER2-targeted antibody–drug conjugates.

bjective To analyze the growth trends of height and weight among primary and secondary school students, and explore the developmental characteristics and gender differences at different age groups, and to provide a scientific basis for adolescent health policy formulation. Methods Based on 675 175 health examination records of 227 978 students aged 6-17 years in Shiyan City from 2015 to 2024, a logistic growth model was employed to fit the curves of height and weight changes with age. Results From 2015 to 2024, height and weight showed steady increases across all age groups, exhibiting typical sigmoidal growth patterns. The growth rates varied across age groups: the younger age group (6-9 years) showed a moderate growth (annual height increase of 0.5-1.0 cm, weight increase of 0.03-0.06 kg/year), while the older age group (10-17 years) demonstrated a significant growth (annual height increase of 1.5-2.0 cm, weight increase of 0.22-0.38 kg/year). The growth rate curves displayed a unimodal distribution. The growth inflection points of male students occurred later than that of female students (height inflection point: 9.87 years for males vs. 8.98 years for females; weight inflection point: 10.70 years for males vs. 9.99 years for females). Female students experienced a more concentrated but shorter period of growth and development. The peak height growth rate was 7.40 cm/year at age 9 for females and 7.09 cm/year at age 10 for males, while the peak weight growth rate was 5.04 kg/year at age 10 for females and 5.27 kg/year at age 11 for males. Conclusion The physical development of primary and secondary school students in Shiyan City follows a logistic growth pattern, with significant gender differences and characteristics of adolescent growth spurts. Female students exhibit an earlier and more concentrated growth process.

ObjectiveTo evaluate the efficacy and safety of early intradermal needle therapy in preventing retained products of conception （RPOC） following induced abortion. MethodsA randomized， single-blind， placebo-controlled trial design was applied. Eighty-eight patients scheduled for early induced abortion were randomly assigned to either an intradermal needle group （44 cases） or a sham control group （44 cases）. Both groups underwent ultrasound-guided vacuum aspiration under general anesthesia and received standard postoperative pharmacological care. Immediately following the operation， the intradermal needle group received active intradermal needle therapy at bilateral Sanyinjiao （SP 6）， Hegu （LI 4） and Zhiyin （BL 67）， with needles retaining for 3 days， acupoint pressing three times daily for 5 minutes per acupoint， followed by 5 minutes of walking after each pressing session； while the sham control group received a visually identical， blunt-tipped sham needle intervention. The primary outcome was endometrial thickness measured by Doppler ultrasound at week 2 post-procedure. Secondary outcomes included the incidence of RPOC， visual analog scale （VAS） score and PTSD Checklist-Civilian Version （PCL-C） score at 2 hours post-procedure， volume and duration of vaginal bleeding， uterine volume， Pictorial Blood Loss Assessment Chart （PBAC） scores at weeks 5 and 12， menstrual cycle characteristics， and adverse events should be recorded. ResultsAt week 2 post-procedure， endometrial thickness was significantly lower in the intradermal needle group compared to the sham control group （P＜0.05）. Transvaginal ultrasonography at postoperative week 2 showed thinner endometrium in the intradermal needle group than in the sham group （P＜0.05）. RPOC occurred 1 case （2.27%） in the intradermal needle group versus 9 cases （20.45%） in the sham control group， yielding a significantly higher RPOC incidence in the sham control group （P＜0.05）. Patients in the intradermal needle group had less postoperative vaginal bleeding volume and shorter bleeding duration than those in the sham control group （P＜0.05）. No statistically significant difference was found in 2-hour postoperative VAS pain score， uterine volume at postoperative week 2 and week 5， PBAC score at postoperative week 5 and week 12， or menstrual cycle at postoperative week 12 between groups（all P＞0.05）. No obvious adverse reactions were observed in either group. ConclusionImmediate intradermal needle intervention after early induced abortion can significantly reduce the incidence of postoperative RPOC， exert beneficial effects on reducing the volume and duration of postoperative vaginal bleeding as well as alleviating post-traumatic stress symptoms， with good safety.

Background/Aims: Various lumen-apposing metal stents (LAMS) have been used for the endoscopic ultrasound-guided transmural drainage (EUS-TD) of postoperative pancreatic fluid collections (POPFC) and peripancreatic fluid collections (PFC). In this study, we aimed to assess the efficacy and safety of novel electrocautery-enhanced LAMSs (Hot-Plumber with Z-EUS IT) with different inter-flange lengths (13 to 33 mm) for managing POPFC and PFC. Methods: We reviewed the interventional EUS database of Asan Medical Center to identify consecutive patients with POPFC or PFC who underwent EUS-TD with the novel LAMSs between April 2023 and December 2023. Technical success, clinical success, and adverse events were evaluated. Results: Ten patients (5 with POPFCs and 5 with PFCs) were included in the analysis. The technical and clinical success rates were 100% and 90%, respectively. The LAMS was placed using either the freehand technique (n=5) or the over-the-guide wire technique (n=5). One patient successfully underwent endoscopic necrosectomy for walled-off necrosis through a novel LAMS.Two patients experienced adverse events (one stent migration and one infection). The LAMS was removed in 7 out of 10 patients after resolution of the fluid collection at a median of 61 days (interquartile range, 31 to 69 days) post-LAMS placement. Conclusions EUS-TD using the novel LAMS for POPFC and PFC demonstrated high efficacy and an acceptable safety profile. This novel LAMS represents a viable option when selecting stents for EUS-guided drainage of the POPFC and PFC.

Background: A nationwide Rehabilitation at Home Care Pilot Program for patients undergoing lower extremity orthopedic surgeries has been ongoing since 2020. The program was designed to improve clinical outcomes through early mobilization and rehabilitation after discharge. This study aimed to analyze the interim data to assess its effectiveness and suggest improvements, particularly for older patients who are more vulnerable compared to younger patients. Methods: We analyzed the data of 872 patients from seven hospitals. Patients were divided into an older-age group (OG; ≥60 years) and younger-age group (YG; <60 years). The Berg Balance Scale (BBS) and Numeric Rating Scale (NRS) scores for pain were the main outcomes. Results: Participants were categorized into OG (n=801) and YG (n=71). The most common surgeries were knee joint replacement (63.7%) in OG and hip joint replacement in YG (77.5%). It took more days to enroll in the pilot program in OG (4.4 days) than YG (3.2 days). OG showed less improvement in BBS than YG for all surgeries (23.3 vs. 31.9) and hip joint surgery (19.8 vs. 33.5). In patients with hip joint replacement in OG, those with a higher number of comorbidities (≥3) showed less BBS improvement than those with fewer comorbidities (<3). In the pain domain, NRS scores decreased in both groups. Conclusion The postoperative rehabilitation education program appeared to be effective in improving physical function and reducing pain severity, though the improvement was less obvious in older patients who may require a more comprehensive approach compared to younger patients.

Background: We investigated whether nutritional intake is associated with physical activity (PA) and handgrip strength (HGS) in individuals with airflow limitation. Methods: This study analyzed data from the 2014 and 2016 Korean National Health and Nutrition Examination Survey. We assessed total protein intake (g/day), caloric intake (kcal/day), and other nutritional intakes, using a 24-hour dietary recall questionnaire. HGS was measured three times for each hand using a digital grip strength dynamometer, and PA was assessed as health-enhancing PA. Airflow limitation was defined as a forced expiratory volume/forced vital capacity ratio of 0.7 in individuals over 40 years of age. Participants were categorized into groups based on their PA levels and HGS measurements: active aerobic PA vs. non-active aerobic PA, and normal HGS vs. low HGS. Results: Among the 622 individuals with airflow limitation, those involved in active aerobic PA and those with higher HGS had notably higher total food, calorie, water, protein, and lipid intake. The correlations between protein and caloric intake with HGS were strong (correlation coefficients=0.344 and 0.346, respectively). The forest plots show that higher intakes of food, water, calories, protein, and lipids are positively associated with active aerobic PA, while higher intakes of these nutrients are inversely associated with low HGS. However, in the multivariate logistic regression analysis, no significant associations were observed between nutritional intake and active aerobic PA or HGS. Conclusion Nutritional intake was found to not be an independent factor associated with PA and HGS. However, the observed correlations suggest potential indirect effects that warrant further investigation.

Ulcerative colitis （UC）， which is characterized by a complex and multifactorial etiology， remains one of the challenging disorders in the international field of digestive system diseases. In recent years， rectal administration preparations have made rapid progress in UC therapeutic applications. This study systematically reviews the dosage forms， mechanisms of action， and clinical applications of rectally-administered preparations for the treatment of UC. It is found that suppositories are the most commonly used dosage forms for rectal administration. The newer suppositories have the advantages of high bioavailability and good stability. Enemas can retain the drug in the intestine as much as possible to achieve the effects of diluting intestinal toxins， cleansing the bowel， and reducing inflammation. Gels can achieve a drug-sustained-release effect and effectively improve intestinal mucosal damage. The mechanism of action of this type of preparation is mainly to inhibit inflammatory cell infiltration， regulate intestinal microbial homeostasis， and increase the expression of tight-junction proteins， so as to play anti-inflammatory， regulate the intestinal bacterial flora， repair the intestinal mucosa， and other efficacies. The diversity of rectal administration forms provides a wide range of choices for the clinical treatment of UC， such as Mesalazine suppositories， Lianshao enemas， and temperature- sensitive gels loaded with drugs for UC.

Background and Objectives: Hearing loss significantly affects communication, psychosocial well-being, and quality of life. This study analyzes the National Health Insurance Service database to assess the trends and characteristics of hearing loss in South Korea from 2010 to 2020.Subjects and Method The database encompasses 97% of the Korean population, providing comprehensive data on medical history, prescriptions, and health examinations. The analysis used the World Health Organization’s ICD-10 definitions to categorize hearing loss types and examine their prevalence and incidence across various demographics over 11 years. Results: There was an overall annual increase of 4.62% in diagnosed cases of hearing loss, with the most significant rise among the elderly. The rate of increase accelerated from 3.32% between 2010 and 2014 to 6.49% between 2014 and 2020, corresponding with the improved hearing aid access facilitated by policy changes. Women showed a slightly higher increase than men. The data also indicated a consistent rise in abnormal hearing test results during health examinations, especially in older adults. Conclusion The study highlights an increasing trend in hearing loss diagnoses, driven by an aging population and enhanced detection facilitated by policy changes. These findings emphasize the need for continuous monitoring and targeted health policies to manage hearing loss effectively, offering valuable insights for global health management and policy development.

Background and Objectives: This study aims to analyze trends in hearing disability and the use of hearing rehabilitation devices (hearing aids and cochlear implants) in South Korea over the past 11 years (2010-2020) using data from the National Health Insurance Service (NHIS).Subjects and Method Data were extracted from the NHIS database, covering approximately 97% of the South Korean population. Patients diagnosed with hearing loss were classified using ICD-10 codes. The data were analyzed to determine trends in hearing disability, hearing aid prescriptions, and cochlear implant usage by age, gender, and types and causes of hearing loss. Results: The number of hearing disability patients increased from 170900 in 2010 to 362738 in 2020, with an annual growth rate of 7.95%. The highest increase was observed in the ≥60 age group, with an annual growth rate of 11.04%. Hearing aid prescriptions rose from 4966 in 2010 to 11974 in 2020, showing a 10.45% annual increase. Females showed a higher growth rate in both hearing disability and hearing aid prescriptions compared to males. Cochlear implant prescriptions also increased, particularly among older adults. Conclusion The study highlights a significant rise in hearing disability and the use of hearing aids and cochlear implants in South Korea, especially among the elderly. The findings underscore the importance of early diagnosis and intervention for hearing loss and the need for policy improvements to enhance accessibility and affordability of hearing rehabilitation services. Additional strategies are needed to ensure appropriate hearing rehabilitation for those not yet receiving adequate care.