Purpose: Neoadjuvant chemotherapy (NAC) significantly revolutionized the management of locally advanced breast cancer, especially in human epidermal growth factor receptor 2 (HER2)-positive and triple-negative subtypes. However, its effectiveness is limited in estrogen receptor (ER)-positive, HER2-negative breast cancer. This study investigates the clinical response and prognosis of ER-positive, HER2-negative breast cancer after NAC. Methods: The clinicopathological characteristics and treatment responses of 149 patients with ER-positive, HER2-negative breast cancer treated with NAC and surgery at The Catholic University of Korea, Seoul St. Mary’s Hospital between 2018 and 2023 were retrospectively analyzed. Pathologic complete response (pCR) was defined as the absence of invasive tumors (ypT0/is, ypN0). Disease-free survival (DFS) and overall survival (OS) were analyzed using Kaplan-Meier methods, stratified by age (≤50 years vs. >50 years). Results: Among 149 patients, 13 (8.7%) achieved pCR, 87 (58.4%) attained partial responses, 40 (26.8%) had stable disease, and 9 (6.0%) experienced progressive disease. RECIST responses differed significantly by age (P = 0.003). DFS (P = 0.011) and OS (P = 0.005) were significantly associated with clinical response in patients aged ≤50 years. Post-NAC Ki-67 was associated with DFS (P = 0.013) but not OS (P = 0.083) in patients aged ≤50 years. Clinical responses and post-NAC Ki-67 were not associated with DFS (P = 0.544) or OS (P = 0.569) in patients aged >50 years. Conclusion In ER-positive, HER2-negative breast cancer, clinical responses and post-NAC Ki-67 were significant prognostic factors in patients aged ≤50 years but not in older patients. These findings highlight the need for tailored therapeutic approaches that consider age-specific prognostic differences.

Purpose: Radiotherapy (RT) remains a cornerstone of curative treatment for localized and locally advanced prostate cancer. However, dose escalation to improve tumor control is often constrained by the proximity of the rectum, which increases the risk of gastrointestinal (GI) and genitourinary toxicities. Biodegradable rectal spacers inserted between the prostate and rectum have emerged as an effective approach to reduce rectal radiation exposure. This guideline provides evidence-based recommendations on indications, contraindications, procedural standards, and clinical management for biodegradable rectal spacer insertion during prostate cancer RT. Materials and Methods: This guideline was developed by a multidisciplinary expert panel through a systematic review of the literature, analysis of international guidelines (National Comprehensive Cancer Network, European Association of Urology, American Society for Radiation Oncology), and expert consensus among radiation oncologists, radiologists, and urologists with clinical experience in spacer insertion. The strength of each recommendation and the level of evidence were classified according to the modified GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system. Results: Spacer insertion is conditionally recommended (Grade C, Level I) for patients receiving definitive external-beam RT without rectal invasion. It reduces the high-dose rectal irradiation volume (V70–75) by >50%, decreases acute GI toxicity, and helps maintain bowel-related quality of life. However, the benefit for late severe toxicity (grade 2 or higher) remains debated in recent meta-analyses. Contraindications include rectal invasion, anatomical inaccessibility, infection, and material hypersensitivity. Procedures should be performed under local anesthesia in a sterile environment by trained physicians. Short-course antibiotics and simulator-based training, including completion of multiple supervised cases, are advised. Conclusion Biodegradable rectal spacer insertion is clinically validated and effective in reducing acute rectal toxicity. Although pivotal trials demonstrated a favorable procedural safety profile, real-world postmarket data include reports of rare but severe procedural complications. This guideline provides standardized recommendations tailored to Korean clinical practice while remaining consistent with international standards, emphasizing the importance of operator training and careful patient selection.

Objective: : To identify sex-specific risk factors for postoperative urinary retention (POUR) in patients undergoing spine surgery with total intravenous anesthesia (TIVA) and explore differences between male and female patients. Methods: : A retrospective chart review was conducted on 446 adult patients (268 males, 178 females) who underwent spine surgery with TIVA from January 1, 2019 to December 31, 2023. Propensity score matching was applied to adjust for confounding variables, resulting in 328 matched patients (164 males and 164 females). Multivariable logistic regression analyses were performed to identify independent risk factors for POUR. Residual urine volume ≥300 mL was used to define POUR. Results: : Male patients had a higher incidence of POUR compared to female patients. Significant risk factors for POUR in males included myelopathy (adjusted odds ratio [aOR], 5.17; 95% confidence interval [CI], 1.11–24.15), benign prostatic hyperplasia (BPH) (aOR, 2.63; 95% CI, 1.02–6.78), and prolonged anesthesia time ≥240 minutes (aOR, 2.54; 95% CI, 1.13–5.72). No significant risk factors were found in female patients. Myelopathy and prolonged anesthesia were associated with an increased risk of POUR across the overall population. Conclusion : Male sex, myelopathy, BPH, and prolonged anesthesia time are significant risk factors for POUR following spine surgery with TIVA. Given these findings, particular attention should be paid to myelopathy, a history of BPH, and anesthesia time in male patients.

Spinal melanocytoma (SMC) is a rare, slow-growing tumor arising from melanocytes in the spinal cord. We report a patient with a cervical intra- and extradural spinal tumor causing progressive weakness and numbness. On magnetic resonance imaging (MRI), the lesion showed intense homogeneous enhancement, similar to that seen in common neurogenic spinal tumors. After complete resection, pathological examination confirmed melanocytoma. A review of previously reported cases identified 26 reports of this tumor in the cervical spine, most of which were treated with complete surgical resection. Gross total resection is the preferred treatment, although radiation therapy may be considered when residual tumor remains. We report a 25-year-old male patient who presented with progressive weakness and numbness in both the upper and lower extremities for 3 months. MRI showed homogeneous enhancement. The mass compressed the spinal cord at C6–7 and extended through the neural foramen. Based on the MRI findings, spinal schwannoma was suspected preoperatively. Surgical resection was performed with laminectomy, durotomy, and right facetectomy. A dark-colored mass with well-demarcated margins was exposed and removed. Postoperative MRI confirmed complete removal of the mass. The patient recovered well, and his preoperative myelopathic symptoms gradually improved. SMC is a rare benign tumor that may be mistaken for schwannoma. The treatment of choice is gross total resection.

Background and Objectives: We evaluated 20-year trends in heart failure (HF) epidemiology in Korea to quantify changes in its burden from 2002 to 2023. Methods: A nationwide analysis was conducted using a random 50% sample from the Korean National Health Information Database linked to mortality records (2002–2023). HF was defined using diagnostic codes recorded as a primary or secondary condition. We calculated crude and age-standardized rates of prevalence, incidence, hospitalization, and mortality. Survival was assessed using the Kaplan–Meier method, stratified by inpatient versus outpatient diagnosis.Trends in heart transplantation and left ventricular assist device implantations were also examined. Results: By 2023, approximately 1,750,228 individuals had HF (3.41% prevalence). The age-standardized prevalence has more than doubled from 2002 to 2023. The crude incidence increased over time; the age-standardized incidence remained stable in men and declined in women.Hospitalization rates for any cause or secondary HF diagnoses have increased substantially, whereas primary HF hospitalization rates have remained relatively stable. The annual mortality rate in patients with HF was approximately 6.0% in 2023, being markedly higher in older adults.Although short-term survival has improved, particularly in hospitalized patients, long-term survival remains limited. Use of advanced therapies significantly increased. Conclusions The burden of HF in Korea has increased substantially over the past two decades, driven primarily by population aging and improved survival rather than increasing age-adjusted incidence. Despite therapeutic advances, hospitalization and long-term mortality rates remain high, highlighting the need for comprehensive HF strategies in aging societies.

Background: This study aimed to compare the intraoperative stability and early clinical outcomes of 40-mm diameter dual mobility (DM)-total hip arthroplasty (THA) with 36-mm ceramic head (large head) THA in active elderly patients with hip fractures. Methods: A prospective randomized controlled trial was conducted from May 2022 to December 2022. Inclusion criteria were as follows: age ≥ 60 years, displaced femoral neck fracture, Koval grade 1 or 2, planned 54-mm acetabular component, and over 1-year follow-up. Intraoperative stability tests were performed on all patients (internal rotation at 45°, 60°, and 90° of hip fracture). Functional outcomes (Harris Hip Score and University of California, Los Angeles [UCLA] Score) were evaluated at 6 weeks and 3 months postoperatively. Gait analysis using artificial intelligence (AI) techniques was conducted at 3 months postoperatively. Results: The study included 36 DM-THA patients (mean age, 69.6 ± 2.2 years; 44% women) and 37 large head THA patients (mean age, 69.6 ± 1.2 years; 64% women). No statistically significant differences were observed in functional outcomes and hip range of motion between the 2 groups. However, there was a significant difference in the gait speed and stance-swing phase of the large head THA group and the DM-THA group: the DM-THA group demonstrated superior gait speed (2.85 ± 0.83 kph vs. 2.04 ± 1.04 kph, p = 0.003) and higher stance phase ratios (operated side: 63.57% ± 3.82% vs. 48.19% ± 5.50%, p < 0.001; opposite side: 62.77% ± 2.27% vs. 49.93% ± 6.94%, p < 0.001). In the stability test at 90° of hip flexion, the DM-THA group had a measurement of 48.40° ± 5.17°, while the large head THA group had a measurement of 30.94° ± 2.98° (p = 0.012). Despite the lack of statistical significance, the intraoperative stability test showed the dislocation angle was notably different between the groups in the hip flexion position of 60° (51.60° ± 6.09° in the DM-THA group and 40.00° ± 2.80° in the large head THA group, p = 0.072). Conclusions Superior results were observed in the intraoperative stability test and early recovery of gait after DM-THA compared to large head THA. We believe that DM-THA can be a useful surgical option for THA in elderly patients with hip fractures.

Purpose: To compare the clinical outcomes of XEN45 gel stent implantation surgery (ab externo, open conjunctiva) with those of trabeculectomy. Methods: We retrospectively reviewed electronic medical record of 57 patients (62 eyes) treated with XEN implantation surgery (ab externo, open conjunctival approach) between April 1, 2021, and July 31, 2023, by the same surgeon. Preoperative clinical data including intraocular pressure (IOP), the number of glaucoma medications, and visual acuity were collected from 1 day to 12 months postoperatively. These data were compared and analyzed with those of 67 patients (78 eyes) received trabeculectomy between February 1, 2017, and April 30, 2022, by the same surgeon. Statistical analyses were performed with p < 0.05 as significant. Results: Complete surgical success rate was 33.9% and 57.7% of the XEN and trabeculectomy groups, respectively (p = 0.005). The qualified success rate was 79.0% and 93.6%, respectively (p = 0.011). Postoperatively, the XEN group used more glaucoma medications than the trabeculectomy group (1.21 ± 1.05 vs. 0.69 ± 0.90, p = 0.003 at postoperative month 12). After postoperative month 1, the XEN group had a higher IOP (15.77 ± 5.07 mmHg vs. 13.17 ± 3.81 mmHg; at postoperative month 12, p = 0.001) and lower corneal astigmatism than the trabeculectomy group (1.32 ± 0.79 diopters vs. 1.88 ± 1.45 diopters, p = 0.020 at postoperative month 6). There was no significant difference in preoperative and postoperative best-corrected visual acuity (logMAR) between the groups at any of the follow-up period (favorable visual acuity subgroup; logMAR < 0.7). Postoperative complications were 0 cases of XEN group and 13 cases of trabeculectomy group (0% vs. 16.7%, p = 0.001). Also, XEN surgery (24 minutes 40 seconds ± 6 minutes 26 seconds) had a shorter operation time than the trabeculectomy (40 minutes 18 seconds ± 8 minutes 27 seconds, p < 0.001). Conclusions Compared to trabeculectomy, XEN surgery (ab externo, open conjunctiva) showed relatively lower effectiveness (surgical success rate, IOP reduction). However, it demonstrated advantages as a minimally invasive glaucoma surgery, including a surgical success rate approaching about 80%, stability in inducing corneal astigmatism, fewer postoperative complications, and shorter operation times.

The brain’s substantial metabolic requirements, consuming a substantial fraction of the body’s total energy despite its relatively small mass, necessitate sophisticated metabolic mechanisms for efficient energy distribution and utilization.The astrocyte-neuron lactate shuttle (ANLS) hypothesis has emerged as a fundamental framework explaining the metabolic cooperation between astrocytes and neurons, whereby astrocyte-derived lactate serves as a crucial energy substrate for neurons. This review synthesizes current understanding of brain energy metabolism, focusing on the dual roles of lactate as both an energy substrate and a signaling molecule. We examine the molecular underpinnings of metabolic compartmentalization, particularly the differential expression of lactate dehydrogenase (LDH) isozymes between astrocytes and neurons, which facilitates directional lactate flux. Recent evidence has challenged aspects of the classical ANLS model, revealing greater metabolic flexibility in neurons than previously recognized, including substantial LDHA expression and direct glucose utilization capabilities. Our recent studies on LDHB-deficient neurons provide new insights into the compensatory mechanisms and limitations of neuronal lactate metabolism, suggesting a more nuanced understanding of the ANLS hypothesis. Furthermore, we discuss lactate’s emerging role as a signaling molecule in synaptic plasticity, memory formation, and neuroprotection, particularly in ischemic conditions where elevated lactate levels correlate with enhanced neuronal survival through prostaglandin E 2 -mediated vasodilation. This comprehensive review integrates classical perspectives with recent advances, providing an updated framework for understanding brain lactate metabolism and its therapeutic implications in neurological disorders.

Background: This study aimed to compare the intraoperative stability and early clinical outcomes of 40-mm diameter dual mobility (DM)-total hip arthroplasty (THA) with 36-mm ceramic head (large head) THA in active elderly patients with hip fractures. Methods: A prospective randomized controlled trial was conducted from May 2022 to December 2022. Inclusion criteria were as follows: age ≥ 60 years, displaced femoral neck fracture, Koval grade 1 or 2, planned 54-mm acetabular component, and over 1-year follow-up. Intraoperative stability tests were performed on all patients (internal rotation at 45°, 60°, and 90° of hip fracture). Functional outcomes (Harris Hip Score and University of California, Los Angeles [UCLA] Score) were evaluated at 6 weeks and 3 months postoperatively. Gait analysis using artificial intelligence (AI) techniques was conducted at 3 months postoperatively. Results: The study included 36 DM-THA patients (mean age, 69.6 ± 2.2 years; 44% women) and 37 large head THA patients (mean age, 69.6 ± 1.2 years; 64% women). No statistically significant differences were observed in functional outcomes and hip range of motion between the 2 groups. However, there was a significant difference in the gait speed and stance-swing phase of the large head THA group and the DM-THA group: the DM-THA group demonstrated superior gait speed (2.85 ± 0.83 kph vs. 2.04 ± 1.04 kph, p = 0.003) and higher stance phase ratios (operated side: 63.57% ± 3.82% vs. 48.19% ± 5.50%, p < 0.001; opposite side: 62.77% ± 2.27% vs. 49.93% ± 6.94%, p < 0.001). In the stability test at 90° of hip flexion, the DM-THA group had a measurement of 48.40° ± 5.17°, while the large head THA group had a measurement of 30.94° ± 2.98° (p = 0.012). Despite the lack of statistical significance, the intraoperative stability test showed the dislocation angle was notably different between the groups in the hip flexion position of 60° (51.60° ± 6.09° in the DM-THA group and 40.00° ± 2.80° in the large head THA group, p = 0.072). Conclusions Superior results were observed in the intraoperative stability test and early recovery of gait after DM-THA compared to large head THA. We believe that DM-THA can be a useful surgical option for THA in elderly patients with hip fractures.