Purpose: Human epidermal growth factor receptor 2 (HER2) is amplified or overexpressed in various malignancies, including breast and gastric cancers, and is associated with poor prognosis. Although HER2-targeted therapies, such as trastuzumab, improve outcomes in HER2-positive tumors, resistance often develops, and HER2-low tumors remain largely untargeted. Trastuzumab deruxtecan (T-DXd; DS-8201a) is a HER2-targeted antibody-drug conjugate with potent activity in HER2-positive and HER2-low tumors. This study evaluates its antitumor mechanisms and efficacy in HER2-positive, HER2-low, and homologous recombination deficiency (HRD)–associated models. Materials and Methods: Effects of T-DXd were assessed in cancer cell lines with diverse HER2 expression and HRD status. In vivo efficacy was evaluated using a xenograft model derived from HER2-low SNU-601 gastric cancer cells. Results: T-DXd reduced HER2 phosphorylation and downstream signaling (AKT, ERK) in HER2-positive cells. It induced DNA damage accumulation, as evidenced by increased γH2AX and p-Chk1 expression, and triggered apoptosis through cleaved poly(ADP-ribose) polymerase and caspase-3 activation, confirmed by annexin V staining. Similar effects were observed in HER2-low cells, with greater sensitivity in HRD cells. In xenografts, T-DXd reduced tumor volume by up to 80% at 4 mg/kg and 10 mg/kg. Histological analyses showed decreased Ki-67 and increased apoptosis. Furthermore, T-DXd induced G2/M cell cycle arrest and nuclear anaplasia, suggesting disruption of chromosomal stability as a potential antitumor mechanism. No significant toxicity, including body weight loss, was observed. Conclusion These findings highlight T-DXd’s effectiveness in HER2-low and HRD tumors, supporting its broader clinical application, including strategies targeting DNA damage repair pathways.

Background: Post-transplantation cyclophosphamide (PTCy) and anti-thymocyte globulin (ATG) are common pro‑ phylactic strategies for graft-versus-host disease (GVHD) after haploidentical hematopoietic stem cell transplantation (haplo-HSCT). Interleukin (IL)-6 is a surrogate marker for cytokine release syndrome (CRS) and acute GVHD.Method The clinical outcomes and complications of haplo-HSCT with PTCy plus ATG versus PTCy monotherapy were compared according to serum IL-6 levels at Chungnam National University Hospital (Daejeon, South Korea) from Jan‑ uary 2019 to February 2023. Results: Forty patients who underwent haplo-HSCT were analyzed. A significant difference in IL-6 levels was observed between the PTCy plus ATG and PTCy alone groups (7.47 ± 10.55 vs. 117.65 ± 127.67; p = 0.003). More patients in the PTCy plus ATG group had a CRS grade of 0 than in the PTCy alone group (p < 0.001). Serum IL-6 levels were associated with grades II–IV acute GVHD (r = 0.547, p < 0.001). The cumulative incidence (CI) of grades II–IV acute GVHD was significantly higher in the PTCy alone group (67.9% vs. 4.8%; p < 0.001). No significant difference in the CI for chronic GVHD was detected between the PTCy plus ATG and PTCy alone groups (72.1% vs. 82.0%; p = 0.730). The CI of 1-year non-relapse mortality was significantly higher in the PTCy alone group than in the PTCy plus ATG group (42.2% vs. 15.9%; p = 0.022). The 1-year overall survival (OS) was significantly better in the PTCy plus ATG group (75.9% vs. 35.3%; p = 0.011). The 1-year GVHD-free, relapse-free survival rate was 29.4% in the PTCy alone group and 54.0% in the PTCy plus ATG group (p = 0.038). Conclusion Serum IL-6 levels were higher in the PTCy alone group than in the PTCy plus ATG group. The addition of ATG before stem cell infusion affected IL-6 levels and reduced the incidences of CRS and grade II–IV acute GVHD in haplo-HSCT patients. This study suggests that PTCy plus ATG as GVHD prophylaxis in haplo-HSCT is beneficial in terms of clinical outcomes and complications of HSCT.

Background: Post-transplantation cyclophosphamide (PTCy) and anti-thymocyte globulin (ATG) are common pro‑ phylactic strategies for graft-versus-host disease (GVHD) after haploidentical hematopoietic stem cell transplantation (haplo-HSCT). Interleukin (IL)-6 is a surrogate marker for cytokine release syndrome (CRS) and acute GVHD.Method The clinical outcomes and complications of haplo-HSCT with PTCy plus ATG versus PTCy monotherapy were compared according to serum IL-6 levels at Chungnam National University Hospital (Daejeon, South Korea) from Jan‑ uary 2019 to February 2023. Results: Forty patients who underwent haplo-HSCT were analyzed. A significant difference in IL-6 levels was observed between the PTCy plus ATG and PTCy alone groups (7.47 ± 10.55 vs. 117.65 ± 127.67; p = 0.003). More patients in the PTCy plus ATG group had a CRS grade of 0 than in the PTCy alone group (p < 0.001). Serum IL-6 levels were associated with grades II–IV acute GVHD (r = 0.547, p < 0.001). The cumulative incidence (CI) of grades II–IV acute GVHD was significantly higher in the PTCy alone group (67.9% vs. 4.8%; p < 0.001). No significant difference in the CI for chronic GVHD was detected between the PTCy plus ATG and PTCy alone groups (72.1% vs. 82.0%; p = 0.730). The CI of 1-year non-relapse mortality was significantly higher in the PTCy alone group than in the PTCy plus ATG group (42.2% vs. 15.9%; p = 0.022). The 1-year overall survival (OS) was significantly better in the PTCy plus ATG group (75.9% vs. 35.3%; p = 0.011). The 1-year GVHD-free, relapse-free survival rate was 29.4% in the PTCy alone group and 54.0% in the PTCy plus ATG group (p = 0.038). Conclusion Serum IL-6 levels were higher in the PTCy alone group than in the PTCy plus ATG group. The addition of ATG before stem cell infusion affected IL-6 levels and reduced the incidences of CRS and grade II–IV acute GVHD in haplo-HSCT patients. This study suggests that PTCy plus ATG as GVHD prophylaxis in haplo-HSCT is beneficial in terms of clinical outcomes and complications of HSCT.

Background: Post-transplantation cyclophosphamide (PTCy) and anti-thymocyte globulin (ATG) are common pro‑ phylactic strategies for graft-versus-host disease (GVHD) after haploidentical hematopoietic stem cell transplantation (haplo-HSCT). Interleukin (IL)-6 is a surrogate marker for cytokine release syndrome (CRS) and acute GVHD.Method The clinical outcomes and complications of haplo-HSCT with PTCy plus ATG versus PTCy monotherapy were compared according to serum IL-6 levels at Chungnam National University Hospital (Daejeon, South Korea) from Jan‑ uary 2019 to February 2023. Results: Forty patients who underwent haplo-HSCT were analyzed. A significant difference in IL-6 levels was observed between the PTCy plus ATG and PTCy alone groups (7.47 ± 10.55 vs. 117.65 ± 127.67; p = 0.003). More patients in the PTCy plus ATG group had a CRS grade of 0 than in the PTCy alone group (p < 0.001). Serum IL-6 levels were associated with grades II–IV acute GVHD (r = 0.547, p < 0.001). The cumulative incidence (CI) of grades II–IV acute GVHD was significantly higher in the PTCy alone group (67.9% vs. 4.8%; p < 0.001). No significant difference in the CI for chronic GVHD was detected between the PTCy plus ATG and PTCy alone groups (72.1% vs. 82.0%; p = 0.730). The CI of 1-year non-relapse mortality was significantly higher in the PTCy alone group than in the PTCy plus ATG group (42.2% vs. 15.9%; p = 0.022). The 1-year overall survival (OS) was significantly better in the PTCy plus ATG group (75.9% vs. 35.3%; p = 0.011). The 1-year GVHD-free, relapse-free survival rate was 29.4% in the PTCy alone group and 54.0% in the PTCy plus ATG group (p = 0.038). Conclusion Serum IL-6 levels were higher in the PTCy alone group than in the PTCy plus ATG group. The addition of ATG before stem cell infusion affected IL-6 levels and reduced the incidences of CRS and grade II–IV acute GVHD in haplo-HSCT patients. This study suggests that PTCy plus ATG as GVHD prophylaxis in haplo-HSCT is beneficial in terms of clinical outcomes and complications of HSCT.

Background: Atherogenic dyslipidemia, which is frequently associated with type 2 diabetes (T2D) and insulin resistance, contributes to the development of vascular complications. Statin therapy is the primary approach to dyslipidemia management in T2D, however, the role of non-statin therapy remains unclear. Ezetimibe reduces cholesterol burden by inhibiting intestinal cholesterol absorption. Fibrates lower triglyceride levels and increase high-density lipoprotein cholesterol (HDL-C) levels via peroxisome proliferator- activated receptor alpha agonism. Therefore, when combined, these drugs effectively lower non-HDL-C levels. Despite this, few clinical trials have specifically targeted non-HDL-C, and the efficacy of triple combination therapies, including statins, ezetimibe, and fibrates, has yet to be determined. Methods: This is a multicenter, prospective, randomized, open-label, active-comparator controlled trial involving 3,958 eligible participants with T2D, cardiovascular risk factors, and elevated non-HDL-C (≥100 mg/dL). Participants, already on moderate-intensity statins, will be randomly assigned to either Ezefeno (ezetimibe/fenofibrate) addition or statin dose-escalation. The primary end point is the development of a composite of major adverse cardiovascular and diabetic microvascular events over 48 months. Conclusion This trial aims to assess whether combining statins, ezetimibe, and fenofibrate is as effective as, or possibly superior to, statin monotherapy intensification in lowering cardiovascular and microvascular disease risk for patients with T2D. This could propose a novel therapeutic approach for managing dyslipidemia in T2D.

Background: With the increasing demand for surgical procedures in dermatology, resident education in surgical dermatology has become important for delivering high-quality treatment.However, it remains unclear if a sufficient number of residency programs with quality standards exist, as there has been little research on this subject in South Korea. Objective: To identify the status of surgical dermatology education among residents and assess dermatologists’ perceptions of the subject. Methods: A 35-question survey was developed and distributed to all resident training hospitals and local clinics listed by the Korean Society of Dermatologic Surgery. Only third- and fourthyear residents were included and board-certified specialists from training hospitals and local clinics responded to the surveys. Results: Survey participants included 88 residents and 120 specialists of whom one-quarter of the residents attended regular monthly educational sessions. Most residents (93%) participated in cosmetic procedures, and many performed laser therapy. However, the opportunity for toxin or filler injection was rare, with only 12% of the residents having experience with filler injections. In response, 49% of residents and 32% of specialists said that more cosmetic training was required, whereas 28% of residents and 50% of specialists said that more training for both cosmetic and conventional surgeries was necessary. Conclusion The survey demonstrated a need for more training programs in surgical dermatology during residency and a perception gap between residents and specialists. Therefore, developing educational residency programs that focus on basic dermatologic surgery principles and their applications in cosmetic procedures is essential.

Inflammatory pseudotumor (IPT) is a rare benign tumor of unknown etiology that can occur in almost any organ system. It has neoplastic features such as local recurrence, invasive growth, and vascular invasion, leading to the possibility of malignant sarcomatous changes. The clinical presentations of colonic IPT may include abdominal pain, anemia, a palpable mass, and intestinal obstruction. A few cases of colonic IPT have been reported, but colonic IPT with pedunculated morphology is very rare. Furthermore, since it can mimic malignant polyps, understanding the endoscopic findings of colonic IPT is important for proper treatment. Herein, we present a case of colonic IPT with pseudosarcomatous changes, presenting as a large polyp, mimicking a malignant polyp in the cecum, along with a literature review.

Objectives: The coronavirus disease 2019 (COVID-19) pandemic has continued since its first detection in the Republic of Korea on January 20, 2020. This study describes the early countermeasures used to minimize the risk of COVID-19 outbreaks during cohort quarantine and compares the epidemiological characteristics of 2 outbreaks in long-term care facilities (LTCFs) in Gwangju Metropolitan City in summer 2020. Methods: An epidemiological investigation was conducted via direct visits. We investigated epidemiological characteristics, including incidence, morbidity, and mortality rates, for all residents and staff members. Demographic characteristics were analyzed using a statistical program. Additionally, the method of managing infection in LTCFs is described. Results: Residents and caregivers had high incidence rates in LTCF-A and LTCF-B, respectively. LTCF-B had a longer quarantine period than LTCF-A. The attack rate was 20.02% in LTCF-A and 27.9% in LTCF- B. The mortality rate was 2.3% (1/43) in LTCF-B, the only facility in which a COVID-19 death occurred. Conclusion Extensive management requires contact minimization, which involves testing all contacts to mitigate further transmission in the early stages of LTCF outbreaks. The findings of this study can help inform and prepare public health authorities for COVID-19 outbreaks, particularly for early control in vulnerable facilities.

BACKGROUND: Decellularized extracellular matrix (dECM) is a non-cellular scaffold with various functions in tissue engineering and regenerative medicine. Elastin is related to tissue elasticity and scarless wound healing, abundantly found in lung and blood vessel tissues. We studied the characteristics of blood vessel-derived dECM (VdECM) and its effect in wound healing. METHODS: VdECM was prepared from porcine blood vessel tissue. Weight percentages of elastin of VdECM and atelocollagen were analyzed. Migratory potential of VdECM was tested by scratch assay. VdECM in hydrogel form was microscopically examined, tested for fibroblast proliferation, and examined for L/D staining. Cytokine array of various growth factors in adipocyte-derived mesenchymal stem cell (ASC) media with VdECM was done. Animal wound model showed the wound healing effect of VdECM hydrogel in comparison to other topical agents. RESULTS: VdECM contained 6.7 times more elastin than atelocollagen per unit weight. Microscopic view of 0.35% VdECM hydrogel showed consistent distribution. Compared to 3% atelocollagen, 0.35% VdECM showed superior results in fibroblast migration. Fluorescent microscopic findings of L/D assay had highest percentage of cell survival in 1% VdECM compared to atelocollagen. Growth factor expression was drastically amplified when VdECM was added to ASC media. In the animal study model, epithelialization rate in the VdECM group was higher than that of control, oxytetracycline, and epidermal growth factor ointments. CONCLUSION VdECM contains a high ratio of elastin to collagen and amplifies expressions of many growth factors. It promotes fibroblast migration, proliferation, and survival, and epithelialization comparable to other topical agents.

Background: Although atherosclerosis is likely to be involved in the development of arterial thrombotic events in patients with essential thrombocythemia (ET), abdominal aortic calcification (AAC) has rarely been investigated. We evaluated the prevalence and clinical relevance of AAC at the time of ET diagnosis. Methods: This retrospective study included patients newly diagnosed with ET who underwent abdominal computed tomography (CT) at the time of diagnosis between January 2002 and December 2021 at Chungnam National University Hospital, Daejeon, Korea. CT images were reviewed and an aortic calcification score was assigned. Results: Of the 94 patients (median age, 62 yr; range, 18‒90 yr), AAC was detected in 62 (66.0%).AAC was most commonly mild (33.0%), followed by moderate (22.7%) and severe (5.3%).Old age [odds ratio (OR), 34.37; 95% confidence interval (CI), 12.32‒95.91; P ＜0.001] was an independent risk factor for AAC. The patients with AAC had a higher WBC count (11.8±4.7 vs. 9.7±2.9×109 /L, P =0.017), higher neutrophil-to-lymphocyte ratio (4.3±2.7 vs. 3.1±1.5, P=0.039), and higher JAK2V617F positivity (81.5% vs. 58.8%, P=0.020) compared to those without AAC. AAC was an independent risk factor for arterial thrombotic vascular events that occurred before or at diagnosis of ET (OR, 4.12; 95% CI, 1.11‒15.85; P=0.034). Conclusion AAC is common in patients with ET and is associated with arterial thrombotic events.