The recent approval of trastuzumab deruxtecan for human epidermal growth factor receptor 2 (HER2)–low and HER2-ultralow breast cancer mandates an adequate assessment of these categories. Methods: Seven breast pathologists from the Breast Pathology Study Group of the Korean Society of Pathologists held an on-site expert consensus meeting. Fifteen sets of virtual whole slide images (WSI) of hematoxylin and eosin stain and HER2 immunohistochemistry were provided. The pathologists were given 60 minutes to submit their diagnosis of HER2 expression into null, ultralow, 1+, 2+, or 3+. Afterwards, in-depth discussion and consensus diagnoses were made by real-time visualization of the WSI. Results: After the consensus meeting, unanimous 100% agreements were seen only in five (33.3%) of the examined cases, which consisted of three 1+ cases and two 2+ cases. Two cases (13.3%) had mild disagreement, with only one pathologist’s disagreement. Of note, eight cases (53.3%) showed significant disagreement, defined by more than two pathologists’ disagreement. All HER2-null cases were reclassified as ultralow after consensus review, suggesting potential widespread underclassification of ultralow cases in clinical practice. Conclusions: Experts had significant discrepancies in interpreting HER2-low/ultralow status. It is important to assess if the distinction between HER2-low and ultralow is strictly required and if HER2-null breast cancer exists in reality.

Subarachnoid hemorrhage (SAH) is a stroke subtype with high mortality and poor functional outcomes. Prompt occlusion of a ruptured aneurysm at an early stage is crucial to prevent rebleeding, which can result in even higher mortality and more severe disabilities. The most critical initial decision in SAH management is the choice of treatment method with surgical clipping or endovascular coiling. We aimed to develop an evidence-based clinical guideline to select the optimal initial treatment in patients with SAH. We developed this guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted across four databases (MEDLINE, Embase, Cochrane, and KoreaMed) to answer two population, intervention, comparison, outcome questions comparing clipping and coiling. The risk of bias was assessed using ROB 2.0 and the Newcastle-Ottawa Scale. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagrams and meta-analyses were generated for functional outcome and mortality. We included six randomized control trials (RCTs) and 58 observational studies. Meta-analysis of RCTs showed that coiling improved functional outcomes compared to clipping (odds ratio [OR], 0.91; 95% confidence interval [CI], 0.86–0.97). No significant mortality difference was observed in RCTs (OR, 1.38; 95% CI, 0.91–2.09), but non-RCTs favored clipping for reduced mortality (OR, 0.77; 95% CI, 0.69–0.86). However, it is difficult to generalize these findings to all clinical situations, as patients with SAH have a highly variable clinical course. Final treatment decision should be tailored to the individual patient’s status, including aneurysm location, morphology, and the expertise available at the treatment center. Such decisions are best made by specialists such as a board-certified physician and should be explained to the patient and their caregivers, along with the rationale for selecting the most appropriate treatment at the given hospital. Korea has many certified endovascular neurosurgeons, cerebrovascular surgeons, and certified cerebrovascular centers. Proper selection of the most suitable treatment method by certified physicians and centers would greatly benefit patient outcomes and healthcare professionals.

The mothership (MS) model, where patients are directly transferred to a thrombectomy-capable center, and the drip-and-ship (DS) model, where thrombolysis is initiated at the nearest primary stroke center before transfer for thrombectomy, are the primary transport modes for patients with stroke. We aimed to establish guidelines for selecting the appropriate transfer strategy based on emergent large vessel occlusion (LVO). We developed this guideline based on evidence from systematic reviews and meta-analyses via a de novo process. A systematic literature review was conducted across four databases (MEDLINE, Embase, Cochrane, and KoreaMed) to answer three Population, Intervention, Comparison, and Outcome questions comparing MS and DS models. The risk of bias was assessed using the Newcastle-Ottawa Scale. Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagrams and meta-analyses were generated for functional outcomes, mortality, and successful recanalization. Twenty-six non-randomized controlled studies showed that the MS model improved good functional outcomes by approximately 14% compared with the DS model (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.00–1.30). Fifteen studies reported that mortality in the MS and DS models showed no significant differences (OR, 0.97; 95% CI, 0.84–1.11). Twenty-four studies revealed no significant difference in successful recanalization between the MS and DS models (OR, 0.87; 95% CI, 0.68–1.10). The MS model should be considered first to improve the functional outcome of patients with LVO. However, if thrombectomy cannot be performed immediately after thrombolysis, or if a thrombectomy-enabled hospital is not nearby, the DS model should be considered by stroke specialists depending on transportation time and regional factors. We suggest a mixed approach with the DS model based on specific circumstances or regions to ensure the optimum treatment of patients with acute ischemic stroke (AIS). Appropriate transport for patients with LVO improves the prognosis of AIS.

Purpose: We evaluated the 3-year clinical outcomes of simultaneous Ahmed valve implantation and vitrectomy in patients with neovascular glaucoma. Methods: We retrospectively reviewed 38 eyes that underwent combined Ahmed valve implantation and vitrectomy. Best-corrected visual acuity, intraocular pressure (IOP), and the number of IOP-lowering medications were assessed preoperatively and up to 36 months postoperatively. Patients were categorized into two groups (anterior chamber and vitreous cavity) based on the site of Ahmed valve tube insertion. Clinical outcomes were compared between the two groups. Surgical success was defined as maintaining IOP between 6 and 21 mmHg, with or without topical IOP-lowering medications. Surgical failure was defined as IOP outside this range despite IOP-lowering therapy, loss of vision to no light perception, or the need for valve replacement or additional Ahmed valve implantation. Results: The overall surgical success rate was 68.4%; rates were 58.8% in the anterior chamber group and 76.2% in the vitreous cavity group. The mean durations of target IOP maintenance were 24.91 ± 3.45 months in the anterior chamber group and 29.00 ± 2.89 months in the vitreous cavity group, with no significant difference between groups (p > 0.05). Changes in visual acuity before and after surgery did not significantly differ between groups. However, at 36 months postoperatively, the vitreous cavity group required significantly more IOP-lowering medications (p = 0.044). The most common complication was encapsulation removal (39.5%), followed by tube obstruction (10.5%). Conclusions Surgical success rates and the duration of target IOP maintenance did not significantly differ between the anterior chamber and vitreous cavity groups. However, patients in the vitreous cavity group required more IOP-lowering medications postoperatively. These findings suggest that the tube insertion site should be considered when planning surgery for neovascular glaucoma.

This consensus report presents the first official position statement of the Korean Academy of Periodontology on peri-implant diseases, issued in response to South Korea’s rapidly aging population and the associated rise in peri-implant disease management. It reviews the prevalence, classification, and definition of peri-implant diseases, emphasizing that these conditions progress more aggressively and unpredictably than periodontal diseases.The report also identifies systemic and local risk indicators, diagnostic criteria, and evidencebased treatment protocols for peri-implant mucositis and peri-implantitis, integrating international standards with Korea-specific clinical data. Clinical recommendations include structured maintenance programs, risk-based recall intervals, and patient education, with the goal of reducing disease recurrence and improving long-term implant success.

Hepatocellular carcinoma (HCC) is the most common and lethal type of primary liver cancer, frequently arising from chronic liver injury and inflammation. Despite treatment advancements, HCC prognosis remains poor, emphasizing the need for effective preventive and therapeutic strategies. This study investigates the hepatoprotective and anti-tumor effects of Hongjam, a steamed freeze-dried silkworm powder, in a diethylnitrosamine (DEN) and thioacetamide (TAA)-induced HCC mouse model. Mice were administered DEN intraperitoneally for 8 weeks, followed by TAA in drinking water for 9 weeks, with Hongjam supplementation (0.01, 0.1, and 1 g/kg) provided daily through food. Hongjam markedly reduced the tumor incidence, the size, and the histological lesions compared to the DEN/TAA group. Serum biochemical analysis revealed reduction in liver damage markers, including alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, and total bilirubin, with a notable decrease in total bilirubin surpassing. Immunohistochemical and Western blot analyses demonstrated that Hongjam downregulated expression of proliferation markers, including Ki67, phosphorylation of protein kinase B, and proliferating cell nuclear antigen, while upregulating the pro-apoptotic protein Bcl-2-associated X protein, indicating its dual role in suppressing proliferation and promoting apoptosis. Furthermore, Hongjam inhibited angiogenesis by suppressing the expression of key markers, including interleukin 6, VEGF, hypoxia-inducible factor-1 subunit alpha, platelet-derived growth factor subunit beta, matrix metalloproteinase-2, and cluster of differentiation 31, thereby disrupting the tumor microenvironment. These findings suggest that Hongjam exerts multifaceted protective effects against HCC by targeting proliferation, apoptosis, and angiogenesis pathways, while also mitigating liver damage. This study highlights the potential of Hongjam as a functional food or a complementary therapeutic agent for HCC prevention and management.

BACKGROUND: The skin, a vital organ protecting against microorganisms and dehydration, undergoes structural decline with aging, leading to visible issues such as wrinkles and sagging. Reduced blood vessels exacerbate vulnerability, hindering optimal cellular function and compromising skin health. Polydioxanone (PDO) biomaterials address aging concerns but produce acidic byproducts, causing inflammation. Inorganic particles and nitric oxide (NO) play crucial roles in inhibiting inflammation and promoting skin regeneration. Stem cell-derived extracellular vesicles (EVs) contribute to intercellular communication, offering the potential to enhance cell functions. The study proposes a method to enhance PDO-based medical devices by incorporating inorganic particles and immobilizing EVs, focusing on facial rejuvenation, anti-inflammatory response, collagen formation, and angiogenesis.METHOD: PDO composites with inorganic particles such as magnesium hydroxide (MH) and zinc oxide (ZO) were prepared and followed by EV immobilization. Comprehensive characterization included biocompatibility, anti-inflammation, collagen formation ability, and angiogenesis ability. RESULTS: Bulk-modified PDO composites demonstrated even dispersion of inorganic particles, pH neutralization, and enhanced biocompatibility. EVs immobilized on the composite surface exhibited spherical morphology. Inflammationrelated gene expressions decreased, emphasizing anti-inflammatory effects. Collagen-related gene and protein expressions increased, showcasing collagen formation ability. In addition, angiogenic capabilities were notably improved, indicating potential for skin rejuvenation. CONCLUSION The study successfully developed and characterized PDO composites with inorganic particles and EVs, demonstrating promising attributes for medical applications. These composites exhibit biocompatibility, anti-inflammatory properties, collagen formation ability, and angiogenic potential, suggesting their utility in skin rejuvenation and tissue engineering. Further research and clinical validation are essential.

Purpose: Cannulation of the major papilla is the most challenging part of endoscopic retrograde cholangiopancreatography (ERCP) for which physician-controlled wire-guided cannulation (PCWGC) and assistant-controlled wire-guided cannulation (ACWGC) are used as the cannulation techniques. PCWGC can reportedly save up to about 30% of the labor cost by reducing the number of assistants. This study aims to compare the safety and efficacy of PCWGC and ACWGC. Materials and Methods: Of the 2151 patients aged >20 years (4193 cases) who underwent ERCP at Yonsei University Medical Center between January 2015 and December 2016, 989 were included in this study. Results: Among efficacy outcomes, cannulation success rate, rate of precut sphincterotomy (PCWGC vs. ACWGC: 21.3% vs.25.9%), bile duct cannulation time (PCWGC vs. ACWGC: median 3.0 minutes vs. 3.6 minutes), and total procedure time (PCWGC vs. ACWGC: median 13.6 minutes vs. 13.1 minutes) were not significantly different. Among safety outcomes, lower rates of postERCP pancreatitis were observed with PCWGC than with ACWGC (PCWGC vs. ACWGC: 5.8% vs. 8.8%, p=0.128). Among other post-ERCP adverse events (bleeding, perforation, and cholangitis), the difference was not significant between the groups. Radiation exposure (total dose area product, PCWGC vs. ACWGC: median 1979.9 µGym2 vs. 2062.0 µGym2 , p=0.194) and ERCP cost excluding labor cost (PCWGC vs. ACWGC: $1576 vs. $1547, p=0.606) were not significantly different. Conclusion Requiring less assistants, PCWGC showed comparable efficacy and safety to ACWGC. PCWGC can be considered as an alternative option, especially in facilities lacking manpower and resources.

Recent clinical outcomes of multi-regimen chemotherapy in patients with cholangiocarcinoma (CCC) have shown benefits in terms of overall survival. However, repeated endoscopic biliary drainage (EBD) and serious adverse events negatively affect prolongation of the survival period.The aim of this study was to investigate the prevalence of massive hemobilia and the outcomes of its management with fully covered self-expandable metal stents (FC-SEMSs) in patients with hilum-involving CCC receiving multi-regimen chemotherapy. The methods and effects of FCSEMS placement were retrospectively investigated following the occurrence of massive hemobilia during EBD. A total of 356 patients with CCC received multi-regimen chemotherapy. Among them, 181 patients had hilar invasion, and seven patients (3.9%) developed massive hemobilia during repeated EBD using removable stents. In all cases, the tumor encased the right hepatic artery. In six patients (85.7%), hemostasis was immediately and completely achieved by inserting one or two FC-SEMSs proximal to the hilar invasion area. Therefore, if the tumor encases the right hepatic artery, massive hemobilia is likely to occur during multi-regimen chemotherapy.Thus, prompt placement of a FC-SEMS would be an effective treatment option for massive hemobilia in patients with hilum-involving CCC.