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.

Purpose: There have been efforts to find alternative samples other than standard samples of tissue or plasma for mutational analyses for lung cancer patients. However, no other sample or technique has replaced the mutational analyses using standard samples. In this prospective study, we assessed a novel bronchoscopy method, named as targeted washing technique, for detecting the epidermal growth factor receptor (EGFR) mutation. Materials and Methods: A 3.0-mm ultrathin bronchoscope was precisely navigated to the target lung lesion with the assistance of virtual bronchoscopic navigation and fluoroscopy. Once the bronchoscope is placed in front of target lung lesion, 0.9% normal saline was instilled for targeted washing. EGFR testing using targeted washing fluid (TWF) was compared to standard methods using plasma or tumor tissue. Results: In 41 TWF samples, the T790M mutation was detected in tissue, plasma, and TWF samples at rates of 22.0%, 9.8%, and 29.3%, respectively. The overall EGFR T790M detection rate using tissue, plasma, or TWF samples was 36.6%, with TWF samples increasing the T790M mutation detection rate by up to 10%. The accuracy of T790M mutation detection using TWF sample was 82.9% compared with standard samples. Four patients were found to have the EGFR T790M mutation solely through EGFR testing using TWF, which repeated rebiopsies using either plasma or tissue finally confirmed to have the T790M mutation. Conclusion We demonstrated the clinical potential of targeted washing technique for molecular testing, which can be a good option to overcome spatial heterogeneity, low sensitivity of plasma sample or technical limitations in collecting tumor tissues.

Cervical foraminal lipoma is a rare cause of cervical radiculopathy. We report the case of a 47-year-old woman who presented with a 1-year history of right arm pain and paresthesia that was refractory to conservative treatment. Magnetic resonance imaging demonstrated a well-defined mass within the right C5-6 neural foramen, causing compression of the exiting C6 nerve root. The patient underwent microsurgical excision via posterior cervical laminoforaminotomy. Intraoperatively, a lipomatous mass compressing the nerve root was identified and completely removed. Histopathological examination confirmed a benign lipoma. Postoperatively, the patient experienced marked symptomatic improvement, with no recurrence of symptoms at a 6-month follow-up. Although it is uncommon, cervical foraminal lipoma should be considered in patients with persistent radiculopathy and atypical imaging findings, and surgical excision can provide favorable clinical outcomes.

Background and Objectives: Clinical characteristics and outcomes in acute heart failure (AHF) vary by phenotype. We assessed phenotype-specific features, treatment patterns, and outcomes in a nationwide Korean cohort. Methods: The Korean Heart Failure III registry prospectively enrolled 7,351 AHF admissions at 47 hospitals. Among 6,777 patients with available left ventricular ejection fraction (EF), phenotypes were defined as heart failure with reduced EF (HFrEF, ≤40%), mildly reduced EF (HFmrEF,41–49%), or preserved EF (HFpEF, ≥50%). The primary endpoint was a 12-month composite of all-cause death or heart transplantation, evaluated from index admission and, among hospital survivors, from discharge. We used inverse probability weighting (multinomial generalized boosted models with stabilized, trimmed weights) and weighted Cox proportional-hazards models to estimate hazard ratios (HRs). Results: Phenotype distribution was 58.9% HFrEF, 13.6% HFmrEF, and 27.5% HFpEF. Crude 12-month composite rates from index admission were 13.4% (HFrEF), 12.7% (HFmrEF), and 16.8% (HFpEF). After weighting, from index admission, HFmrEF (HR, 0.892; 95% confidence interval [CI], 0.731–1.088) and HFpEF (HR, 1.101; 95% CI, 0.939–1.291) did not differ from HFrEF; from discharge, HFpEF had modestly higher risk (HR, 1.207; 95% CI, 1.008–1.445) whereas HFmrEF did not (HR, 1.039; 95% CI, 0.844–1.279). Hyponatremia and chronic kidney disease were consistent adverse markers, while angiotensin-converting enzyme inhibitor/ angiotensin II receptor blocker use at discharge was protective. Conclusions Across the EF spectrum, phenotypes showed distinct profiles and risk. Postdischarge risk was modestly higher in HFpEF, supporting phenotype-tailored care and systematic discharge optimization in Korean patients with AHF.

Purpose: Arm wrestling is a common strength competition, particularly among young men, including military personnel.While previous studies have examined humeral shaft fractures from arm wrestling or in soldiers, no research has focused on both. This study evaluates the outcomes of dual plating fixation via the anterolateral approach for arm wrestling-induced fractures in soldiers. Methods: This retrospective study included 18 male patients (mean age, 21.7 years) treated at the Armed Forces Daejeon Hospital (May 2022–December 2023). Data on rank, radial nerve injury, fracture type (AO-OTA classification), and clinical outcomes (union time, radial nerve recovery, DASH score) were analyzed. Results: The cohort included 12 soldiers, two non-commissioned officers, and four officers. Common fracture types were A1 and B1, with four cases of radial nerve palsy. Union occurred at 12.5 weeks, and nerve recovery averaged 15 weeks. No cases of non-union or persistent nerve damage were observed. Conclusion Arm wrestling carries a high risk of humeral fractures in soldiers. Awareness and preventive measures should be emphasized. The dual plating fixation technique via the anterolateral approach is highly effective, demonstrating excellent union and recovery outcomes.

Purpose: Arm wrestling is a common strength competition, particularly among young men, including military personnel.While previous studies have examined humeral shaft fractures from arm wrestling or in soldiers, no research has focused on both. This study evaluates the outcomes of dual plating fixation via the anterolateral approach for arm wrestling-induced fractures in soldiers. Methods: This retrospective study included 18 male patients (mean age, 21.7 years) treated at the Armed Forces Daejeon Hospital (May 2022–December 2023). Data on rank, radial nerve injury, fracture type (AO-OTA classification), and clinical outcomes (union time, radial nerve recovery, DASH score) were analyzed. Results: The cohort included 12 soldiers, two non-commissioned officers, and four officers. Common fracture types were A1 and B1, with four cases of radial nerve palsy. Union occurred at 12.5 weeks, and nerve recovery averaged 15 weeks. No cases of non-union or persistent nerve damage were observed. Conclusion Arm wrestling carries a high risk of humeral fractures in soldiers. Awareness and preventive measures should be emphasized. The dual plating fixation technique via the anterolateral approach is highly effective, demonstrating excellent union and recovery outcomes.

Purpose: Arm wrestling is a common strength competition, particularly among young men, including military personnel.While previous studies have examined humeral shaft fractures from arm wrestling or in soldiers, no research has focused on both. This study evaluates the outcomes of dual plating fixation via the anterolateral approach for arm wrestling-induced fractures in soldiers. Methods: This retrospective study included 18 male patients (mean age, 21.7 years) treated at the Armed Forces Daejeon Hospital (May 2022–December 2023). Data on rank, radial nerve injury, fracture type (AO-OTA classification), and clinical outcomes (union time, radial nerve recovery, DASH score) were analyzed. Results: The cohort included 12 soldiers, two non-commissioned officers, and four officers. Common fracture types were A1 and B1, with four cases of radial nerve palsy. Union occurred at 12.5 weeks, and nerve recovery averaged 15 weeks. No cases of non-union or persistent nerve damage were observed. Conclusion Arm wrestling carries a high risk of humeral fractures in soldiers. Awareness and preventive measures should be emphasized. The dual plating fixation technique via the anterolateral approach is highly effective, demonstrating excellent union and recovery outcomes.

Purpose: Arm wrestling is a common strength competition, particularly among young men, including military personnel.While previous studies have examined humeral shaft fractures from arm wrestling or in soldiers, no research has focused on both. This study evaluates the outcomes of dual plating fixation via the anterolateral approach for arm wrestling-induced fractures in soldiers. Methods: This retrospective study included 18 male patients (mean age, 21.7 years) treated at the Armed Forces Daejeon Hospital (May 2022–December 2023). Data on rank, radial nerve injury, fracture type (AO-OTA classification), and clinical outcomes (union time, radial nerve recovery, DASH score) were analyzed. Results: The cohort included 12 soldiers, two non-commissioned officers, and four officers. Common fracture types were A1 and B1, with four cases of radial nerve palsy. Union occurred at 12.5 weeks, and nerve recovery averaged 15 weeks. No cases of non-union or persistent nerve damage were observed. Conclusion Arm wrestling carries a high risk of humeral fractures in soldiers. Awareness and preventive measures should be emphasized. The dual plating fixation technique via the anterolateral approach is highly effective, demonstrating excellent union and recovery outcomes.

Purpose: Arm wrestling is a common strength competition, particularly among young men, including military personnel.While previous studies have examined humeral shaft fractures from arm wrestling or in soldiers, no research has focused on both. This study evaluates the outcomes of dual plating fixation via the anterolateral approach for arm wrestling-induced fractures in soldiers. Methods: This retrospective study included 18 male patients (mean age, 21.7 years) treated at the Armed Forces Daejeon Hospital (May 2022–December 2023). Data on rank, radial nerve injury, fracture type (AO-OTA classification), and clinical outcomes (union time, radial nerve recovery, DASH score) were analyzed. Results: The cohort included 12 soldiers, two non-commissioned officers, and four officers. Common fracture types were A1 and B1, with four cases of radial nerve palsy. Union occurred at 12.5 weeks, and nerve recovery averaged 15 weeks. No cases of non-union or persistent nerve damage were observed. Conclusion Arm wrestling carries a high risk of humeral fractures in soldiers. Awareness and preventive measures should be emphasized. The dual plating fixation technique via the anterolateral approach is highly effective, demonstrating excellent union and recovery outcomes.

Circulating microRNAs (miRNAs) are potential biomarkers for various kidney diseases. In this study, we aimed to identify a circulating miRNA signature for detecting acute kidney injury (AKI) in scrub typhus. Methods: We prospectively enrolled 40 patients with scrub typhus (20 with AKI, AKI group; 20 without AKI, non-AKI group) and 20 healthy volunteers (the HV group). Thereafter, we performed microarray analysis to assess the serum miRNA profiles of all the participants. Then, to identify miRNAs predictive of scrub typhus-associated AKI, we compared miRNA profiles among these three groups. Results: The proportions of miRNAs, small nucleolar RNAs, and small Cajal body-specific ribonucleoproteins were higher in patients with scrub typhus than in the HVs. Further, relative to the HVs, we identified 120 upregulated and 449 downregulated miRNAs in the non-AKI group and 101 upregulated and 468 downregulated miRNAs in the AKI group. We also identified 11 and 110 upregulated and downregulated miRNAs, respectively, in the AKI group relative to the non-AKI group, and among these miRNAs, we noted 14 miRNAs whose levels were significantly upregulated or downregulated in the AKI group relative to their levels in the HV and non-AKI groups. Biological pathway analysis of these 14 miRNAs indicated their potential involvement in various pathways associated with tumor necrosis factor alpha. Conclusion: We identified miRNAs associated with AKI in patients with scrub typhus that have predictive potential for AKI. Thus, they can be used as surrogate markers for the detection of scrub typhus-associated AKI.