Flow cytometric lymphocyte subset analysis (FCLSA) is essential for assessing immune status across various diseases and clinical settings. We surveyed current clinical laboratory practices related to FCLSA to establish a baseline reference for future standardization in Korea. Nine university hospitals actively performing FCLSA responded to the 22-question survey, which covered seven categories of laboratory practice. These hospitals used commercial reagent antibody kits from either Beckton Dickinson Biosciences (N = 4) or Beckman Coulter Diagnostics (N = 5). Most hospitals performed daily instrument setup and scheduled maintenance every 2–6 months. Two levels of commercial quality control materials were routinely used each day. Sample and reagent antibody volumes varied across hospitals, even when the same reagent kit was used. Acquired cell counts ranged from 5 × 10 3 to 5 × 10 4 cells, with two hospitals adjusting counts based on the cell type analyzed. Most laboratories reported percentages and general opinions; some additionally reported white blood cell and lymphocyte counts, along with lymphocyte percentages. This is the first comprehensive survey on the clinical laboratory practice of FCLSA in Korea.Standardization of FCLSA should be accelerated to ensure reliable and reproducible results.

Primary breast lymphoma is a rare malignant breast tumor, accounting for <1% of all breast cancers. Among them, diffuse large B-cell lymphoma is the most common histologic subtype.However, primary mucosa-associated lymphoid tissue (MALT) lymphoma is less common and more indolent than diffuse large B-cell lymphoma, and primary MALT lymphoma of the breast is extremely rare. We report a case of bilateral breast cancer in a 62-year-old woman with primary MALT lymphoma in right braest and contralateral invasive breast cancer in left breast. The patient presented with a palpable right breast lump, which appeared as a noncalcified mass on mammography and an indistinct irregular hypoechoic mass with internal vascularity on breast ultrasonography. The mass was pathologically confirmed by excisional biopsy as primary MALT lymphoma. The patient underwent dynamic contrast-enhanced breast MRI, which additionally detected a small suspicious mass in the left breast. This was a clinically and mammographically occult breast cancer diagnosed as invasive ductal carcinoma.

Primary breast lymphoma is a rare malignant breast tumor, accounting for <1% of all breast cancers. Among them, diffuse large B-cell lymphoma is the most common histologic subtype.However, primary mucosa-associated lymphoid tissue (MALT) lymphoma is less common and more indolent than diffuse large B-cell lymphoma, and primary MALT lymphoma of the breast is extremely rare. We report a case of bilateral breast cancer in a 62-year-old woman with primary MALT lymphoma in right braest and contralateral invasive breast cancer in left breast. The patient presented with a palpable right breast lump, which appeared as a noncalcified mass on mammography and an indistinct irregular hypoechoic mass with internal vascularity on breast ultrasonography. The mass was pathologically confirmed by excisional biopsy as primary MALT lymphoma. The patient underwent dynamic contrast-enhanced breast MRI, which additionally detected a small suspicious mass in the left breast. This was a clinically and mammographically occult breast cancer diagnosed as invasive ductal carcinoma.

Primary breast lymphoma is a rare malignant breast tumor, accounting for <1% of all breast cancers. Among them, diffuse large B-cell lymphoma is the most common histologic subtype.However, primary mucosa-associated lymphoid tissue (MALT) lymphoma is less common and more indolent than diffuse large B-cell lymphoma, and primary MALT lymphoma of the breast is extremely rare. We report a case of bilateral breast cancer in a 62-year-old woman with primary MALT lymphoma in right braest and contralateral invasive breast cancer in left breast. The patient presented with a palpable right breast lump, which appeared as a noncalcified mass on mammography and an indistinct irregular hypoechoic mass with internal vascularity on breast ultrasonography. The mass was pathologically confirmed by excisional biopsy as primary MALT lymphoma. The patient underwent dynamic contrast-enhanced breast MRI, which additionally detected a small suspicious mass in the left breast. This was a clinically and mammographically occult breast cancer diagnosed as invasive ductal carcinoma.

Objective: Primary frozen shoulder causes significant pain and progressively restricts shoulder movements. Diagnosis is made clinically based on patient history and physical examination. Management is mainly non-invasive owing to its self-limiting clinical course. However, clinical practice guidelines for frozen shoulder have not yet been developed in Korea. The developed guidelines aim to provide evidence-based recommendations for the diagnosis and treatment of frozen shoulder. Methods: A guideline development committee reviewed the literature from four databases (PubMed, Embase, Cochrane Library, and KMbase). Using the Population, Intervention, Comparator, and Outcome (PICO) framework, the committee formulated two backgrounds and 16 key questions to address common clinical concerns. Recommendations were made using the Grading of Recommendations, Assessment, Development, and Evaluation framework. Results: Diabetes, thyroid disease, and dyslipidemia significantly increase the risk of developing a frozen shoulder. Although frozen shoulder is often self-limiting, some patients may experience long-term functional disabilities. Ultrasound and magnetic resonance imaging should be used as adjunctive tools alongside clinical diagnosis, and rather than as independent diagnostic methods. Noninvasive approaches, such as medications, physical modalities, exercises, electrical stimulation, and manual therapy, may reduce pain and improve shoulder function. Other noninvasive interventions have limited evidence, and their application should be based on clinical judgment. Intra-articular steroid injections are recommended for treatment, and physiotherapy or hydrodilation with steroid injections can also be beneficial. Conclusion These guidelines provide evidence-based recommendations for diagnosing and treating primary frozen shoulder.

Kimura’s disease (KD) is a rare, chronic inflammatory disorder characterized by angiolymphoid hyperplasia, peripheral eosinophilia, and elevated serum immunoglobulin E levels. It primarily affects young Asian males and typically involves the head and neck region, especially near the mandible and postauricular regions. Orbital involvement is unusual and extraocular muscle (EOM) involvement is exceedingly rare, with only a few cases reported in the literature. The present report describes a case of surgically confirmed KD in a 16-yearold male, involving the bilateral EOM, lacrimal gland, and left parotid gland.

Kimura’s disease (KD) is a rare, chronic inflammatory disorder characterized by angiolymphoid hyperplasia, peripheral eosinophilia, and elevated serum immunoglobulin E levels. It primarily affects young Asian males and typically involves the head and neck region, especially near the mandible and postauricular regions. Orbital involvement is unusual and extraocular muscle (EOM) involvement is exceedingly rare, with only a few cases reported in the literature. The present report describes a case of surgically confirmed KD in a 16-yearold male, involving the bilateral EOM, lacrimal gland, and left parotid gland.

Kimura’s disease (KD) is a rare, chronic inflammatory disorder characterized by angiolymphoid hyperplasia, peripheral eosinophilia, and elevated serum immunoglobulin E levels. It primarily affects young Asian males and typically involves the head and neck region, especially near the mandible and postauricular regions. Orbital involvement is unusual and extraocular muscle (EOM) involvement is exceedingly rare, with only a few cases reported in the literature. The present report describes a case of surgically confirmed KD in a 16-yearold male, involving the bilateral EOM, lacrimal gland, and left parotid gland.

Background: Flow cytometric immunophenotyping of hematolymphoid neoplasms (FCIHLN) is essential for diagnosis, classification, and minimal residual disease (MRD) monitoring. FCI-HLN is typically performed using in-house protocols, raising the need for standardization. Therefore, we surveyed the current status of FCI-HLN in Korea to obtain fundamental data for quality improvement and standardization. Methods: Eight university hospitals actively conducting FCI-HLN participated in our survey.We analyzed responses to a questionnaire that included inquiries regarding test items, reagent antibodies (RAs), fluorophores, sample amounts (SAs), reagent antibody amounts (RAAs), acquisition cell number (ACN), isotype control (IC) usage, positiveegative criteria, and reporting. Results: Most hospitals used acute HLN, chronic HLN, plasma cell neoplasm (PCN), and MRD panels. The numbers of RAs were heterogeneous, with a maximum of 32, 26, 12, 14, and 10 antibodies used for acute HLN, chronic HLN, PCN, ALL-MRD, and multiple myeloma-MRD, respectively. The number of fluorophores ranged from 4 to 10. RAs, SAs, RAAs, and ACN were diverse. Most hospitals used a positive criterion of 20%, whereas one used 10% for acute and chronic HLN panels. Five hospitals used ICs for the negative criterion. Positiveegative assignments, percentages, and general opinions were commonly reported. In MRD reporting, the limit of detection and lower limit of quantification were included. Conclusions This is the first comprehensive study on the current status of FCI-HLN in Korea, confirming the high heterogeneity and complexity of FCI-HLN practices. Standardization of FCI-HLN is urgently needed. The findings provide a reference for establishing standard FCI-HLN guidelines.

Objectives: . Using tissue-engineered materials for esophageal reconstruction is a technically challenging task in animals that requires bioreactor training to enhance cellular reactivity. There have been many attempts at esophageal tissue engineering, but the success rate has been limited due to difficulty in initial epithelialization in the special environment of peristalsis. The purpose of this study was to evaluate the potential of an artificial esophagus that can enhance the regeneration of esophageal mucosa and muscle through the optimal combination of a double-layered polymeric scaffold and a custom-designed mesenchymal stem cell-based bioreactor system in a canine model. Methods: . We fabricated a novel double-layered scaffold as a tissue-engineered esophagus using an electrospinning technique. Prior to transplantation, human-derived mesenchymal stem cells were seeded into the lumen of the scaffold, and bioreactor cultivation was performed to enhance cellular reactivity. After 3 days of cultivation using the bioreactor system, tissue-engineered artificial esophagus was transplanted into a partial esophageal defect (5×3 cm-long resection) in a canine model. Results: . Scanning electron microscopy (SEM) showed that the electrospun fibers in a tubular scaffold were randomly and circumferentially located toward the inner and outer surfaces. Complete recovery of the esophageal mucosa was confirmed by endoscopic analysis and SEM. Esophagogastroduodenoscopy and computed tomography also showed that there were no signs of leakage or stricture and that there was a normal lumen with complete epithelialization. Significant regeneration of the mucosal layer was observed by keratin-5 immunostaining. Alpha-smooth muscle actin immunostaining showed significantly greater esophageal muscle regeneration at 12 months than at 6 months. Conclusion . Custom-designed bioreactor cultured electrospun polyurethane scaffolds can be a promising approach for esophageal tissue engineering.