Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area.Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version.Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Purpose: This study aimed to evaluate and optimize microbial DNA extraction methods from urine, a non-invasive sample source, to enhance DNA quality, purity, and reliability for urinary microbiome research and biomarker discovery in bladder cancer. Materials and Methods: A total of 302 individuals (258 with genitourinary cancers and 44 with benign urologic diseases) participated in this study. Urine samples were collected via sterile catheterization, resulting in 445 vials for microbial analysis. DNA extraction was performed using three protocols: the standard protocol (SP), water dilution protocol (WDP), and chelation-assisted protocol (CAP). DNA quality (concentration, purity, and contamination levels) was assessed using NanoDrop spectrophotometry.Microbial analysis was conducted on 138 samples (108 cancerous and 30 benign) using 16S rRNA sequencing. Prior to sequencing on the Illumina MiSeq platform, Victor 3 fluorometry was used for validation. Results: WDP outperformed other methods, achieving significantly higher 260/280 and 260/230 ratios, indicating superior DNA purity and reduced contamination, while maintaining reliable DNA yields. CAP was excluded due to poor performance across all metrics. Microbial abundance was significantly higher in WDP-extracted samples (p<0.0001), whereas SP demonstrated higher alpha diversity indices (p<0.01), likely due to improved detection of low-abundance taxa. Beta diversity analysis showed no significant compositional differences between SP and WDP (p=1.0), supporting the reliability of WDP for microbiome research. Conclusions WDP is a highly effective and reliable method for microbial DNA extraction from urine, ensuring high-quality and reproducible results. Future research should address sample variability and crystal precipitation to further refine microbiome-based diagnostics and therapeutics.

Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area.Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version.Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area.Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version.Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Background: Bullous pemphigoid (BP) is an autoimmune blistering disease driven by autoantibodies against BP180 and BP230. While type 2 inflammation plays a key role, the precise immune cell alterations and transcriptomic changes remain unclear. Objective: To characterize immune cell composition and transcriptomic changes in BP patients using fluorescence-activated cell sorting (FACS)-based immunophenotyping and RNA sequencing. Methods: A case-control study was conducted on 10 newly diagnosed, treatment-naive BP patients and six healthy controls. Disease activity was assessed using the Bullous Pemphigoid Disease Area Index (BPDAI). Peripheral blood mononuclear cells were isolated for FACS analysis to determine immune cell subsets. RNA sequencing was performed to identify differentially expressed genes (DEGs) and enriched pathways. Statistical analyses included t-tests, Mann-Whitney U tests, and correlation analysis. Results: FACS analysis revealed a reduction in CD4 + T cells, T helper 2 (Th2), and B cells in BP patients (p<0.05), alongside an increase in M2a-like monocytes (p<0.001). RNA sequencing identified 262 DEGs, with secretory leukocyte peptidase inhibitor (SLPI) and transmembrane protein 237 being the most significantly upregulated. Proline-serine-threonine phosphatase interacting protein 2 (PSTPIP2) and SAM domain, SH3 domain, and nuclear localization signals 1 (SAMSN1) positively correlated with BPDAI (p<0.001). Gene ontology analysis highlighted enrichment in inflammatory responses and neutrophil degranulation pathways. Conclusion BP patients show distinct immune dysregulation, including decreased CD4 + T cells, Th2, and B cells, increased M2a-like monocytes, altered gene expression profiles, and correlations between PSTPIP2, SAMSN1 and disease activity. These findings provide insights into pathogenesis and potential therapeutic targets of BP.

Background: A picosecond laser irradiation technique has presented satisfactory cosmetic outcomes for the treatment of various pigmented lesions. We aimed to evaluate the clinical results of a picosecond neodymiumdoped:yttrium aluminum garnet (Nd:YAG) (PSNY) laser for the treatment of various pigmented lesions and to compare them with the results of a conventional Q-switched Nd:YAG laser. Methods: A retrospective review of subjects treated with a PSNY laser was performed. Clinical improvement was assessed by two blinded dermatologists using a 5-point Global Assessment Scale (GAS). Adverse events were also assessed. Results: Forty-eight patients were treated with a dual-wavelength (532-nm and/or 1,064-nm) PSNY laser. Sixteen of the 48 patients (33.3%) experienced more than 50% improvement after the PSNY treatment. Patients with café-au-lait macule showed the greatest improvement, which was fair to good (GAS, 3.80 ± 0.76). Patients with postinflammatory hyperpigmentation received the highest number of treatment sessions (6.60 ± 3.44 times). The duration of follow-up was the longest in patients with Ota’s nevus (22.50 ± 5.44 weeks). There were no serious complications during the treatment period. Conclusion In our case series, it was concluded that a dual-wavelength 532-nm and 1,064-nm PSNY laser was safe and effective for the treatment of pigmented lesions in Korean patients.

Purpose: T1 high grade (T1HG) bladder cancer (BC) is a type of non-muscle invasive BC (NMIBC) that is recognized as an aggressive subtype with a heightened propensity for progression. Current risk stratification methods for NMIBC rely on clinicopathological indicators; however, these approaches do not adequately capture the aggressive nature of T1HG BC. Thus, new, more accurate biomarkers for T1HG risk stratification are needed. Here, we enrolled three different patient cohorts and investigated expression of collagen type VI alpha 1 (COL6A1), a key component of the extracellular matrix, at different stages and grades of BC, with a specific focus on T1HG BC. Materials and Methods: Samples from 298 BC patients were subjected to RNA sequencing and real-time polymerase chain reaction. Results: We found that T1HG BC and muscle invasive BC (MIBC) exhibited comparable expression of COL6A1, which was significantly higher than that by other NMIBC subtypes. In particular, T1HG patients who later progressed to MIBC had considerably higher expression of COL6A1 than Ta, T1 low grade patients, and patients that did not progress, highlighting the aggressive nature and higher risk of progression associated with T1HG BC. Moreover, Cox and Kaplan–Meier survival analyses revealed a significant association between elevated expression of COL6A1 and poor progression-free survival of T1HG BC patients (multivariate Cox hazard ratio, 16.812; 95% confidence interval, 3.283–86.095; p=0.001 and p=0.0002 [log-rank test]). Conclusions These findings suggest that COL6A1 may be a promising biomarker for risk stratification of T1HG BC, offering valuable insight into disease prognosis and guidance of personalized treatment decisions.

Background: In a previous study, rhinoplasty rasp was shown an effective method for removal of button osteoma (BO) of the skull. Objective: In the present study, our experience was presented and surgical outcome using high-speed burr in surgery for BO evaluated. Methods: The register-based surgery reports of patients who underwent local excision of BO (2010∼2023) at a single institution were reviewed. Demographics, photodocumentation, radiologic examinations, pathology reports, data of scar prevention, and surgical outcome in the BO study cohort were analyzed. Results: A total of 20 BO lesions in 18 patients (14 females and four males; mean age of 52.4±14.3 years) who underwent surgery using high-speed burr were assessed. The mean size of BO was 9.3 mm (range, 5∼17 mm).Most of the BOs were located on the forehead (19/20, 95.0%), which was associated with the course of the supratrochlear (n=13) or supraorbital nerve (n=6). Minimal hematoma was complicated in three patients (16.7%).Delayed complications, recurrence, and severe scarring during the mean follow-up of 3.1±3.5 months were not reported. Conclusion The use of high-speed burr for surface smoothening may provide good surgical results in minimally invasive BO surgery.

Purpose: Oxaliplatin, a component of the capecitabine plus oxaliplatin (XELOX) regimen, has a more favorable toxicity profile than cisplatin in patients with advanced gastric cancer (GC). However, oxaliplatin can induce sensory neuropathy and cumulative, dose-related toxicities. Thus, the capecitabine maintenance regimen may achieve the maximum treatment effect while reducing the cumulative neurotoxicity of oxaliplatin. This study aimed to compare the survival of patients with advanced GC between capecitabine maintenance and observation after 1st line XELOX chemotherapy. Materials and Methods: Sixty-three patients treated with six cycles of XELOX for advanced GC in six hospitals of the Catholic University of Korea were randomized 1:1 to receive capecitabine maintenance or observation. The primary endpoint was progression-free survival (PFS), analyzed using a two-sided log-rank test stratified at a 5% significance level. Results: Between 2015 and 2020, 32 and 31 patients were randomized into the maintenance and observation groups, respectively. After randomization, the median number of capecitabine maintenance cycles was 6. The PFS was significantly higher in the maintenance group than the observation group (6.3 vs. 4.1 months, P=0.010). Overall survival was not significantly different between the 2 groups (18.2 vs. 16.5 months, P=0.624). Toxicities, such as hand-foot syndrome, were reported in some maintenance group patients. Maintenance treatment was a significant factor associated with PFS in multivariate analysis (hazard ratio, 0.472; 95% confidence interval, 0.250–0.890; P=0.020). Conclusions After 6 cycles of XELOX chemotherapy, capecitabine maintenance significantly prolonged PFS compared with observation, and toxicity was manageable. Maintenance treatment was a significant prognostic factor associated with PFS.

Background: The nuclear factor erythroid 2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2/Keap1) signaling pathway is involved in the regulation of cellular responses to oxidative stress. Nrf2 acts as a cell protector from inflammation, cellular damage, and tumorigenesis, whereas Keap1 is a negative regulator of Nrf2. Dysregulation of the Nrf2/ Keap1 pathway results in tumorigenesis and the active metabolism of tumor cells, leading to high resistance to radiotherapy. This study aimed to evaluate the predictive role of Nrf2 and Keap1 in the radiosensitivity and prognosis of locally advanced rectal cancer (LARC). Methods: In total, 90 patients with LARC underwent surgery after preoperative chemoradiotherapy (CRT). Endoscopic biopsies from the tumors were obtained before radiation, and the Nrf2 and Keap1 expressions were assessed by immunohistochemistry. The response to therapy was evaluated after surgery following CRT according to the pathologic tumor regression grade. The disease-free survival (DFS) and overall survival rates were also documented. The association between the Nrf2 and Keap1 immunoreactivity and the clinicopathological parameters was analyzed. Results: The overexpression of the nuclear Nrf2 before CRT showed a significant correlation with better DFS. The cytoplasmic Nrf2 expression was associated with more residual tumors after radiotherapy and a more unfavorable DFS, indicating lower radiosensitivity. Conclusion CRT is an important issue in LARC and is a major aspect of treatment. Thus, the Nrf2/Keap1 expression may be a potential predictor of preoperative therapeutic resistance.The Nrf2-Keap1 modulators that interact with each other may also be effectively applicable to CRT effect in LARC.