Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.

Background: Recent advancements in large language models (LLMs) have accelerated their integration into clinical domains, including laboratory medicine. The performance of LLMs in answering board-level laboratory medicine questions has not been comprehensively evaluated. Given the importance of diagnostic accuracy in this field, rigorous and objective evaluations of LLM capabilities are essential. Methods: We assessed 12 LLMs from OpenAI, Anthropic, and Google using 320 Korean Residency Examination questions (2021–2024) spanning six laboratory medicine subspecialties. Standardized prompts were provided via their application programming interfaces under deterministic settings (temperature = 0). Questions were administered thrice to assess response reproducibility. Outputs were compared with validated answers and analyzed for accuracy, reasoning quality, and error typology. Results: Google’s Gemini 2.0 Pro achieved the highest accuracy (80.0%), followed by OpenAI’s GPT-4.5 (77.2%) and Anthropic’s Claude 3.7 Sonnet (74.1%). Accuracy decreased as the difficulty of questions increased (78.0% for easy vs. 45.1% for challenging). Subspecialty performance varied. Al models underperformed on questions on transfusion medicine (mean accuracy: 38.8%), primarily because of limitations in domain-specific and regional knowledge representations. Incorrect answers primarily resulted from reasoning errors. Reproducibility exceeded 95% for most models; however, some residual non-determinism appeared even with greedy decoding (temperature = 0). Conclusions LLMs demonstrated substantial potential for integration into laboratory medicine, particularly in clinical chemistry and immunology. Performance inconsistencies (particularly for high-difficulty questions) and knowledge gaps (notably for transfusion medicine) highlight the necessity for further development—potentially including domain-specific fine-tuning and retrieval-augmented generation integration—and robust expert oversight before clinical application.

Purpose: Atherosclerotic plaques in peripheral arterial disease (PAD) include fatty, mixed, and calcified types. Plaque burden is significantly associated with restenosis, reintervention, and amputation-free survival. Rotational and aspirational atherectomy (RAA) may effectively remove such plaques. This study aimed to evaluate long-term outcomes of RAA for infrainguinal PAD. Methods: Patients with infrainguinal lesions underwent revascularization using the Jetstream Atherectomy System (Boston Scientific). This 60-month extension assessed primary patency rate (PPR) and clinically driven target lesion revascularization (CD-TLR). Kaplan-Meier curves were used for survival analysis; P < 0.05 was considered statistically significant. Results: A total of 150 patients (mean age, 70.9 years; male, 86.0%; 65.4% with diabetes) were enrolled. The mean lesion length was 15.8 cm, with 74.0% occlusions and 47.3% severe calcification. Lesions were sclerotic (72.4%), thrombosclerotic (13.4%), thrombotic (9.4%), or in-stent (4.7%). A drug-coated balloon (DCB) was used in 85.5% of cases. PPR at 1, 3, and 5 years was 84.1%, 68.1%, and 58.5%, respectively. CD-TLR rates were 93.0%, 81.5%, and 67.4%, respectively. The benefit of DCB was sustained through 3 years but attenuated thereafter, highlighting the need for extended follow-up in infrainguinal interventions. Conclusion RAA demonstrated durable 5-year patency and safety outcomes. Device type, DCB use, lesion morphology, and calcium grade did not significantly influence long-term results. Lesion complexity remains the primary predictor of clinical outcome. Despite the complexity of infrainguinal lesions, the use of RAA demonstrated sustained patency through 3 years, with lesion complexity (particularly TASC classification) emerging as the most critical predictor of long-term success.

Purpose: The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ). Materials and Methods: A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire. Results: Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ. Conclusion KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.

Purpose: The male predominance in the incidence of gastric cancer (GC) is established; however, sex differences in the prognosis of GC remain controversial. As such, this study analyzed the prognosis of patients with GC based on age and sex. Materials and Methods: Data from 14,739 patients diagnosed with GC at Seoul National University Bundang Hospital between 2003 and 2023 were analyzed. Baseline characteristics, histological types of GC, overall and GC-specific survival rates (age and stage stratification), and associated risk factors were analyzed. Results: Females were significantly younger (p < 0.001) and exhibited more gastric body cancers (p < 0.001) and tumors with diffuse-type or poorly differentiated histology (p < 0.001) than males. Females exhibited an advantage over males in terms of overall survival (p=0.004), but not in GC-specific survival. However, age stratification revealed significant sex differences, that females < 50 years of age exhibited survival disadvantages (p < 0.001); however, this trend was reversed with age, and females > 60 years exhibited survival advantages (p < 0.001) for both overall and GC-specific survival. This may be explained by the lower ratio of diffuse-type GC as females age. Furthermore, in the analysis according to stage, females with stage IV disease exhibited significant survival disadvantages, with significantly younger age and a higher proportion of diffuse-type GC which exhibits aggressive features, resulting in poorer survival than in males. Conclusion Age and stage stratification revealed significant differences in survival between the sexes, which can be helpful for public health strategies.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Objective: This study aimed to identify the factors contributing to post-traumatic growth (PTG) among nurses who experienced patient death during the coronavirus disease-2019 (COVID-19) pandemic and to evaluate the necessity of grief support is required. Methods: An online survey was conducted to assess the experiences of nurses at Ulsan University Hospital who lost patients during the past year of the pandemic. In total, 211 nurses were recruited. We obtained information on the participants’ demographic and clinical characteristics. For symptoms rating, we used the following scales: the Post-traumatic Growth Inventory (PTGI), Stress and Anxiety to Viral Epidemic-9 (SAVE-9), Patient Health Questionnaire (PHQ-9), Pandemic Grief Scale (PGS), and Utrecht Grief Rumination Scale (UGRS), and Grief Support in Healthcare Scale (GSHCS). Pearson’s correlation coefficients, linear regression, and mediation analysis were employed. Results: PTGI scores were significantly correlated with the SAVE-9 (r=0.31, p<0.01), PHQ-9 (r=0.31, p<0.01), PGS (r=0.28, p<0.01), UGRS (r=0.45, p<0.01), and GSHCS scores (r=0.46, p<0.01). The linear regression analysis revealed the factors significantly associated with PTGI scores: SAVE-9 (β=0.16, p=0.014), UGRS (β=0.29, p<0.001), and GSHCS (β=0.34, p<0.001). The mediation analysis revealed that nurses’ stress and anxiety about COVID-19 and grief rumination had a direct impact on PTG, with grief support serving as a significant mediator. Conclusion PTG was promoted by increases in the medical staff’s anxiety and stress related to COVID-19, grief rumination, and grief support. For the medical staff’s experience of bereavement to result in meaningful personal and professional growth, family members, colleagues, and other associates should provide thoughtful support.

Objective: This study aims to investigate may moesin deficiency resulted in neurodevelopmental abnormalities caused by negative impact on synaptic signaling ultimately leading to synaptic structure and plasticity. Methods: Behavioral assessments measured neurodevelopment (surface righting, negative geotaxis, cliff avoidance), anxiety (open field test, elevated plus maze test), and memory (passive avoidance test, Y-maze test) in moesin-knockout mice (KO) compared to wild-type mice (WT). Whole exome sequencing (WES) of brain (KO vs. WT) and analysis of synaptic proteins were performed to determine the disruption of signal pathways downstream of moesin. Risperidone, a therapeutic agent, was utilized to reverse the neurodevelopmental aberrance in moesin KO. Results: Moesin-KO pups exhibited decrease in the surface righting ability on postnatal day 7 (p<0.05) and increase in time spent in the closed arms (p<0.01), showing increased anxiety-like behavior. WES revealed mutations in pathway aberration in neuron projection, actin filament-based processes, and neuronal migration in KO. Decreased cell viability (p<0.001) and expression of soluble NSF adapter protein 25 (SNAP25) (p<0.001) and postsynaptic density protein 95 (PSD95) (p<0.01) was observed in days in vitro 7 neurons. Downregulation of synaptic proteins, and altered phosphorylation levels of Synapsin I, mammalian uncoordinated 18 (MUNC18), extracellular signal-regulated kinase (ERK), and cAMP response element-binding protein (CREB) was observed in KO cortex and hippocampus. Risperidone reversed the memory impairment in the passive avoidance test and the spontaneous alternation percentage in the Y maze test. Risperidone also restored the reduced expression of PSD95 (p<0.01) and the phosphorylation of Synapsin at Ser605 (p<0.05) and Ser549 (p<0.001) in the cortex of moesin-KO. Conclusion Moesin deficiency leads to neurodevelopmental delay and memory decline, which may be caused through altered regulation in synaptic proteins and function.

Objective: This study aimed to identify the factors contributing to post-traumatic growth (PTG) among nurses who experienced patient death during the coronavirus disease-2019 (COVID-19) pandemic and to evaluate the necessity of grief support is required. Methods: An online survey was conducted to assess the experiences of nurses at Ulsan University Hospital who lost patients during the past year of the pandemic. In total, 211 nurses were recruited. We obtained information on the participants’ demographic and clinical characteristics. For symptoms rating, we used the following scales: the Post-traumatic Growth Inventory (PTGI), Stress and Anxiety to Viral Epidemic-9 (SAVE-9), Patient Health Questionnaire (PHQ-9), Pandemic Grief Scale (PGS), and Utrecht Grief Rumination Scale (UGRS), and Grief Support in Healthcare Scale (GSHCS). Pearson’s correlation coefficients, linear regression, and mediation analysis were employed. Results: PTGI scores were significantly correlated with the SAVE-9 (r=0.31, p<0.01), PHQ-9 (r=0.31, p<0.01), PGS (r=0.28, p<0.01), UGRS (r=0.45, p<0.01), and GSHCS scores (r=0.46, p<0.01). The linear regression analysis revealed the factors significantly associated with PTGI scores: SAVE-9 (β=0.16, p=0.014), UGRS (β=0.29, p<0.001), and GSHCS (β=0.34, p<0.001). The mediation analysis revealed that nurses’ stress and anxiety about COVID-19 and grief rumination had a direct impact on PTG, with grief support serving as a significant mediator. Conclusion PTG was promoted by increases in the medical staff’s anxiety and stress related to COVID-19, grief rumination, and grief support. For the medical staff’s experience of bereavement to result in meaningful personal and professional growth, family members, colleagues, and other associates should provide thoughtful support.

Objective: This study aims to investigate may moesin deficiency resulted in neurodevelopmental abnormalities caused by negative impact on synaptic signaling ultimately leading to synaptic structure and plasticity. Methods: Behavioral assessments measured neurodevelopment (surface righting, negative geotaxis, cliff avoidance), anxiety (open field test, elevated plus maze test), and memory (passive avoidance test, Y-maze test) in moesin-knockout mice (KO) compared to wild-type mice (WT). Whole exome sequencing (WES) of brain (KO vs. WT) and analysis of synaptic proteins were performed to determine the disruption of signal pathways downstream of moesin. Risperidone, a therapeutic agent, was utilized to reverse the neurodevelopmental aberrance in moesin KO. Results: Moesin-KO pups exhibited decrease in the surface righting ability on postnatal day 7 (p<0.05) and increase in time spent in the closed arms (p<0.01), showing increased anxiety-like behavior. WES revealed mutations in pathway aberration in neuron projection, actin filament-based processes, and neuronal migration in KO. Decreased cell viability (p<0.001) and expression of soluble NSF adapter protein 25 (SNAP25) (p<0.001) and postsynaptic density protein 95 (PSD95) (p<0.01) was observed in days in vitro 7 neurons. Downregulation of synaptic proteins, and altered phosphorylation levels of Synapsin I, mammalian uncoordinated 18 (MUNC18), extracellular signal-regulated kinase (ERK), and cAMP response element-binding protein (CREB) was observed in KO cortex and hippocampus. Risperidone reversed the memory impairment in the passive avoidance test and the spontaneous alternation percentage in the Y maze test. Risperidone also restored the reduced expression of PSD95 (p<0.01) and the phosphorylation of Synapsin at Ser605 (p<0.05) and Ser549 (p<0.001) in the cortex of moesin-KO. Conclusion Moesin deficiency leads to neurodevelopmental delay and memory decline, which may be caused through altered regulation in synaptic proteins and function.