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.

Purpose: This study explored the experiences of physicians and nurses providing end-oflife care in Korean acute care hospitals. It aimed to identify the challenges faced in caring for dying patients and to suggest strategies for improving hospital-based end-of-life care. Methods: A qualitative exploratory design was employed using focus group interviews.Eleven healthcare professionals (five physicians and six nurses) working in tertiary or general hospitals participated in the study between July and August 2018. The interviews were conducted using a semi-structured guide covering seven thematic areas. All sessions were audio-recorded, transcribed verbatim, and analyzed thematically following Braun and Clarke’s framework. Results: Six major themes emerged: (1) communication with patients and families, (2) physical care for dying patients, (3) psychological and spiritual support, (4) hospital environment and system constraints, (5) moral distress and emotional burden on healthcare providers, and (6) suggestions for improvement. The participants described difficulties in open communication, limited resources for comfort care, emotional strain from invasive treatment at the end of life, and the absence of standardized institutional protocols.They emphasized the need for structured communication training, multidisciplinary collaboration, and integration of palliative care principles into acute care practice. Conclusion Physicians and nurses play a pivotal yet emotionally demanding role in providing end-oflife care in acute hospitals. Institutional reforms, including education, protocol development, and supportive environments, are essential to ensuring dignified, patient-centered care and sustain healthcare providers in their professional roles.

Artificial intelligence-based segmentation and quantification is a hot topic in cardiovascular imaging. However, the development of clinically useful artificial intelligence-based models for congenital heart disease is challenging owing to morphologic heterogeneity and limited data for training. Although cardiovascular computed tomography is increasingly used in evaluating patients with congenital heart disease, only a few reports have evaluated artificial intelligence-based segmentation algorithms for congenital heart disease. To be familiarized with this trend, we need to understand state-of-the-art segmentation techniques for cardiovascular digital twins as well as basic concept, current challenges, and potential solutions of artificial intelligence-based methods. Additionally, in this review, our learnings from the literature and our pilot study are summarized, and future directions are suggested.

Objective: Pneumonia can be life-threatening, but it is challenging to diagnose because of the low accuracy of chest Xray (CXR), the diagnostic standard. This study examined predictors of pneumonia on computed tomography (CT) in febrile patients with nondiagnostic CXR. Methods: This was a retrospective case-control study conducted in the emergency department (ED) of a tertiary referral center between November 2019 and October 2020. Among adult febrile patients who underwent CXR and a CT scan, 105 cases with pneumonia on CT and 105 controls without pneumonia on CT were consecutively included. None of the patients had a fever focus or a nondiagnostic CXR at the initial work-up. Results: Multivariate regression analysis revealed the following to be significantly associated with pneumonia on CT: male (odds ratio [OR], 2.06; 95% confidence interval [CI], 1.04-4.07), lower respiratory symptoms (OR, 4.33; 95% CI, 1.93-9.72 for one symptom; OR, 7.64; 95% CI, 3.19-18.31 for two or more symptoms), peripheral oxygen saturation (SpO2) <95% (OR, 2.94; 95% CI, 1.03-8.42), body temperature ≥40.0°C (OR, 5.18; 95% CI, 1.14-23.63), and leukocytosis (OR, 2.26; 95% CI, 1.12-4.55). Blood urea nitrogen (BUN)/creatinine (Cr) ≥20 (OR, 2.14; 95% CI, 1.00-4.57) and absolute neutrophil count <500/mm3 (OR, 8.41; 95% CI, 0.81-87.57) tended to have an association with pneumonia on CT. Conclusion Males, lower respiratory tract symptoms, lower SpO2, higher body temperature, and leukocytosis were independent predictors of a diagnosis of pneumonia on CT with nondiagnostic CXR in febrile patients at the ED. In addition, neutropenia and an increased BUN-to-Cr ratio were important predictors of pneumonia.

Background/Aims: Hepatocellular carcinoma (HCC) exhibits significant sex disparities in incidence, yet its molecular mechanisms remain unclear. We explored the role of telomerase reverse transcriptase (TERT) genetic alterations and hepatitis B virus (HBV) integration, both known major contributors to HCC, in sex-specific risk for HBV-related HCC. Methods: We examined 310 HBV-related HCC tissues to investigate sex-specific TERT promoter (TERT-pro) mutations and HBV integration profiles, stratified by sex and age, and validated with single-cell RNA sequencing (scRNA-seq) data. Results: Tumors predominantly exhibited TERT-pro mutations (26.0% vs. 0%) and HBV-TERT integration (37.0% vs. 3.0%) compared to non-tumorous tissues. While TERT-pro mutations increased with age in both sexes, younger males (≤60 years) showed marked predominance compared to younger females. Males had significantly more HBV integrations at younger ages, while females initially had fewer integrations that gradually increased with age. Younger males' integrations showed significantly greater enrichment in the TERT locus compared to younger females, alongside a preference for promoters, PreS/S regions, and CpG islands. Overall, TERT genetic alterations were significantly sex-differential in younger individuals (75.3% in males vs. 23.1% in females) but not in older individuals (76.9% vs. 83.3%, respectively). These alterations were associated with increased TERT expression. The skewed TERT abnormalities in younger males were further corroborated by independent scRNA-seq data. Conclusions Our findings highlight the critical role of TERT alterations and HBV integration patterns in the male predominance of HCC incidence among younger HBV carriers, offering insights for future exploration to optimize sex-specific patient care and HCC surveillance strategies.

Emerging evidence suggests that systemic inflammation may play a critical role in neurological disorders. Recent studies have shown the connection between inflammatory bowel diseases (IBD) and neurological disorders, revealing a bidirectional relationship through the gut-brain axis.Immunotherapies, such as Treg cells infusion, have been proposed for IBD. However, the role of adaptive immune cells in IBD-induced neuroinflammation remains unclear. In this study, we established an animal model for IBD in mice with severe combined immune-deficient (SCID), an adaptive immune deficiency, to investigate the role of adaptive immune cells in IBD-induced neuroinflammation. Mice were fed 1%, 3%, or 5% dextran sulfate sodium (DSS) for 5 days. We measured body weight, colon length, disease activity index (DAI), and crypt damage. Pro-inflammatory cytokines were measured in the colon, while microglial morphology, neuronal count, and inflammatory cytokines were analyzed in the brain. In the 3% DSS group, colitis symptoms appeared at day 7, with reduced colon length and increased crypt damage showing colitis-like symptoms. By day 21, colon length and crypt damage persisted, while DAI showed recovery. Although colonic inflammation peaked at day 7, no significant increase in inflammatory cytokines or microglial hyperactivation was observed in the brain. By day 21, neuroinflammation was detected, albeit with a slight delay, in the absence of adaptive immune cells. The colitis-induced neuroinflammation model provides insights into the fundamental immune mechanisms of the gut-brain axis and may contribute to developing immune cell therapies for IBD-induced neuroinflammation.

Background/Aims: This study aimed to evaluate the performance of the Model for End-Stage Liver Disease (MELD) 3.0 for predicting mortality and liver-related complications compared with the Child-Pugh classification, albumin-bilirubin (ALBI) grade, the MELD, and the MELD sodium (MELDNa) score. Methods: We evaluated a multicenter retrospective cohort of incorporated patients with cirrhosis between 2013 and 2019. We conducted comparisons of the area under the receiver operating characteristic curve (AUROC) of the MELD3.0 and other models for predicting 3-month mortality. Additionally, we assessed the risk of cirrhosis-related complications according to the MELD3.0 score. Results: A total of 3,314 patients were included. The mean age was 55.9±11.3 years, and 70.2% of the patients were male. Within the initial 3 months, 220 patients (6.6%) died, and the MELD3.0had the best predictive performance among the tested models, with an AUROC of 0.851, outperforming the Child-Pugh classification, ALBI grade, MELD, and MELDNa. A high MELD3.0score was associated with an increased risk of mortality. Compared with that of the group with a MELD3.0 score <10 points, the adjusted hazard ratio of the group with a score of 10–20 pointswas 2.176, and that for the group with a score of ≥20 points was 4.892. Each 1-point increase inthe MELD3.0 score increased the risk of cirrhosis-related complications by 1.033-fold. The risk of hepatorenal syndrome showed the highest increase, with an adjusted hazard ratio of 1.149, followed by hepatic encephalopathy and ascites. Conclusions The MELD3.0 demonstrated robust prognostic performance in predicting mortality in patients with cirrhosis. Moreover, the MELD3.0 score was linked to cirrhosis-related complications, particularly those involving kidney function, such as hepatorenal syndrome and ascites.

Background: and Purpose Anti-agrin antibodies (agrin Abs) have recently been identified in patients with myasthenia gravis (MG), sometimes in conjunction with antibodies (Abs) to the acetylcholine receptor (AChR), muscle-specific tyrosine kinase (MuSK), or low-density lipoprotein receptor-related protein 4. This study aimed to develop an in-house cell-based assay (CBA) for detecting agrin Abs, and to test its application to serum samples collected from individuals diagnosed with MG. Methods: Agrin complementary DNA as cloned into a pCMV6-AC-GFP vector, which was subsequently transfected into human embryonic kidney 293T (HEK293T) cells. Transfected HEK293T cells were incubated with patient serum and antihuman immunoglobulin G Ab conjugated with a red fluorescent dye. Agrin Ab levels were measured using the CBA in 389 serum samples: 340 from patients with MG, 36 from patients with other neuromuscular diseases, and 13 from healthy controls. The presence of agrin Ab was determined based on the fluorescence intensity and colocalization using fluorescence microscopy. Results: The expression levels of agrin mRNA and protein in transfected HEK293T cells were confirmed using the reverse-transcription polymerase chain reaction and Western blotting, respectively. Agrin expression in cells was further confirmed by immunocytochemistry.Two (0.6%) of the 340 patients with MG tested positive for agrin Ab: 1 of 191 AChR-positive patients and 1 of 54 MuSK-positive patients. Conclusions We have developed and validated a novel CBA for detecting agrin Abs. This CBA was successfully applied to detect agrin Abs in serum samples obtained from individuals with MG.

Background: Primary Merkel cell carcinoma of the salivary gland is currently not listed in the World Health Organization classification. However, cases of Merkel cell type neuroendocrine carcinomas of the salivary gland with perinuclear cytokeratin 20 positivity have been intermittently reported. We here investigated the clinicopathologic features of additional cases. Methods: Data of four cases of Merkel cell type small cell neuroendocrine carcinoma of the salivary gland were retrieved. To confirm the tumors’ primary nature, clinical records and pathologic materials were reviewed. Optimal immunohistochemical staining was performed to support the diagnosis. Results: All tumors were located in the parotid gland. Possibilities of metastasis were excluded in all cases through a meticulous clinicopathological review. Tumor histology was consistent with the diagnosis of small cell neuroendocrine carcinoma. Tumors’ immunohistochemical phenotypes were consistent with Merkel cell carcinoma, including Merkel cell polyomavirus large T antigen positivity in two of the four cases. Conclusions Merkel cell carcinomas can originate in salivary glands and are partly associated with Merkel cell polyomavirus infection as in cutaneous Merkel cell carcinomas.