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: Psoriasis is a chronic inflammatory skin disorder typified by well-demarcated erythematous plaques with scales. While considered an immune-driven condition, its underlying molecular triggers remain insufficiently defined. Cold-inducible RNA-binding protein (CIRP), a stress-response protein, has recently been recognized as a damage-associated molecular pattern that can stimulate immune responses. Objective: This study aimed to explore the potential association between circulating CIRP levels and the clinical as well as histological characteristics of psoriasis. Methods: Serum CIRP concentrations were analyzed in 67 individuals diagnosed with psoriasis and 20 healthy controls. Relationships between CIRP expression and various clinical and histological indices were also examined. Results: Patients with psoriasis exhibited significantly elevated serum CIRP levels compared to healthy individuals. Although correlations were observed between CIRP and certain clinical and histological indicators, CIRP levels did not significantly differ based on disease severity (Psoriasis Area and Severity Index score), joint involvement, or nail changes. Conclusion Our findings support the notion that CIRP may be involved in the immunopathogenesis of psoriasis and could be considered a prospective target for therapeutic modulation.

Background: Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli is among the most important multidrug-resistant pathogens causing bloodstream infections (BSIs).Cefotaximase (CTX-M) enzymes are the most common and highly diverse ESBL family in E.coli. CTX-M-15 in group CTX-M-1 and CTX-M-14 in group CTX-M-9 are the most extensively disseminated enzymes. Multidrug-resistant E. coli strains complicate empirical therapy and increase healthcare burden globally and in Korea. We investigated the molecular epidemiology, sequence types (STs), and ESBL genotypes of E. coli bloodstream isolates in Korea and identified clinical risk factors for cefotaxime resistance. Methods: We collected all non-duplicated isolates of E. coli and related clinical information from patients with BSIs at eight sentinel hospitals in the Korean Global Antimicrobial Resistance Surveillance System (Kor-GLASS) collection network during 2017–2021. Duplicate isolates were removed to ensure representativeness of the data. Antimicrobial susceptibility was tested using disk diffusion tests, and multilocus sequence typing and betalactamase genotyping were performed. Results: Among 9,232 E. coli blood isolates, resistance rates to cefotaxime and ceftazidime were 36.4% and 11.4%, respectively. Among the clinical factors, age > 65 yrs (adjusted odds ratio [aOR], 1.36), hospital-origin infection (aOR, 2.55), and admission type (intensive care unit [ICU] vs. general ward; aOR, 1.34) were significant cefotaxime resistance risk factors. ST131 was the most prevalent among cefotaxime-resistant E. coli (64.8%, 2,180/3,363), followed by ST1193 (5.3%, N = 177), and ST69 (5.1%, N = 170).ST131, ST648, ST405, and ST410 cefotaxime-resistant E. coli isolates frequently harbored blaCTX-M-15, whereas ST1193 and ST68 showed a high proportion of blaCTX-M-27 carriers, and most ST457 and ST5150 isolates carried blaCTX-M-55. Conclusions Continuous monitoring of ESBL-producing E. coli is required to prevent further dissemination, guide empirical therapy, inform infection control policies, and ensure early detection of multidrug-resistant clones with the potential for widespread transmission.

Background: As nationwide government-led whole-genome sequencing (WGS) projects progress, optimizing the clinical integration of large-scale WGS results is crucial. We explored how the initial analysis from Korea’s First WGS Pilot Study for Rare Diseases was applied in clinical practice, and then we reanalyzed the data comprehensively at Samsung Medical Center (SMC) Seoul, Korea. Methods: A prospective cohort study designed to collect WGS data under a Korean national initiative was conducted from August 2020 to December 2021. We focused on patients with rare diseases recruited from 16 university hospitals. The participants included 5,000 individuals (2,200 probands and 2,800 family members). The initial WGS data and diagnostic reference reports (from 682 probands and 484 family members), generated based on the First Korean WGS Pilot Study for Rare Diseases, were subsequently reanalyzed by SMC. Results: The initial analysis of the First Korean WGS Pilot Study data revealed a diagnostic rate of 17%. Upon receiving these results, the SMC conducted two rounds of reanalysis, increasing the diagnostic rate from 15% in the first analysis, to 18% in the second, and finally to 24% in the third (P = 1.6 × 10 −5 ). Key factors in improving the genetic diagnosis included increased detection of novel (likely) pathogenic variants (P = 1.0 × 10 −4 ), improved diagnostic rates with larger family recruitment (P = 0.004), and refined clinical information for more precise genotype–phenotype correlation analysis (40%). Conclusions Although national WGS projects lay a foundation for rare disease diagnosis, hospital-level reanalysis and multidisciplinary collaborations are crucial for optimizing diagnostic outcomes.

Background: Transthyretin amyloidosis, a protein-misfolding disorder characterized by systemic amyloid deposition, can be classified as wild-type transthyretin amyloidosis (ATTRwt) or hereditary transthyretin amyloidosis (ATTRv), depending on the presence of transthyretin (TTR) gene variants. We examined the genetic distribution of TTR variants in Korean patients diagnosed with ATTRv. Methods: We retrospectively reviewed 801 participants who underwent TTR analysis at Samsung Medical Center from 2012 to 2024. The participants were categorized into two groups: in-house probands or relatives, and externally referred probands or relatives. Results: Pathogenic or likely pathogenic TTR variants were detected in 36 of 165 in-house probands (21.8%), among which D38A was the most frequent variant (50.0%; 18/36), followed by M13dup and E89K (8.3% each). Among referred probands, D38A was predominant (54.5%; 12/22), followed by M13dup (22.7%; 5/22). Cardiac amyloid involvement was the most common manifestation, observed in 97.2% (35/36) of in-house probands with ATTRv, followed by peripheral nervous system (PNS; 94.4%) and autonomic nervous system (ANS; 88.9%) involvement. In contrast, ANS involvement was most prevalent among in-house relatives who underwent organ evaluation (61.5%; 24/39), followed by cardiac (52.1%; 25/48) and PNS (48.7%; 19/39) involvement. Five of the eight in-house relatives harboring M13dup (62.5%) showed organ involvement, primarily in the ANS, supporting the pathogenicity of this variant. Conclusions This study provides the largest single-institution dataset of Korean patients with ATTRv, incorporating systematic organ assessments. The predominance of the unique TTR variants D38A and M13dup delineates a distinct genetic landscape that may facilitate accurate and timely diagnosis of ATTRv in the Korean population.

Vitamin B6 is an essential water-soluble vitamin involved in amino acid metabolism, neurotransmitter synthesis, heme biosynthesis, and one-carbon metabolism. Its active form, pyridoxal-5′-phosphate (PLP), serves as a coenzyme in more than 100 enzymatic reactions and is critical for maintaining metabolic homeostasis, immune regulation, and nervous system function. Epidemiological studies have reported inverse associations between vitamin B6 intake or the circulating PLP concentrations and the risk of cardiovascular disease, certain cancers, and diabetes-related metabolic dysfunction. The proposed mechanisms include the modulation of inflammation, oxidative stress, and homocysteine metabolism. Nevertheless, most available evidence is derived from observational studies conducted in Western or non-Korean populations, limiting generalizability and precluding revisions to current intake recommendations based on the chronic disease outcomes. Relevant epidemiological studies, mechanistic evidence, and recent international and national risk assessment reports were reviewed. Although excessive intake from habitual diets is uncommon, the increasing use of dietary supplements has raised concerns regarding chronic high-dose exposure. Accumulating human evidence suggests that long-term supplementation with high pyridoxine doses may induce sensory peripheral neuropathy, even at lower intake levels than previously assumed. Accordingly, recent international risk assessments, including the 2023 re-evaluation by the European Food Safety Authority, have proposed substantially lower Tolerable Upper Intake Level (UL) using benchmark dose modeling based on human data. In the 2025 Dietary Reference Intakes for Koreans, the UL for adults was set at 50 mg/day, reflecting the updated safety evidence and domestic supplement use patterns, while the recommended intake levels were maintained based on the established metabolic requirements. Further population-specific prospective studies and long-term safety data are needed to refine intake guidance and strengthen evidence-based risk management strategies in Korea.

BACKGROUND/OBJECTIVES: Lutein, a dietary carotenoid, plays a crucial role in protecting eye health as an anti-inflammatory agent and antioxidant. Green leafy vegetables constitute a major source of lutein; however, comparative studies on different consumption methods are limited. Therefore, this study aimed to evaluate the bioavailability of lutein from lutein-rich foods, namely, raw vegetables and raw vegetable juice. SUBJECTS/METHODS: In this study, 18 adults were recruited. They were randomly divided into three groups: commercial lutein supplement (LUT, 20 mg), raw vegetable (RV), and raw vegetable juice (RVJ) groups. Blood was collected at 0-, 4-, 6-, 8-, 12-, 24-, and 30-h intervals after the consumption of each test meal. Participants’ serum lutein levels were analyzed using high-performance liquid chromatography (HPLC). Considering lutein’s wellestablished anti-inflammatory properties, changes in inflammatory status were assessed by measuring serum high-sensitivity C-reactive protein (hs-CRP) levels. Furthermore, urinary metabolomic profiling was conducted using 1 H nuclear magnetic resonance spectroscopy to evaluate metabolic alterations. RESULTS: After consuming each lutein-rich food, participants’ blood lutein levels were analyzed, and the serum concentration peaked at 12 h (0.37 ± 0.13 μg/mL), 24 h (0.61 ± 0.18 μg/mL), and 30 h (0.42 ± 0.16 μg/mL) after RV, LUT, and RVJ consumption, respectively.Additionally, hs-CRP levels decreased following lutein-rich food consumption. Twelve hours after consumption, hs-CRP levels decreased to 0.81 and 0.83 mg/L in the RV and RVJ groups, respectively. Twenty-four hours after consumption, they further decreased to 0.68 and 0.74 mg/L in the LUT and RVJ groups, respectively. Thirty hours after consumption, a reduction to 0.61 mg/L was observed in the RVJ group. Furthermore, after consuming each luteinrich food, N-acetyl glycoprotein levels decreased at 24 h, reflecting metabolic alterations potentially associated with lutein metabolism. CONCLUSION These findings suggest that the short-term consumption of lutein-rich foods, regardless of their type or source, potentially yields health benefits.

Purpose: While MRI-based tumor regression grade (mrTRG) has shown promise in evaluating pathologic response to concurrent chemoradiotherapy (CCRT) in rectal cancer, its ability to predict pathologic complete response remains limited.This study aimed to enhance mrTRG’s diagnostic performance in predicting ypT0–1N0 status, a key factor in considering non-radical management after CCRT for locally advanced rectal cancer (LARC). Methods: This retrospective study included 430 patients with LARC who underwent radical resection following CCRT at a single referral hospital between April 2018 and September 2024. Multivariable logistic regression was used to identify predictive factors associated with achieving ypT0–1N0 status. The diagnostic performances of mrTRG1–2 alone and in combination with other factors were assessed by comparing sensitivity, specificity, positive-predictive value (PPV), negative-predictive value, and area under the curve (AUC). Results: Ninety-three patients (21.6%) achieved ypT0–1N0. In the multivariable analysis, fungating type, cT1–2, and mrTRG1–2 were independent predictors for ypT0–1N0. Integrating mrTRG with gross tumor type yielded the highest AUC of 0.689 among the combined models. For predicting ypT0–1N0, the combination of mrTRG and gross tumor type improved PPV (79.2% vs. 41.5% for mrTRG alone) while also demonstrating enhanced sensitivity compared with ycT0–1N0, the conventional MRI-based predictor (40.9% vs. 22.6%). Conclusion This study demonstrated that combining mrTRG and gross tumor type improved the PPV of mrTRG in predicting ypT0–1N0 after CCRT in LARC. Further studies are warranted to validate the role of gross tumor type in refining predictive systems for selecting candidates for non-radical treatment.

Purpose: Metabolic bariatric surgery (MBS) efficacy and safety is established for older patients, but East Asian data are limited. This study aimed to evaluate the safety and efficacy of MBS by comparing older (≥55 years) and younger (<55 years) East Asian patients with obesity. Methods: This multicenter, retrospective review included 410 patients undergoing MBS from January to December 2019.Patients were stratified into the older group (OG, age ≥55 years; n = 39) and the younger group (YG, age <55 years; n = 371). We compared surgical safety, weight parameters, and comorbidity resolution rates. Results: The OG had lower mean body weight (97.9 ± 16.4 kg vs. 113.2 ± 23.1 kg, P < 0.001) but more comorbidities and lower average ABCD score for type 2 diabetes mellitus (T2DM) remission. Postoperative complication rate (12.8% vs. 7.5%, P = 0.400) and postoperative hospital stay (4.1 ± 1.8 days vs. 4.0 ± 8.9 days, P = 0.773) showed no significant differences.At 12 months, the percentage of total weight loss was significantly lower in the OG (23.7 ± 6.9% vs. 27.8 ± 8.4%, P = 0.014).Remission rates for T2DM (47.6% vs. 80.5%, P < 0.001), hypertension (34.6% vs. 57.5%, P = 0.073), and dyslipidemia (12.5% vs. 44.4%, P = 0.012) were also lower in the OG, yet still demonstrated clinically meaningful metabolic improvement. Conclusion MBS is a safe and effective treatment for older East Asians with obesity, offering substantial comorbidity resolution despite achieving a lower weight loss compared to the younger patients.

Background: and Purpose Temporal dissociation between electrographic and clinical seizure onset in mesial temporal lobe epilepsy (MTLE) implies network heterogeneity. We hypothesized that MTLE consists of distinct electroclinical phenotypes defined by divergent seizure propagation dynamics. Methods: We retrospectively analyzed 167 seizures from 13 patients with drug-resistant MTLE who achieved Engel Class I surgical outcomes. Based on the predominant relationship between scalp electroencephalography (EEG) and clinical onset, patients were classified as EEG-first (n=7) or Clinical-first (n=6). Seizure onset patterns, propagation pathways, and temporal dynamics were assessed using scalp and stereoelectroencephalography (SEEG). Results: The cohort included 83 scalp and 84 SEEG seizures. By definition, onset order differed: in EEG-first seizures, scalp changes preceded clinical signs in 70.5%, whereas the reverse occurred in 65.8% of Clinical-first seizures (p<0.001). EEG-first seizures demonstrated longer SEEG-to-clinical latency (28.8±7.7 s vs. 13.0±7.7 s; p=0.004) and rhythmic theta onset on scalp EEG with focal SEEG low-voltage fast activity or preictal spikes. In contrast, Clinical-first seizures showed heterogeneous scalp patterns (theta, delta–theta, or delta slowing). Propagation tended to differ, with anterior pathways more common in EEG-first (69.6%) and posterior pathways in Clinical-first (26.3%), though with partial overlap (p=0.138). Conclusions MTLE comprises two pathophysiologically distinct phenotypes: EEG-first, reflecting a slowly propagating anterior mesial network, and Clinical-first, involving a rapidly spreading posterior network. This classification offers a mechanistic framework for understanding electroclinical dissociation and may refine presurgical evaluation.