OBJECTIVES: Kudoa septempunctata has been identified as the causative agent of food poisoning following the consumption of raw farmed Paralichthys olivaceus. However, cohort studies providing robust evidence for an association between K. septempunctata and gastrointestinal symptoms remain limited. This prospective cohort study investigated the association between the consumption of K. septempunctata–infected farmed P. olivaceus and the occurrence of gastrointestinal symptoms. METHODS: Individuals who purchased raw farmed P. olivaceus between 2020 and 2021 were selected as the study population. Study data included 2 rounds of questionnaire surveys administered before and after consumption, 2 muscle specimens obtained from each purchased fish, and human biological specimens collected from individuals who developed gastrointestinal symptoms within 24 hours after consumption. Data were analyzed using the chi-square test and t-test, and the association between consumption of K. septempunctata–infected farmed P. olivaceus and gastrointestinal symptoms was evaluated using relative risk estimates between exposure groups. RESULTS: The relative risk of gastrointestinal symptoms associated with exposure to K. septempunctata–infected P. olivaceus ranged from 71.2 (95% confidence interval [CI], 27.0 to 178.6) to 124.5 (95% CI, 43.5 to 355.0) across the 2 case definitions. A strong and statistically significant association was observed between exposure to K. septempunctata–infected P. olivaceus and the development of acute gastrointestinal symptoms. CONCLUSIONS These findings indicate both an association and a causal relationship between consumption of K. septempunctata–infected farmed P. olivaceus and the onset of gastrointestinal symptoms.

Background and Objectives: The clinical significance of incidental pulmonary nodules detected during thyroid cancer evaluation remains unclear. This study aimed to investigate how such findings affect surgical decisionmaking and whether management differs by physician characteristics. Materials and Methods: A web-based survey was distributed to 722 active members of the Korean Thyroid Association in March 2025. Eligible participants included board-certified endocrinologists, endocrine surgeons, and otolaryngologists actively treating thyroid cancer. The questionnaire included clinical scenarios featuring incidental lung nodules found during thyroid cancer work-up, with respondents asked to choose preferred surgical extent (thyroid lobectomy vs. total thyroidectomy) and management approaches. Results: Out of 72 physicians who completed the survey, half (n=36, 50.0%) of the respondents answered that the presence of incidental lung nodules could influence their decision on thyroidectomy extent. Among those influenced by lung nodules, 86.1% recommended total thyroidectomy in patients with high- or intermediate-risk thyroid cancer, while 11.1% would do so for all thyroid cancer patients.Endocrinologists, compared to surgeons, were more likely to choose total thyroidectomy in patients with preoperative incidental lung nodules (78.3% vs. 36.7%, p=0.001). Conclusion Incidental lung nodules may influence surgical planning in clinicians due to the risk of micrometastasis from thyroid cancer. Endocrinologists tend to favor a more extensive surgical approach compared to surgeons, reflecting greater concern for potential metastatic disease. These findings underscore the need for multidisciplinary consensus guidelines for the management of incidental pulmonary nodules in thyroid cancer patients.

Hepatocellular carcinoma (HCC) is a highly invasive tumor with a strong tendency for metastasis. The most common sites of metastasis are the lungs, followed by lymph nodes, adrenal glands, and bones. However, metastasis of HCC to the small bowel is extremely rare. A 42-yearold female with HCC secondary to chronic hepatitis B and lung metastasis underwent a right hepatic lobectomy, followed by two wedge resections performed via video-assisted thoracic surgery, four sessions of transcatheter arterial chemoembolization, and stereotactic body radiation therapy. She was under regular follow-up for HCC, during which her alpha-fetoprotein level increased to 722.2 IU/ml. Abdominal computed tomography (CT) revealed segmental wall thickening and aneurysmal dilatation of the small bowel loops. An 18 F-fluorodeoxyglucose positron emission tomography/CT scan demonstrated a 3.3-cm hypermetabolic mass-like lesion (standardized uptake value: 11.3) in the small bowel. Surgical resection of the affected small bowel segment was performed. Histopathological examination of the specimen confirmed metastatic HCC, with immunohistochemical positivity for hepatocyte-specific antigen. The patient has remained cancer-free for 60 months post-operatively. Surgical intervention may offer favorable long-term outcomes in patients with small bowel metastasis from HCC.

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.

Gastroesophageal reflux disease (GERD) is a chronic and relapsing gastrointestinal disorder characterized by the reflux of gastric contents into the esophagus, leading to troublesome symptoms and/or complications. Since the publication of the 2020 Seoul Consensus on GERD, significant new evidence has emerged, particularly regarding acid-suppressive therapies and diagnostic approaches. This 2025 focused update aims to refine GERD management strategies by incorporating the latest evidence on acid suppressive therapies and regional considerations in Asian populations. This study builds on the 2020 Seoul Consensus by integrating systematic reviews, meta-analyses, and expert consensuses to offer updated recommendations for the definition and medical treatment of GERD. These guidelines incorporate recent advances in acid-suppressive therapies, particularly potassium-competitive acid blockers, and adopt updated diagnostic frameworks in accordance with the Lyon Consensus 2.0. Key clinical questions were identified and structured using the following format: Population, Intervention, Comparator, Outcome. The resulting recommendations address the initial treatment, long-term maintenance strategies, and role of personalized therapy based on disease severity, such as the grade of reflux esophagitis. Six key statements are presented: updated definition and classification of GERD (Statement 1); initial and long-term treatment strategies tailored to GERD phenotypes, such as non-erosive reflux disease, mild erosive esophagitis, and severe erosive esophagitis (Statements 2-5); and dose optimization strategies for long-term safety (Statement 6). These guidelines aim to support gastroenterologists and general healthcare providers in making individualized evidence-based decisions for GERD management.

Background: Postoperative liver regeneration is essential for maintaining hepatic function. This study evaluated the rate, determinants, and volumetric patterns of early liver regeneration after hemihepatectomy. Methods: A retrospective review was conducted of 50 patients who underwent right or left hemihepatectomy between April 2019 and March 2025. Liver and spleen volumes (SV) were assessed preoperatively, at postoperative day (POD) 1 week, and at POD 3 months. Early liver regeneration rate (LRR) was defined as the percentage increase in remnant liver volume at POD 1 week relative to the preoperative future liver remnant (FLR), and patients were categorized into low (<50%) and high (≥50%) LRR groups. Clinical, biochemical, and volumetric variables were compared, and predictors of regeneration were identified using multivariable analyses. Regeneration patterns were also examined according to whether the FLR/standard liver volume (SLV) ratio was <50% or ≥50%. Results: FLR/SLV was the strongest independent predictor of rapid early liver regeneration (p<0.001). Remnants with FLR/SLV <50% exhibited rapid and sustained regeneration, whereas those with FLR/SLV ≥50% showed slower regrowth that plateaued after reaching approximately 90% of SLV. SV increased at POD 1 week in all patients; however, only the FLR/SLV ≥50% group showed a reduction by POD 3 months, whereas the <50% group maintained elevated volumes. Conclusions FLR/SLV reliably predicts early postoperative liver regeneration. Smaller remnants regenerate more rapidly, whereas persistent splenic enlargement suggests a sustained portal hemodynamic burden. Combined evaluation of FLR/SLV and SV may enhance perioperative risk assessment and surgical planning.

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: Although host body composition, nutritional and systemic inflammatory status have been suggested to have an impact on prognosis in patients with colorectal cancer (CRC), their impact on patients with stage IV CRC remains unclear.This study investigated the prognostic effects of those parameters in patients initially diagnosed with stage IV CRC who underwent surgery. Methods: Patients with stage IV CRC who underwent surgery were selected. Preoperative computed tomography images were evaluated for skeletal muscle index, skeletal muscle density (SMD), visceral fat area (VFA), and subcutaneous fat area (SFA). For nutritional status and systemic inflammation, prognostic nutritional index (PNI), neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) were used. The Cox proportional hazard model was used to evaluate the prognostic significance of progression-free survival (PFS) after adjustment for the other covariates in the model. Results: Data of 134 patients with stage IV CRC who underwent surgery between January 2005 and February 2014 were included. SMD, VFA, SFA, PNI, NLR, LMR, and PLR were associated with PFS in the univariable analysis. In the multivariable analysis, SFA (hazard ratio [HR], 0.612; 95% confidence interval [CI], 0.389–0.961; P = 0.033), and PNI (HR, 0.536; 95% CI, 0.345–0.832; P = 0.005) were identified to be independent prognostic factors for PFS. Conclusion SFA and PNI both demonstrated prognostic significance in patients with stage IV CRC. Accordingly, we believe further studies are warranted to determine whether incorporating these factors can aid in surgical decision-making for stage IV CRC patients.

Purpose: Limited treatment options exist for patients with metastatic castration-resistant prostate cancer (mCRPC) after the failure of taxane-based chemotherapy and novel hormonal therapy. Here, we report the safety and efficacy of ifosfamide and mesna in patients with mCRPC after the failure of taxane-based chemotherapy and novel hormonal therapy (NCT06236789). Materials and Methods: Patients with histologically confirmed prostate cancer who had failed taxane-based chemotherapy and novel hormonal therapy received ifosfamide 2,500 mg/m2 and mesna 1,500 mg/m2 on days 1–3, repeated every 21 days. Safety, objective response rate, disease control rate, reduction in serum prostate-specific antigen (PSA) concentration by >50% (PSA50) or >90% (PSA90), radiographic progression-free survival (rPFS), and overall survival (OS) were analyzed. Results: A total of 47 patients with mCRPC were included in the study. The median number of lines of treatment was 5 (range, 3 to 7). All patients were previously administered docetaxel and novel hormonal therapies including abiraterone (51.1%) and/or enzalutamide (61.7%). Thirty-eight patients (80.9%) were administered cabazitaxel. The objective response and disease control rates were 21.3% and 80.9%, respectively. PSA50 and PSA90 were achieved in 31.9% and 10.6%, respectively. During a median follow-up duration of 54.3 months, rPFS and OS were 5.0 and 9.0 months, respectively. All the patients experienced treatment-related adverse events of any grades; however, no new safety signs were detected. Genomic biomarker analysis revealed that alterations in the TP53 pathway were associated with inferior rPFS and OS. Conclusion Ifosfamide and mesna showed appreciable efficacy and manageable safety profiles in heavily treated patients with mCRPC.

Purpose: Chronic myeloid leukemia (CML) in children, adolescents, and young adults is rare and differs from older adults. This study evaluated the outcomes of allogeneic hematopoietic stem cell transplantation (HSCT) in young Korean CML patients during the tyrosine kinase inhibitor (TKI) era. Materials and Methods: A retrospective analysis of 35 CML patients aged < 40 years who underwent allogeneic HSCT from 2009 to 2019 was conducted using Korean Blood and Marrow Transplantation Registry data. Patients were grouped by age < 20 years at HSCT (group 1, n=15) and 20-40 years at HSCT (group 2, n=20). Survival outcomes including overall survival (OS), relapse-free survival (RFS), and event-free survival (EFS) were analyzed using the Kaplan-Meier method. Results: The median time between diagnosis and HSCT was 8.9 months. All the patients achieved engraftment but platelet recovery was significantly slower in group 1 (p=0.034). Acute and chronic graft-versus-host disease occurred in 54.3% and 34.3%, respectively. Five-year OS, RFS, and EFS rates of total patients were 66.8%, 50.8%, and 47.6%, with better OS was observed in group 1 by multivariable analysis (p=0.048). Disease status at HSCT was a significant predictor of OS (p=0.028), RFS (p=0.003), and EFS (p=0.004). Disease progression occurred in 13 out of 35 patients (37.1%); treatment-related mortality accounted for 63.6% of deaths (7 out of 11). Conclusion When performed at a younger age, allogeneic HSCT result in superior outcome in CML. Achieving remission before HSCT is critical for improved outcomes, highlighting the importance of pretransplant remission via optimal TKI strategies and minimal residual disease monitoring.