Anomalous union of the pancreaticobiliary duct (AUPBD) is a congenital malformation in which the pancreatic and biliary ducts join outside the duodenal wall, forming an elongated common channel. Because sphincter action does not directly affect this junction, reciprocal reflux of pancreatic juice and bile occurs, increasing the risk of biliary tract cancer. AUPBD is frequently associated with choledochal cysts and is a known risk factor for biliary malignancies. We report a case of a 70-year-old woman diagnosed with gallbladder cancer with liver metastases, accompanied by AUPBD without choledochal cysts. She presented with upper abdominal pain, obstructive jaundice, and a large hepatic mass on imaging. Endoscopic retrograde cholangiopancreatography confirmed pancreatobiliary-type AUPBD. Despite biliary drainage, her condition rapidly deteriorated and she died soon after. This case underscores the role of AUPBD in carcinogenesis and the need for early recognition and management.

Objective: To evaluate the impact of adding CT to ultrasound (US) for nodal assessment in patients with papillary thyroid microcarcinoma (PTMC), particularly in those with US-node-negative disease. Materials and Methods: This single-center retrospective study included consecutive patients with PTMC (≤1 cm on US) who underwent both US and CT for PTMC staging between August 2016 and January 2020, and subsequently underwent surgery including neck dissection. The number of patients with clinical N1 and pathological N1 disease was assessed. The diagnostic performance of US, CT, and combined US + CT (positive if either was positive) for macroscopic lymph node metastasis (LNM) (i.e., metastatic tumor foci >2 mm) was evaluated. Cases with discordant nodal staging between US and CT were identified.The diagnostic utility of CT was also assessed in a subgroup of patients with node-negative findings on US. Results: Among 982 patients (mean age ± standard deviation, 47.3 ± 11.5 years; 774 female), pathological analysis confirmed cervical LNM in 377 patients, including macroscopic, microscopic, and size-unknown LNM in 187, 175, and 15 patients, respectively. The addition of CT to US improved sensitivity for detecting macroscopic LNM compared to US alone (68.4% [128/187] vs. 26.7% [50/187]; P < 0.001), while maintaining high specificity despite a significant decrease (90.9% [709/780] vs. 97.2% [758/780]; P < 0.001). Discordant nodal staging between US and CT regarding macroscopic LNM was observed in 149 cases (15.2% [149/982]), with 131 patients (87.9% [131/149]) being upstaged by CT. In patients with node-negative US findings, CT detected US-undetected macroscopic LNM in 78 patients (8.7% [78/895]) and exhibited a sensitivity of 56.9% (78/137) and specificity of 93.5% (709/758) for macroscopic LNM. Conclusion The integration of CT with US improved sensitivity for detecting macroscopic LNM in patients with PTMC, identifying those who would otherwise be inappropriately considered candidates for active surveillance based solely on US findings. This may assist in refining patient management.

Objectives: . Differentiated thyroid cancer (DTC) has a favorable prognosis. However, indeterminate lymph nodes (LNs) are common, making it challenging to distinguish recurrent from persistent DTC. Previous studies have not specifically compared the prognosis between recurrent and persistent DTC. Therefore, we aimed to compare prognosis and oncologic characteristics between these two groups. Methods: . This retrospective cohort study was conducted at a single tertiary care institution and included 265 patients with DTC (recurrent, 109; persistent, 156) who underwent reoperation between November 1, 1999, and August 31, 2018, for structural disease. Patients with distant metastasis at the time of initial diagnosis were excluded. Clinical and oncological characteristics, patterns of LN metastasis, disease-free survival (DFS), and overall survival (OS) were compared between the two groups. For DFS, time zero was defined as the date of the second operation. Results: . Recurrent DTC had a higher incidence of central LN metastasis (P=0.003), infield recurrence (P<0.001), and distant metastasis (P<0.001). In contrast, persistent DTC more frequently exhibited lateral LN metastasis (P=0.003) and outfield recurrence (P<0.001). The most common site of neck LN metastasis was ipsilateral level VI/VII (51.4%) in recurrent DTC and ipsilateral level IV (43.0%) in persistent DTC. Ten-year DFS was significantly lower in recurrent DTC than in persistent DTC (41.0% vs. 67.9%; P<0.001). Recurrent DTC, older age, a higher number of metastatic LNs at the second operation (first reoperation), and R1/R2 resection at the second operation were associated with decreased DFS. OS did not significantly differ between recurrent and persistent DTC (P=0.160). Conclusion . Recurrent DTC is associated with poorer DFS than persistent DTC, although OS does not significantly differ between the two groups.

Objective: To examine the risk of cardiovascular disease (CVD) associated with use of tumor necrosis factor inhibitors (TNFi) in patients with ankylosing spondylitis (AS). Methods: This study used data from the Korean National Health Insurance database. Patients aged ≥18 years who were newly diagnosed with AS between 2010 and 2018 and did not suffer prior CVD were included. The primary outcome was a composite endpoint of myocardial infarction (MI) or stroke. The secondary outcomes were specific endpoints of MI, stroke, or congestive heart failure. TNFi use was evaluated as a time-dependent variable. Cox proportional hazard regression was used to examine the association between TNFi use and risk of incident CVD. Results: Of 19,775 patients (mean age, 36.1 years; 75% male), 5,978 (30.2%) were exposed to TNFi treatment during the study period. During a follow-up of 4.8 (interquartile range, 2.9~7.2) years, 522 events of MI or stroke occurred. TNFi use was associated with a lower risk of MI or stroke than no TNFi use after adjusting for traditional CV risk factors and medications (adjusted hazard ratio [aHR], 0.72; 95% confidence interval [CI], 0.55~0.94). The lower risk of MI or stroke associated with TNFi use was consistently observed across subgroups. Risk of congestive heart failure did not differ between users and non-users of TNFi (aHR, 0.94; 95% CI, 0.75~1.18). Conclusion In a real-world AS cohort, TNFi treatment was associated with a reduced risk of atherosclerotic CVD. However, TNFi use was not associated with risk of congestive heart failure.

Purpose: Radiotherapy (RT) remains a cornerstone of curative treatment for localized and locally advanced prostate cancer. However, dose escalation to improve tumor control is often constrained by the proximity of the rectum, which increases the risk of gastrointestinal (GI) and genitourinary toxicities. Biodegradable rectal spacers inserted between the prostate and rectum have emerged as an effective approach to reduce rectal radiation exposure. This guideline provides evidence-based recommendations on indications, contraindications, procedural standards, and clinical management for biodegradable rectal spacer insertion during prostate cancer RT. Materials and Methods: This guideline was developed by a multidisciplinary expert panel through a systematic review of the literature, analysis of international guidelines (National Comprehensive Cancer Network, European Association of Urology, American Society for Radiation Oncology), and expert consensus among radiation oncologists, radiologists, and urologists with clinical experience in spacer insertion. The strength of each recommendation and the level of evidence were classified according to the modified GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system. Results: Spacer insertion is conditionally recommended (Grade C, Level I) for patients receiving definitive external-beam RT without rectal invasion. It reduces the high-dose rectal irradiation volume (V70–75) by >50%, decreases acute GI toxicity, and helps maintain bowel-related quality of life. However, the benefit for late severe toxicity (grade 2 or higher) remains debated in recent meta-analyses. Contraindications include rectal invasion, anatomical inaccessibility, infection, and material hypersensitivity. Procedures should be performed under local anesthesia in a sterile environment by trained physicians. Short-course antibiotics and simulator-based training, including completion of multiple supervised cases, are advised. Conclusion Biodegradable rectal spacer insertion is clinically validated and effective in reducing acute rectal toxicity. Although pivotal trials demonstrated a favorable procedural safety profile, real-world postmarket data include reports of rare but severe procedural complications. This guideline provides standardized recommendations tailored to Korean clinical practice while remaining consistent with international standards, emphasizing the importance of operator training and careful patient selection.

Objective: To explain process of developing basic veterinary clinical performance guidelines, based on frequently observable clinical manifestations, thereby supporting competencybased veterinary education in Korea. Methods: A structured review of learning outcomes established by Korean Association of Veterinary Medical Colleges (KAVMC) was conducted by a planning committee including veterinary educators, practitioners, and advisory members. Owner-oriented descriptions were used to frame each performance task, and each was mapped to corresponding learning outcomes. These tasks were aligned with learning outcomes recommended by the KAVMC to support the development of communication, clinical reasoning, and performance-related competencies among veterinary students, thereby enhancing day-one clinical readiness. Results: In total, 63 clinical manifestations for a guidebook format that can be used for clinical education were identified and categorized by organ systems that are described in language understandable to animal owners. Conclusions and Relevance: The basic veterinary clinical performance guidelines based on common clinical manifestations would serve as a vital component in veterinary education to reinforce core graduation competencies.

Purpose: Radical cystectomy (RC), which is the standard of care for muscle-invasive and high-grade noninvasive bladder cancer, is accompanied by postoperative renal function deterioration. We aimed to evaluate the effect of serum albumin level on postoperative renal function decline after RC. Materials and Methods: A total of 272 patients with estimated glomerular filtration rate (eGFR) ≥60 mL/minute/1.73 m 2 who underwent RC between October 2003 and December 2020 were included. Acute kidney injury (AKI) was defined according to the KDIGO (Kidney Disease Improving Global Outcomes) criteria, while postoperative chronic kidney disease (CKD) progression was defined as an eGFR <60 mL/minute/1.73 m 2 at ≥3 months after RC. Results: In our cohort, 20 (7.4%) and 99 (36.4%) patients experienced postoperative AKI and CKD progression, respectively, with a median follow-up period of 51.5 months. The median preoperative serum albumin level and eGFR were 4.1 g/dL and 82.0 mL/minute/1.73 m 2 , respectively. Preoperative serum albumin less than the median (4.1 g/dL) was associated with postoperative AKI (odds ratio [OR] 3.76, p=0.027) and CKD progression (OR 2.87, p<0.001) after adjusting for other factors. Conclusions Serum albumin level <4.1 g/dL was associated with short- and long-term renal function decline after RC, suggesting that close monitoring of renal function after RC might be considered in these patients.

Background: Barriers to treatment with intravenous thrombolysis (IVT) for patients with acute ischemic stroke (AIS) in South Korea remain incompletely characterized. We analyze a nationwide prospective cohort to determine patient-level features associated with delayed presentation and non-treatment of potential IVT-eligible patients. Methods: We identified consecutive patients with AIS from 01/2011 to 08/2023 from a multicenter and prospective acute stroke registry in Korea. Patients were defined as IVT candidates if they presented within 4.5 hours from the last known well, had no lab evidence of coagulopathy, and had National Institute of Health Stroke Scale (NIHSS) ≥ 4. Multivariable generalized linear mixed regression models were used to investigate the associations between their characteristics and the IVT candidates or the use of IVT among the candidates. Results: Among 84,103 AIS patients, 41.0% were female, with a mean age of 69 ± 13 years and presentation NIHSS of 4 [interquartile range, 1–8]. Out of these patients, 13,757 (16.4%) were eligible for IVT, of whom 8,179 (59.5%) received IVT. Female sex (adjusted risk ratio [RR], 0.90; 95% confidence interval [CI], 0.86–0.94) and lower years of education (adjusted RR, 0.90; 95% CI, 0.84–0.97 for 0–3 years, compared to ≥ 13 years) were associated with a decreased likelihood of presenting as eligible for IVT after AIS; meanwhile, young age (adjusted RR, 1.12; 95% CI, 1.01–1.24 for ≤ 44 years, compared to 75–84 years) was associated with an increased likelihood of being an IVT candidate. Among those who were eligible for IVT, only age was significantly associated with the use of IVT (adjusted RR, 1.09; 95% CI, 1.03–1.16 for age 65–74 and adjusted RR, 0.83; 95% CI, 0.76–0.90 for ≥ 85 years, respectively). Conclusion Most patients with AIS present outside IVT eligibility in South Korea, and only 60% of eligible patients were ultimately treated. We identified increased age, female sex and lower education as key features on which to focus interventions for improving IVT utilization.

Background: Tinnitus is a multifactorial condition with no universally accepted assessment guidelines. The Korean Tinnitus Study Group previously established consensus statements on the definition, classification, and diagnostic tests for tinnitus. As a continuation of this effort, this study aims to establish expert consensus on tinnitus assessment and treatment outcome evaluation, specifically tailored to the Korean clinical context. Methods: A modified Delphi method involving 26 otology experts from across Korea was used. A two-round Delphi survey was conducted to evaluate statements related to tinnitus assessment before and after treatment. Statements were rated on a scale of 1 to 9 for the level of agreement. Consensus was defined as ≥ 70% agreement (score of 7–9) and ≤ 15% disagreement (score of 1–3). Statistical measures such as content validity ratio and Kendall’s coefficient of concordance (W) were calculated to assess agreement levels. Results: Of the 46 assessment-related statements, 17 (37%) reached consensus, though overall pre-treatment assessments showed weak agreement (Kendall’s W = 0.319). Key areas of agreement included the use of the visual analogue scale, numeric rating scale, and validated questionnaires for pre-treatment evaluation. Five statements, such as the use of computed tomography, magnetic resonance imaging, and angiography for diagnosing pulsatile tinnitus, achieved over 90% agreement. For treatment outcome measurements, 8 of 12 statements (67%) reached a consensus, with moderate agreement (Kendall’s W = 0.513). Validated questionnaires and psychoacoustic tests were recommended for evaluating treatment effects within 12 weeks. While standardized imaging for pulsatile tinnitus and additional clinical tests were strongly recommended, full consensus was not achieved across all imaging modalities. Conclusion This study provides actionable recommendations for tinnitus assessment and treatment evaluation, emphasizing the use of standardized tools and individualized approaches based on patient needs. These findings offer a practical framework to enhance consistency and effectiveness in tinnitus management within Korean clinical settings.