Purpose: The clinical utility of routine repeat computed tomography (CT) in pediatric patients with mild traumatic brain injury (TBI) remains controversial. We aimed to identify factors associated with worsening intracranial injury (ICI) on repeat CT in pediatric patients with mild TBI. Methods: This retrospective study included patients aged 0–18 years with mild TBI (Glasgow Coma Scale score 13–15) who presented to an emergency department in South Korea from January 2017 through December 2023. Patients were included if they underwent an initial CT within 24 hours of injury and a repeat CT within 72 hours. Worsening ICI was defined as an increase in hemorrhage size or the development of new lesions on repeat CT. Clinical characteristics, injury mechanisms, and CT findings were compared between patients with and without the worsening ICI. Multivariable logistic regression was performed to identify independent predictors of worsening ICI on repeat CT. Results: A total of 212 patients were included, of whom 48 (22.6%) showed worsening ICIs on repeat CT (i.e., worsening group). The worsening group showed higher median values of age and length of hospital stay, as well as higher percentages of initial Glasgow Coma Scale of 14, motorcycle/bicycle injury, intensive care unit hospitalization, and abnormalities on initial CT (including skull fracture, epidural hemorrhage, subdural hemorrhage, and pneumocephalus), compared with their counterparts. The regression model showed subdural hemorrhage (odds ratio, 4.99 [95% confidence interval, 2.08–11.96]), epidural hemorrhage (4.04 [1.73–9.44]), and motorcycle/bicycle as the injury mechanism (2.94 [1.14–7.59]) as the predictors. Conclusion In pediatric mild TBI, motorcycle/bicycle accidents and the presence of hemorrhages on initial CT may be associated with worsening ICI on repeat CT. These findings support a risk-stratified approach, in which repeat imaging is selectively considered for high-risk patients to reduce unnecessary radiation exposure.

Background: Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) in children, with a rising incidence of macrolide resistance. Early diagnosis is crucial for reducing the disease burden; however, current diagnostic tools have limitations.We evaluated the diagnostic accuracy of serological assays and their performance based on symptom onset in children with CAP. Methods: From September 2023 to September 2024, we prospectively enrolled children with CAP, classified as M. pneumoniae pneumonia (MPP) or non-MPP, from 16 hospitals in Korea. Serological testing included chemiluminescence immunoassay (CLIA) and ELISA for detecting IgM and IgG, along with particle agglutination (PA) for total antibody measurements. Serological responses were analyzed at different times after symptom onset (0–4, 5–9, and 10–21 days). Results: Among 472 children with CAP (362 MPP, 110 non-MPP), 138 (29.2%) underwent PA testing, and 334 (70.8%) underwent IgM testing. PA at a 1:640 cutoff showed 48.0% sensitivity and 100% specificity. CLIA and ELISA showed comparable sensitivities (69.1% vs. 69.2%) and specificities (76.9% vs. 66.7%) for IgM testing. Seropositivity increased significantly with time since symptom onset (P for trend < 0.001), reaching 97.9% for IgM, 62.5% for IgG, and 94.7% for PA at 10–21 days. Conclusions The time post-symptom onset significantly influenced the diagnostic utility of serological tests for pediatric MPP, which showed limited value during the early stage of illness. These findings emphasize the importance of symptom onset-based interpretation of serological test results and their utility in complementing PCR when optimizing MPP diagnosis in children.

Objective: To evaluate the prognostic impact of radiologic and pathologic features in patients with interstitial lung disease (ILD) other than idiopathic pulmonary fibrosis (IPF), and to identify the factors associated with the development of progressive pulmonary fibrosis (PPF) and survival. Materials and Methods: This study retrospectively enrolled 75 patients diagnosed with ILD other than IPF who underwent surgical lung biopsy between January 2004 and December 2020. Three chest radiologists independently reviewed the CT features and extent of fibrosis on preoperative and follow-up CT scans. Two pathologists reviewed the histopathological features, including the presence of interstitial pneumonia. The time to PPF and overall survival were estimated using the Kaplan-Meier method. The associations of CT and pathological features with PPF and all-cause mortality were examined using standard Cox regression and time-dependent Cox models, respectively. Results: A total of 75 non-IPF ILD patients (mean age ± standard deviations 56.4 ± 13.2 years; range, 40–88 years) were enrolled. The median follow-up duration was 75.3 months (range, 7.8–189.8 months). Traction bronchiectasis on CT (adjusted hazard ratio [HR], 6.40; P = 0.003) and body mass index (adjusted HR per 1-kg/m2 increase, 0.82; P = 0.002) were found to be significantly associated with PPF in multivariable analysis. Radiological progression (adjusted HR, 18.44;P < 0.001), symptomatic progression (adjusted HR, 4.19; P = 0.011), and age (adjusted HR for 1-year increase, 1.12; P < 0.001) were significantly associated with death. Conclusion Traction bronchiectasis on CT was a significant predictor of PPF, while radiologic and symptomatic progression and older age were associated with poorer survival in patients with ILD other than IPF. These findings indicate that careful radiological evaluation and symptom monitoring may help to predict disease progression and outcomes in patients with nonIPF ILD.

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: 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: This study analyzed nationwide trends in lung cancer surgery in South Korea over 14 years, focusing on surgical volume, patient demographics, surgical approaches, and outcomes. Materials and Methods: We performed a retrospective cohort study using nationwide health insurance claims data (124,334 cases) and robotic surgery data (1,740 cases) provided by the manufacturer. Patients who underwent lung cancer surgery between 2010 and 2023 were included. Annual trends were assessed using the annual percentage change (APC), and logistic as well as linear regression models were used to identify predictors of mortality and prolonged hospital stay. Results: The annual surgical volume increased from 4,557 in 2010 to 14,184 in 2023 (APC, 8.86%; p < 0.001). Video-assisted thoracoscopic surgery (VATS) became the predominant approach, rising from 52.9% to 94.8% (APC, 4.11%; p < 0.001). Sub-lobar resections increased, with wedge resections growing from 9.0% to 18.5% (APC, 5.72%; p < 0.001) and segmentectomies from 3.0% to 17.9% (APC, 14.63%; p < 0.001). The proportion of female patients increased from 32.0% to 44.7% (APC, 2.39%; p < 0.001), while patients aged 70-79 years increased from 26.3% to 32.3% (APC, 1.60%; p < 0.001) and those aged ≥ 80 years from 2.0% to 6.2% (APC, 9.63%; p < 0.001). The median hospital stay decreased from 13 to 7 days (APC, –4.34%; p < 0.001), and 30-day mortality declined from 2.45% to 0.76% (APC, –8.32%; p < 0.001). Conclusion Lung cancer surgery in Korea has increased substantially, with a notable shift toward minimally invasive and lung-sparing techniques that have improved outcomes. However, persistent disparities underscore the need for a national surgical registry.

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.

Background and Objectives: Differentiating inverted papilloma (IP) from squamous cell carcinoma arising in IP (IP+SCC) is challenging when computed tomography (CT) demonstrates no bone destruction. This study aimed to identify CT and magnetic resonance imaging (MRI) features that distinguish IP from IP+SCC in cases without bone destruction on CT. Methods: We retrospectively reviewed 30 patients with histologically confirmed sinonasal IP (n=15) or IP+SCC (n=15) who underwent preoperative CT and MRI between 2010 and 2023. Imaging variables assessed included tumor origin, tumor volume, CT enhancement pattern, signal intensity on T2-weighted and contrast-enhanced T1-weighted images, apparent diffusion coefficient (ADC), and the presence or loss of the convoluted cerebriform pattern (CCP). Group differences were analyzed using appropriate statistical tests, with p<0.05 considered statistically significant. Results: There was no statistically significant difference in tumor origin between the IP and IP+SCC groups. Tumor volume and CT enhancement patterns also did not differ significantly between the groups. On MRI, IP+SCC more frequently demonstrated intermediate signal intensity on both T2-weighted and contrast-enhanced T1-weighted images compared with IP (p=0.025 and p=0.029, respectively). Median ADC values were significantly lower in the IP+SCC group than in the IP group (0.99×10-3 vs. 1.20×10-3 mm2/s; p=0.026). Loss of the CCP was more common in the IP+SCC group, although the difference did not reach statistical significance. Conclusion In sinonasal IP without bone destruction on CT, MRI appears to be more informative than CT for distinguishing IP+SCC from IP. Intermediate signal intensity on T2-weighted and contrast-enhanced T1-weighted images, along with lower ADC values, supports malignant transformation, whereas tumor size, CT enhancement, and CCP alone are less reliable discriminators.

Purpose: To develop the 2025 update to the Korean colorectal cancer (CRC) screening guidelines by systematically evaluating recent evidence, integrating domestic data, and addressing changes since the 2015 guideline revision, thereby providing an evidence-based standard for clinicians and policymakers. Methods: A multidisciplinary committee developed the guidelines using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. The process included formulation of three key questions addressing screening efficacy, diagnostic accuracy, and optimal screening age and interval. A systematic review of international guidelines and primary literature was conducted, yielding 327 eligible studies. In addition, a utility-based analysis using a Markov model was performed to determine optimal screening ages and intervals. Results: The evidence synthesis identified high-certainty evidence supporting the use of the fecal immunochemical test (FIT) for reducing CRC mortality and moderate-certainty evidence for colonoscopy. Evidence for computed tomographic colonography (CTC) and stool DNA testing was rated as very low certainty. Based on the evidence review and cost-utility analysis, the committee conditionally recommends CRC screening for asymptomatic, average-risk adults aged 45–74 years using either colonoscopy every 10 years or FIT every 1–2 years. CTC and stool DNA testing were not recommended owing to insufficient evidence. Conclusion The 2025 Korean Guidelines for Colorectal Cancer Screening present updated, evidence-based recommendations tailored to the domestic healthcare context. By conditionally endorsing both colonoscopy and FIT for individuals aged 45–74 years, these guidelines aim to improve population-level screening effectiveness and reduce the burden of CRC in South Korea.

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.