Purpose: Low-dose chest computed tomography (LDCT) is recommended for surveillance 2–3 years after curative resection of non-small cell lung cancer (NSCLC); however, supporting clinical evidence is limited. This study compared LDCT with contrast-enhanced chest computed tomography (CECT) in terms of recurrence detection and overall survival (OS) in patients 2 years after curative resection of NSCLC. Materials and Methods: Among patients who underwent curative resection for NSCLC between January 2011 and December 2017 and survived for 2 years without recurrence, 2,083 patients were included. Comparisons between the LDCT and CECT groups were performed in both the entire cohort and propensity score-matched cohort. The primary outcome was the difference in overall survival. Secondary outcomes included time-to-recurrence, recurrence-free survival, and post-recurrence survival in each group. Results: In the propensity score-matched population, the 5-year OS (96.0% for LDCT, 98.0% for CECT, p=0.097) and recurrence-free survival (RFS) (95.4% for LDCT, 96.0% for CECT, p=0.761) did not differ. The OS and RFS did not differ in subgroup analyses stratified by pathologic stage and histologic type. In the competing risk analysis, the overall 5-year cumulative incidence of recurrence did not differ between the two groups (4.56% for LDCT, 3.93% for CECT, p=0.765). When stratified by pathologic stage and histologic type, there was no significant difference in the cumulative incidence of recurrence. The distribution of recurrence sites did not differ between groups. Conclusion Similar OS and RFS were observed in LDCT and CECT surveillance in patients who achieved a 2-year disease-free status after curative resection for NSCLC.

Purpose: Radical cystectomy (RC) is associated with substantial postoperative morbidity, and unplanned readmission remains common despite advances in perioperative management. However, the association between postoperative readmission due to complications and oncologic outcomes after RC for bladder cancer has not been clearly defined. We evaluated the impact of postoperative readmission on overall survival (OS) and cancer-specific survival (CSS) after RC for bladder cancer. Materials and Methods: We retrospectively analyzed 3,972 patients who underwent RC for bladder cancer in a multicenter cohort. Postoperative readmission was defined as unplanned hospitalization within 90 days postsurgery due to surgery-related complications. Survival outcomes were assessed using the Kaplan-Meier method and compared using the log-rank test. Univariable and multivariable Cox proportional hazards regression analyses were performed to identify independent predictors of OS and CSS. Results: Among the study population, 916 patients (23.1%) experienced postoperative readmission. Baseline and perioperative characteristics were generally comparable between patients with and without readmission. Kaplan-Meier analyses demonstrated significantly worse OS and CSS among patients who experienced postoperative readmission (both log-rank p<0.001). In multivariable analyses adjusting for clinicopathological factors, postoperative readmission remained independently associated with worse OS (hazard ratio [HR], 1.654; 95% confidence interval [CI], 1.464–1.868; p<0.001) and CSS (HR, 1.761; 95% CI, 1.509–2.055; p<0.001). Conclusion Postoperative readmission within 90 days after RC was independently associated with inferior long-term oncologic outcomes. These findings suggest the importance of strategies aimed at preventing postoperative complications and subsequent readmission.

With a rapidly aging population and increasing use of antiresorptive agents, medication-related osteonecrosis of the jaw (MRONJ) represents a growing clinical challenge worldwide. To address the need for tailored clinical guidance, a multidisciplinary task force was convened. Five Korean academic societies—the Korean Society for Bone and Mineral Research, the Korean Association of Oral and Maxillofacial Surgeons, the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons, the Korean Society of Osteoporosis, and the Korean Endocrine Society—collaborated to develop this position statement. The consensus was formulated through comprehensive reviews of literature, combined with three rounds of formal surveys to consolidate expert opinion on controversial topics. This position paper provides evidence-based clinical guidelines for the prevention, diagnosis, and management of MRONJ tailored to the Korean healthcare environment. The diagnostic criteria affirm the standard definition but add a provision for diagnosis based on clinical or radiographic evidence of necrotic bone, even if the traditional 8-week timeframe has not been met. The committee advocates for retaining Stage 0 in the staging system to emphasize early detection and preventive intervention. Key recommendations include prescriptive, drug-specific guidelines for prophylactic drug holidays (e.g., a 2-month pause for oral bisphosphonates; timing surgery 3-4 months after the last denosumab injection) to minimize MRONJ risk from dental procedures. This statement also provides a clear framework for therapeutic drug holidays in established MRONJ, carefully balancing the need for jaw healing against systemic fracture risk. For treatment, this statement advocates for early and active surgical intervention across all MRONJ stages, supported by evidence of superior long-term outcomes compared to conservative management.This position statement offers a unique, evidence-based Korean clinical practice guideline for managing MRONJ. It is intended to standardize care, reduce clinical confusion, and ultimately improve patient outcomes by providing a clear framework for decision-making.

Purpose: Although bladder cancer occurs three to 4 times more frequently in men than in women, the relative number of deaths compared to incidence is higher in women, suggesting that women have a worse prognosis than men. Emerging evidence indicates that the activity of the sex steroid hormone pathway may play a role in bladder cancer development, with demonstrations that both androgens and estrogens have biological effects on bladder cancer in vitro and in vivo. This study investigates the influence of sex and menopausal status on recurrence and cancer-specific death (CSD) in bladder cancer patients undergoing radical cystectomy (RC). Materials and Methods: This retrospective analysis included 3,913 patients from the Korean Bladder Cancer Study Group Database who underwent RC between 2010 and 2019. Patients were categorized based on gender and menopausal status (≤50 years: premenopausal; >50 years: postmenopausal). Pathological factors, neoadjuvant chemotherapy, recurrence, and CSD rates were analyzed using chi-square and Fisher exact tests. Results: Among the 3,913 patients, 400 (10.2%) were female. Premenopausal females exhibited significantly lower recurrence rates (28.6%) compared to postmenopausal females (45.7%). CSD rates were similarly reduced in premenopausal females (12.0% vs. 22.2% in postmenopausal females). No significant sex differences in recurrence or CSD were observed among premenopausal patients. Pathological T stage, nodal status, and lymphovascular invasion were significantly associated with recurrence in males, while nodal status alone was significant in females. Neoadjuvant chemotherapy was significantly more frequently administered to male patients under the age of 50, while no difference was observed in the administration of neoadjuvant chemotherapy among female patients based on menopausal status. Conclusion Hormonal changes associated with menopause significantly influence bladder cancer outcomes in women. Premenopausal hormonal environments seem protective, underscoring the need for further research into hormone-driven mechanisms in bladder cancer.

Purpose: This study aimed to evaluate the prognostic value of a trifecta, defined as negative soft tissue surgical margin (STSM), removal of ≥16 lymph nodes, and absence of major complications (Clavien-Dindo classification grade >III) within 90 days, after radical cystectomy (RC), using a large multicenter cohort. Materials and Methods: We retrospectively analyzed data from 3,972 patients with bladder cancer who underwent RC at 11 tertiary centers in South Korea between 2003 and 2024. Survival outcomes, including overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS), were compared according to trifecta status using Kaplan-Meier and Cox regression analyses. Propensity score matching was performed to adjust for baseline differences. Results: A total of 2,014 eligible patients were included in the final analysis, and the trifecta was achieved in 47.8%. Kaplan-Meier analysis demonstrated significantly improved 5- and 10-year OS (66.7% vs. 62.0%; 62.9% vs. 57.2%; p=0.002), CSS (79.3% vs. 75.4%; 77.8% vs. 73.8%; p=0.008), and RFS (62.7% vs. 57.6%; 60.8% vs. 55.2%; p=0.001) in the trifecta group. In multivariable analysis, trifecta achievement was significantly associated with better OS (HR, 0.813; p=0.008), CSS (HR, 0.787; p=0.017), and RFS (HR, 0.844; p=0.036). Among individual components, negative STSM showed the strongest prognostic effect across all endpoints. Conclusions In this large multicenter study, patients who achieved the RC trifecta exhibited significantly superior survival outcomes compared with those who did not. The trifecta may serve as a practical and standardized metric for assessing surgical quality and performance in RC. Future prospective studies are warranted to validate its prognostic and quality-assurance utility.

With a rapidly aging population and increasing use of antiresorptive agents, medication-related osteonecrosis of the jaw (MRONJ) represents a growing clinical challenge worldwide. To address the need for tailored clinical guidance, a multidisciplinary task force was convened. Five Korean academic societies—the Korean Society for Bone and Mineral Research, the Korean Association of Oral and Maxillofacial Surgeons, the Korean Society of Maxillofacial Plastic and Reconstructive Surgeons, the Korean Osteoporosis Society, and the Korean Endocrine Society—collaborated to develop this position statement. The consensus was formulated through comprehensive reviews of literature, combined with three rounds of formal surveys to consolidate expert opinion on controversial topics. This position paper provides evidence-based clinical guidelines for the prevention, diagnosis, and management of MRONJ tailored to the Korean healthcare environment. The diagnostic criteria affirm the standard definition but add a provision for diagnosis based on clinical or radiographic evidence of necrotic bone, even if the traditional 8-week timeframe has not been met. The committee advocates for retaining stage 0 in the staging system to emphasize early detection and preventive intervention. Key recommendations include prescriptive, drug-specific guidelines for prophylactic drug holidays (e.g., a 2-month pause for oral bisphosphonates; timing surgery 3 to 4 months after the last denosumab injection) to minimize MRONJ risk from dental procedures. This statement also provides a clear framework for therapeutic drug holidays in established MRONJ, carefully balancing the need for jaw healing against systemic fracture risk. For treatment, this statement advocates for early and active surgical intervention across all MRONJ stages, supported by evidence of superior long-term outcomes compared to conservative management. This position statement offers a unique, evidence-based Korean clinical practice guideline for managing MRONJ. It is intended to standardize care, reduce clinical confusion, and ultimately improve patient outcomes by providing a clear framework for decision-making.

Purpose: The Korean Society of Coloproctology has been conducting Colorectal Cancer Awareness Campaign, also known as the Gold Ribbon Campaign, every September since 2007. The 2022 campaign was held through a metaverse platform targeting the younger age group under the slogan of raising awareness of early-onset colorectal cancer (CRC). This study aimed to analyze the impact of the 2022 campaign on a metaverse platform. Methods: Anonymized survey data were collected from participants in the metaverse campaign from September 1 to 15, 2022. The satisfaction score of the participants was evaluated by sex, age group, and previous campaign participation status. Results: During the campaign, 2,770 people visited the metaverse. Among them, 455 people participated in the survey (response rate, 16.4%). Approximately 95% of the participants reported being satisfied with the information provided by the campaign, understood the necessity of undergoing screening for and prevention of early-onset CRC, and were familiar with the structure of the metaverse. The satisfaction score for campaign information tended to decrease as the participants’ age increased. When the participants’ overall level of satisfaction with the metaverse platform was assessed, teenagers scored particularly lower than the other age groups. The satisfaction scores for CRC information provided in the metaverse, as well as the scores for recognizing the seriousness and necessity of screening for early-onset CRC, indicated a high positive tendency (P<0.001). Conclusion Most of the 2022 Gold Ribbon Campaign participants were satisfied with the metaverse platform. Medical society should pay attention to increasing participation in and satisfaction with future public campaigns.

Background: The inflation-deflation (ID) method has long been the standard for intraoperative margin assessment in segmentectomy. However, with advancements in vision technology, the use of near-infrared mapping with indocyanine green (ICG) has become increasingly common. This study was conducted to compare the perioperative outcomes and resection margins achieved using these methods. Methods: This retrospective study included patients who underwent direct segmentectomy for clinical stage I lung cancer between January 2018 and September 2022. We compared perioperative factors, including bronchial and parenchymal resection margins, according to the margin assessment method and the type of segmentectomy performed.Since the ICG approach was adopted in April 2021, we also examined a recent subgroup of patients treated from then onward. Results: A total of 319 segmentectomies were performed. ID and ICG were utilized for 261 (81.8%) and 58 (18.2%) patients, respectively. Following April 2021, 61 patients (51.3%) were treated with ID, while 58 (48.7%) received ICG. We observed no significant difference in resection margins between ID and ICG for bronchial (2.7 cm vs. 2.3 cm, p=0.07) or parenchymal (2.5 cm vs. 2.3 cm, p=0.46) margins. Additionally, the length of hospitalization and the complication rate were comparable between groups. Analysis of the recent subgroup confirmed these findings, showing no significant differences in resection margins (bronchial: 2.6 cm vs. 2.3 cm, p=0.25; parenchymal: 2.4 cm vs. 2.3 cm, p=0.75), length of hospitalization, or complication rate. Conclusion The perioperative outcomes and resection margins achieved using ID and ICG were comparable, suggesting that both methods can safely guide segmentectomy procedures.

Objectives: Limited information is available concerning the epidemiology of stroke and acute myocardial infarction (AMI) in the Republic of Korea. This study aimed to develop a national surveillance system to monitor the incidence of stroke and AMI using national claims data. Methods: We developed and validated identification algorithms for stroke and AMI using claims data. This validation involved a 2-stage stratified sampling method with a review of medical records for sampled cases. The weighted positive predictive value (PPV) and negative predictive value (NPV) were calculated based on the sampling structure and the correspondingsampling rates. Incident cases and the incidence rates of stroke and AMI in the Republic ofKorea were estimated by applying the algorithms and weighted PPV and NPV to the 2018National Health Insurance Service claims data. Results: In total, 2,200 cases (1,086 stroke cases and 1,114 AMI cases) were sampled from the 2018 claims database. The sensitivity and specificity of the algorithms were 94.3% and 88.6% for stroke and 97.9% and 90.1% for AMI, respectively. The estimated number of cases, including recurrent events, was 150,837 for stroke and 40,529 for AMI in 2018. The age- and sex-standardized incidence rate for stroke and AMI was 180.2 and 46.1 cases per 100,000 person-years, respectively, in 2018. Conclusion This study demonstrates the feasibility of developing a national surveillance system based on claims data and identification algorithms for stroke and AMI to monitor their incidence rates.

Background: A precise anatomical understanding of the adductor canal (AC) and its neural components is essential for discerning the action mechanism of the AC block. We therefore aimed to clarify the detailed anatomy of the AC using micro-computed tomography (micro-CT), histological evaluation, and immunofluorescence (IF) assays. Methods: Gross dissections of 39 thighs provided morphometric data relevant to injection landmarks. Serial sectional images of the AC were defined using micro-CT and ultrasonography. The fascial and neural structures of the AC proper were histologically evaluated using Masson’s trichrome and Verhoeff-Van Gieson staining, and double IF staining using choline acetyltransferase (ChAT) and neurofilament 200 antibodies. Results: The posteromedial branch insertion of the nerve to vastus medialis (NVM) into the lateral border of the AC proper was lower (14.5 ± 2.4 cm [mean ± SD] above the base of the patella) than the origin of the proximal AC. The AC consists of a thin subsartorial fascia in the proximal region and a thick aponeurosis-like vastoadductor membrane in the distal region. In the proximal AC, the posteromedial branch of the NVM (pmNVM) consistently contained both sensory and motor fibers, and more ChAT-positive fibers were observed than in the saphenous nerve (27.5 ± 11.2 / 104 vs. 4.2 ± 2.6 / 104 [counts/µm2], P < 0.001). Conclusions Anatomical differences in fascial structures between the proximal and distal AC and a mixed neural component of the neighboring pmNVM have been visualized using micro-CT images, histological evaluation, and IF assays.