Purpose: Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research. Materials and Methods: Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes.Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes. Results: Data from 5,460 ESD cases from 5,250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days. Conclusions This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.

Objective: This study aimed to evaluate the feasibility, safety, and oncologic outcomes of irreversible electroporation (IRE) using a clustered electrode in patients with locally advanced pancreatic cancer (LAPC). Materials and Methods: In this single-center prospective cohort study, 13 patients with LAPC (median age, 60 years; range, 48–78 years) underwent clustered electrode IRE between September 2022 and September 2024. Patient characteristics, procedural details, and clinical outcomes were recorded. Endpoints included technical success, procedure-related complications, overall survival (OS), and progression-free survival (PFS). Results: Tumors were located in the pancreatic head in four patients (30.8%) and in the body/tail in nine (69.2%). The median tumor size was 2.4 cm (1.5–4.0 cm), and vascular invasion was present in all patients. Technical success was achieved in all patients. Intraoperative IRE was performed in 11 (84.6%) patients, and 2 (15.4%) patients underwent percutaneous IRE. Gastrointestinal bleeding events as major complications occurred in two patients (15.4%) and, both were successfully controlled by embolization. No 60-day mortality was observed. At a median follow-up of 24.5 months (range, 9.9–33.4 months) after IRE, median OS and PFS from IRE were 20.1 and 14.5 months, respectively. Conclusion IRE using clustered electrodes for LAPC appears to be a feasible therapeutic approach, offering reliable technical success and acceptable safety. Survival outcomes are encouraging; however, larger, controlled studies are required.

Objective: To evaluate the feasibility of cerebral computed tomography angiography (CTA) obtained with reduced iodine and low radiation at 70 kVp and the effect of deep learning-based augmented contrast enhancement (DL-ACE) and denoising (DL-DN) algorithms on the CTA quality. Materials and Methods: In this prospective study, 47 healthy volunteers (male:female, 31:16; mean age ± standard deviation, 57.8 ± 10.9 years) were randomly assigned to one of three CTA protocols: Group A (n = 16; 100 kVp, 40 mL of 350 mgI/mL), Group B (n = 16; 70 kVp, 40 mL of 270 mgI/mL), and Group C (n = 15; 70 kVp, 28 mL of 270 mgI/mL [ultralow iodine]), with an injection rate of 2.5 mL/s for all. Images were reconstructed using filtered back projection (FBP), and images in Groups B and C were additionally reconstructed using DL-ACE and DL-DN. Arterial attenuation, image noise, contrast-to-noise ratio (CNR), and subjective image quality were compared among five image sets. Results: Compared with Group A, Groups B and C received 23.7% lower radiation doses. With FBP, arterial attenuation was significantly higher in Groups B (435.8 ± 50.2 Hounsfield units [HU]) and C (391.8 ± 52.1 HU) than in Group A (321.1 ± 47.4 HU) (P < 0.001), while CNR did not differ significantly (Group A, 19.9 ± 4.7; Group B, 20.3 ± 3.8; and Group C, 18.4 ± 4.6) due to higher image noise in Groups B and C. After applying DL-ACE and DL-DN in Groups B and C, arterial attenuation increased by 45.4% and image noise decreased by 34.5%, resulting in significantly higher arterial attenuation, CNR, and subjective image quality compared with Group A (P < 0.001). Conclusion Cerebral CTA at 70-kVp using ultralow iodine enhanced arterial attenuation but increased image noise compared with the 100-kVp CTA protocol. DL-ACE and DL-DN significantly increased arterial attenuation and reduced image noise, resulting in higher CNR and better subjective image quality.

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: With the aging population and advancements in medical care worldwide, the number of older patients with end-stage kidney disease continues to rise. This study aimed to identify factors associated with osteoporosis and osteopenia in older patients undergoing incident hemodialysis and assess their impact on mortality. Methods: We analyzed a large multicenter retrospective cohort of patients aged ≥70 years undergoing incident hemodialysis to identify factors associated with osteoporosis using logistic regression analysis and to assess the association of death with osteoporosis and osteopenia using Cox multivariable analysis. Results: Among 710 patients, 39.0% and 19.6% had osteoporosis and osteopenia, respectively. Osteoporosis was significantly associated with female sex, a history of fractures, and the absence of phosphate binder use. During a median follow-up of 36.8 months, 348 participants (58.8%) died. Mortality rates were the highest in the osteoporosis group (79.8%), followed by the osteopenia (77.2%) and normal bone mineral density (BMD) groups (35.2%). Cox regression analysis revealed that even after adjusting for covariates, the osteoporosis group was significantly associated with a higher mortality risk than the normal BMD group. Osteoporosis at the start of hemodialysis was significantly associated with higher mortality. Conclusion We should consider the importance of bone health in patients undergoing incident hemodialysis and pay attention to the use of phosphate binders and fracture prevention.

Background: Obesity is a well-known risk factor for chronic kidney disease and its progression. However, the impact of obesity on the renal function of the elderly population is uncertain. We investigated the association between obesity and renal outcomes in the elderly. Methods: We analyzed 130,504 participants from the Korean National Health Insurance Service-Senior cohort. Obesity was classified according to body mass index (BMI), sex-specific waist circumference (WC), and the presence of metabolic syndrome. The primary outcome was renal function decline, defined as a decline in the estimated glomerular filtration rate (eGFR) of at least 50% from baseline or new-onset end-stage renal disease. Results: During a follow-up period of 559,531.1 person-years (median, 4.3 years), 2,486 participants (19.0%; incidence rate of 4.44 per 1,000 person-years) showed renal function decline. A multivariate Cox proportional hazards model revealed that BMI/WC was not associated with renal function decline. However, the group with metabolic syndrome had a significantly increased risk of renal function decline compared to the group without metabolic syndrome (adjusted hazard ratio [HR], 1.24; 95% confidence interval [CI], 1.13–1.36). Compared with the non-metabolic syndrome group, the adjusted HRs (95% CI) for participants with one through five components were 0.96 (0.84–1.11), 1.10 (0.96–1.27), 1.24 (1.06–1.45), 1.37 (1.12–1.66), and 1.99 (1.42–2.79), respectively (p for trend < 0.001). Conclusion In elderly Korean adults, metabolic syndrome and the number of its components were associated with a higher risk of renal function decline, but BMI or WC was not significant.

Objectives: Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research. Methods: Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes. Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes. Results: Data from 5460 ESD cases from 5250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days. Conclusions This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.

Purpose: Pediatric papillary thyroid cancer (PTC) is recommended to perform aggressive surgery to reduce the risk of recurrence.This study was designed to evaluate the concurrent association between multifocality, bilaterality, and the risk of recurrence in pediatric PTC. Materials and Methods: This retrospective cohort study included pediatric patients (age <19 years) who underwent total thyroidectomy for PTC between 1996 and 2014 in a single tertiary center. Clinicopathological parameters were analyzed to evaluate the prevalence of multifocality, bilaterality, recurrence, and their association. Results: We analyzed 58 pediatric patients with PTC. There was no factor related to the presence of multifocality or bilaterality in multivariate analysis. Also, in univariate analysis, multifocality and bilaterality were not independent risk factors of each other’s presentation (p=0.061 and p=0.061, respectively). Recurrence was observed in 19 (32.8%) patients. In multivariate analysis of recurrence, clear cell subtype, multifocality, and gross extrathyroidal extension (ETE) were independent risk factors (p=0.027, p=0.035, and p=0.038, respectively). Most recurrences (68.4%) happened during the first 4 years of follow-up after the initial thyroidectomy. Conclusion Multifocality and bilaterality were not independent risk factors of each other’s presentation; however, multifocality was the risk factor for recurrence in pediatric PTC. For pediatric PTC, close monitoring for recurrence within the initial 4 years is recommended, particularly in patients with clear cell subtype, multifocality, and gross ETE.

Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area.Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version.Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Background: The use of acellular dermal matrix (ADM) in breast reconstruction can inhibit capsular contracture, increasing the success rate of surgery. Adipose-derived stem cells (ADSCs) can effectively suppress foreign body reaction, which is a major cause of capsular contracture. This study aimed to elucidate the synergistic effects of combining ADSCs with ADM on capsule formation, utilizing a rat model. Methods: The study utilized 12 rats, equally divided into two experimental groups. Group A received silicone implants covered with ADM, while Group B was implanted with silicone prostheses wrapped in ADM, pre-seeded with ADSCs. Capsule formation was assessed through visual examination, histological analysis, and reverse transcription-polymerase chain reaction (RT-PCR) at 4 and 8 weeks post-implantation. Results: At 4 weeks, the mean capsular thickness was 177.16 μm in Group A and 170.76 μm in Group B; at 8 weeks, it was 196.69 μm in Group A and 176.10 μm in Group B. Statistical analysis showed no significant difference in capsule thickness between the groups (P>0.05). Histological findings indicated that Group A had more inflammatory cells and collagen fibers and reduced angiogenesis. RT-PCR showed that angiogenesis-promoting gene expression in Group B was 14% higher at 4 weeks and 156% higher at 8 weeks compared to Group A. Conclusion Although no statistically significant reduction in capsule thickness was observed, ADSC-seeded implants showed histological features associated with reduced inflammation and enhanced angiogenesis, suggesting potential benefits in capsule formation management.