Purpose: To report a nationwide survey on neuroblastoma conducted by the Korean Association of Pediatric Surgeons (KAPS) in 2020. Methods: The clinical data of pediatric patients diagnosed with and treated for neuroblastoma from 2005 to 2019 in 19 hospitals of KAPS members were collected. Survival and prognostic factor analyses were performed using the log rank test and Cox proportional hazard analysis. A p-value <0.05 was considered significant. Results: A total of 669 patients with neuroblastoma were registered for the study. The results were presented and discussed at the 36th annual meeting of the KAPS, which was held in Seoul on August 21, 2020. Conclusion This study provides information on patient demographics, prognostic outcomes, and comprehensive treatment outcomes for neuroblastoma. The study is expected to be an important reference for improving pediatric surgeons’ understanding and treatment of neuroblastoma.

Purpose: This study aims to investigate and compare the incidence, demographic characteristics, clinical manifestations, preoperative diagnostic methods, anatomical classifications, associated anomalies, operative treatments, and postoperative outcomes of patients with intestinal atresia treated by the members of the Korean Association of Pediatric Surgeons (KAPS) through three nationwide surveys. Methods: KAPS conducted 3 national surveys in 1998, 2010, and 2024 to examine the patients diagnosed with intestinal atresia. In preparation for the survey, we developed a customized case registration form to obtain data on patient sex, birth weight, gestational age, clinical manifestations, preoperative diagnostic methods, anatomical types, associated anomalies, operative treatments, and postoperative outcomes. Authorized KAPS members completed the case registration form. Results: The first, second, and third national surveys included 218, 222, and 236 individuals diagnosed with intestinal atresia, respectively. The male-to-female ratios were 1.5:1, 1.1:1, and 1.1:1, respectively. The first, second, and third national surveys revealed that 34.3%, 43.3%, and 53.4% of patients were born before 37 weeks of gestation, respectively. Additionally, 28.7%, 32.0%, and 40.7% of patients had a birth weight under 2,500 g. In the third national survey, duodenoduodenostomy was the most common procedure, performed in 70 out of 82 patients diagnosed with duodenal atresia. Resection and anastomosis were the main surgical procedures conducted in 47 out of 54 cases of jejunal atresia and 74 out of 92 cases of ileal atresia. The mortality rates in the first, second, and third national surveys were 13.8%, 3.6%, and 1.3% respectively, with the lowest rate observed in the third national survey. Conclusion These national surveys offer valuable insights into the current state of intestinal atresia, including specific surgical interventions and postoperative outcomes in South Korea. For pediatric surgeons aiming to enhance their understanding of intestinal atresia and its treatment options, these surveys could be an indispensable resource and guide.

Patients with sensitization and blood type O experience increased waiting times for deceased-donor kidney transplantation (DDKT). While allocation benefits are needed to resolve inequity in DDKT opportunity, whether DDKT has comparable outcomes in this disadvantaged population requires further study. This study assessed these outcomes and developed a new allocation system that balances equity and utility. Methods: Patients from national and hospital cohorts from two centers in Korea were categorized as B1 to B4 (according to panel reactive antibody [PRA] positivity and ABO blood type) and A1 to A4 (based on the maximal PRA% and blood type), respectively. Competing risk and Cox regression analyses were performed to assess the effects of PRA and blood type on graft failure and mortality, respectively. Based on DDKT opportunities and posttransplant outcomes, a new scoring system for kidney allocation was developed. Results: The national and hospital cohorts included 3,311 and 819 patients, respectively, who underwent DDKT. Despite the disparities in DDKT opportunities, the graft failure rates and mortality did not differ among the different PRA and blood type groups. Furthermore, posttransplantation outcomes did not differ according to the categories with different DDKT opportunities. A new scoring system to provide additional points to disadvantaged populations was developed based on the hazard ratios for DDKT. Conclusion: A new allocation approach based on PRA and ABO blood types offers benefits to disadvantaged patients with fewer DDKT opportunities and could enhance equity without sacrificing utility in Korea, which has a long waiting time for DDKT.

Purpose: This study investigated the adjunctive effect of light-emitting diodes (LEDs) in the treatment of experimental periodontitis. Methods: Experimental periodontitis was induced by placing ligatures around the mandibular second, third, and fourth premolars of 6 beagles for 3 months. After ligature removal, periodontitis progressed spontaneously for 2 months. The animals’ hemimandibles were allocated among the following 3 groups: 1) no treatment (control), 2) scaling and root planing (SRP), and 3) SRP with LED irradiation at 470-nm and 630-nm wavelengths (SRP/LED). The probing pocket depth (PPD) and gingival recession (GR) were measured at baseline, 6 weeks, and 12 weeks. The clinical attachment level (CAL) was calculated. After 12 weeks, histological and histomorphometric assessments were performed. The distances from the gingival margin to the apical extent of the junctional epithelium (E) and to the connective tissue (CT) attachment were measured, as was the total length of soft tissue (ST). Results: PPD and CAL increased at 12 weeks compared with baseline in the control group (6.31±0.43 mm to 6.93±0.50 mm, and 6.46±0.60 mm to 7.61±0.78 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP group (6.01±0.59 to 4.81±0.65 mm, and 6.51±0.98 to 5.39±0.93 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP/LED group (6.03±0.39 to 4.46±0.47 mm, and 6.11±0.47 to 4.78±0.57 mm, respectively). The E/ST and CT/ST ratios significantly differed among the 3 groups (P<0.05). The clinical parameters and histologic findings demonstrated that 470-nm and 630-nm wavelength LED irradiation accompanying SRP could improve treatment results. Conclusions Within the study limitations, 470 nm and 630 nm wavelength LED irradiation might provide additional benefits for periodontitis treatment.

Background: The pragmatic role of dynamic contrast-enhanced magnetic resonance lymphangiography (DCMRL) needs to be evaluated and compared across distinct lymphatic disorders. We aimed to evaluate the performance of DCMRL for identifying the underlying causes of lymphatic disorders and to define the potential benefit of DCMRL for planning lymphatic interventions. Methods: Patients who underwent DCMRL between August 2017 and July 2022 were included in this retrospective analysis. DCMRL was performed with intranodal injection of a gadolinium-based contrast medium through inguinal lymph nodes under local anesthesia.Technical success of DCMRL and feasibility of percutaneous embolization were assessed based on the lymphatic anatomy visualized by DCMRL. Based on the underlying causes, clinical outcomes were evaluated and compared. Results: Seventy consecutive patients were included. The indications were traumatic chylothorax (n = 42), traumatic chylous ascites (n = 11), and nontraumatic lymphatic leak (n = 17). The technical success rate of DCMRL was the highest in association with nontraumatic lymphatic disorders (94.1% [16/17]), followed by traumatic chylothorax (92.9% [39/42]) and traumatic chylous ascites (81.8% [9/11]). Thirty-one (47.7%) patients among 65 patients who underwent technically successful DCMRL had feasible anatomy for intervention. Clinical success was achieved in 90.3% (28/31) of patients with feasible anatomy for radiologic intervention, while 62.5% (10/16) of patients with anatomical challenges showed improvement. Most patients with traumatic chylothorax showed improvement (92.9% [39/42]), whereas only 23.5% (4/17) of patients with nontraumatic lymphatic disorders showed clinical improvement. Conclusion DCMRL can help identify the underlying causes of lymphatic disorders.The performance of DCMRL and clinical outcomes vary based on the underlying cause.The feasibility of lymphatic intervention can be determined using DCMRL, which can help in predicting clinical outcomes.

Purpose: Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. Materials and Methods: From January 2001 to December 2015, data of pediatric patients (0–18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. Results: Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range 0-225.5) and median follow-up duration was 88.5 months (range 0-211.6). Overall, 32 patients died, of whom 17, 11, 1, and 3 died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). Conclusion The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea.

Purpose: Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers (ARBs) are frequently employed to counteract the detrimental effects of proteinuria on glomerular diseases. However, the effects of ARBs remain poorly examined in pediatric patients with immunoglobulin A (IgA) nephropathy. Herein, we evaluated the efficacy and safety of losartan, an ARB, in pediatric IgA nephropathy with proteinuria. Methods: This prospective, single-arm, multicenter study included children with IgA nephropathy exhibiting proteinuria. Changes in proteinuria, blood pressure, and kidney function were prospectively evaluated before and 4 and 24 weeks after losartan administration. The primary endpoint was the difference in proteinuria between baseline and 24 weeks. Results: In total, 29 patients were enrolled and received losartan treatment. The full analysis set included 28 patients who received losartan at least once and had pre- and post-urinary protein to creatinine ratio measurements (n=28). The per-protocol analysis group included 22 patients who completed all scheduled visits without any serious violations during the study period. In both groups, the mean log (urine protein to creatinine ratio) value decreased significantly at 6 months. After 24 weeks, the urinary protein to creatinine ratio decreased by more than 50% in approximately 40% of the patients. The glomerular filtration rate was not significantly altered during the observation period. Conclusions Losartan decreased proteinuria without decreasing kidney function in patients with IgA nephropathy over 24 weeks. Losartan could be safely employed to reduce proteinuria in this patient population. ClinicalTrials.gov trial registration (NCT0223277)

Objectives: ：A growing body of evidence links type 2 diabetes (T2D) with a neurodegenerative disease (ND) such as Alzheimer’s disease and Parkinson’s disease. The purpose of this study is to investigate the relationship between NDs and the development of T2D by comparing the incidence of T2D in a group of various NDs (ND group) and control group. Methods: ：A population-based 10-year follow-up study was conducted using the Korean National Health Information Database for 2002-2015. We used a retrospective cohort study design to investigate the association of ND with T2D occurrence. The study population included ND (n=8,814) and control (n=37,970) groups, all aged 60 years or over. The Kaplan-Meier method was used to estimate the risk of developing T2D as a function of time. Cox proportional hazards regression models were used to evaluate the relationship between ND and T2D. Results: ：T2D was developed in a significantly higher percentage of patients in the ND group (53.6%) than in the control group (44.7%). The ND group increased the risk of T2D (HR, 1.43; 95% CI, 1.38-1.47). About onethird of patients in both groups were additionally diagnosed with another ND before the occurrence of T2D during a 10-year follow-up period. When compared to those who did not have another ND during the follow-up period, the incidence of T2D in those who were additionally diagnosed with another ND was higher in both the ND and control groups. Conclusions ：The ND group had about 1.4 times higher risk of developing T2D than the control group. Our results showed a positive association between ND and T2D.

Five-FU is a potent chemotherapeutic agent for suppressing endothelial cell growth. The purpose of this study was to investigate the usefulness of local peritumor injection of 5-FU for patients with advanced gastric cancer (AGC) for the prevention of anemia. Between January 2020 and January 2022, patients aged 18 years or older with AGC and moderate anemia were included. A total of 200 mg of 5-FU was injected per session at ten points of the lesion (20 mg at each point) every 7 days for 4 to 12 weeks. Patients received a blood test for toxicity at every cycle. From one of these patients, endoscopic biopsy specimens were taken from gastric cancer before and after injecting 5-FU for immunostaining. A total of five AGC patients participated in this study. For most patients, hemoglobin levels were maintained without transfusions during 5-FU injection, and expression levels of thrombospondin-1 was increased after injection compared to those before injection. Blood test results during 5-FU injection showed no significant change in serum glutamic oxalacetic transaminase/glutamic pyruvic transaminase, total bilirubin, or creatinine level. The results of this study showed the possibility of local peritumor 5-FU injection as a treatment for relieving anemia of patients with gastric cancer.

Objectives: Clinicians often depend on the results of the the multiple sleep latency test (MSLT) for diagnosing narcolepsy, but the diagnosis can be confusing when there is a co-existence of obstructive sleep apnea (OSA). This study is aimed to address the diagnostic tendency and the strategies of treatment for narcolepsy and other hypersomnia in the grey zone. Methods: We performed a web-based survey of Korean neurologists who were interested in narcolepsy and had experience with sleep studies. Results: The results of this survey present their concerns according to the severity of comorbid OSA in analyzing the results of the MSLT. Conclusions This study also might help by providing the opinions of experienced Korean neurologists for the assessment and management of excessive daytime sleepiness.