Background: Programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) inhibitors are effective treatments for non-small cell lung cancer (NSCLC), but their use can lead to severe pneumonitis. This study aims to evaluate the utility of Krebs von den Lungen-6 (KL-6) for predicting and diagnosing PD-1/PD-L1 inhibitor-related pneumonitis in NSCLC patients. Methods: We conducted a prospective observational study at a university-affiliated tertiary hospital in Korea from February 2022 to June 2023. Baseline KL-6 levels were measured immediately before initiating PD-1/PD-L1 inhibitor therapy. In patients who developed pneumonitis, KL-6 levels were monitored every 1–2 weeks from the onset of pneumonitis. For patients without pneumonitis, KL-6 levels were measured every 6 weeks. We compared clinical characteristics and serial KL-6 levels between the pneumonitis and non-pneumonitis groups. Results: Eighteen patients were enrolled, with 11 developing pneumonitis. Baseline KL-6 levels did not significantly differ between the two groups (261 U/mL in the pneumonitis group vs. 373 U/mL in the non-pneumonitis group, p=0.375). In the pneumonitis group, KL-6 levels generally showed an upward trend, with a median of 412 U/mL at pneumonitis onset. Conversely, KL-6 levels in the non-pneumonitis group showed no clear overall change. Conclusion In this pilot study, baseline KL-6 was not clearly linked to PD-1/PD-L1 inhibitor-related pneumonitis in NSCLC patients. However, increases in KL-6 levels post-baseline were more frequently observed in patients who developed pneumonitis, including cases of all-cause pneumonitis.

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: Biliary atresia (BA) is a rare but progressive cholangiopathy and the leading cause of pediatric liver transplantation worldwide. The Korean Association of Pediatric Surgeons (KAPS) has conducted three national surveys (2001, 2011, and 2023) to assess long-term trends in the diagnosis, treatment, and outcomes of BA. This study provides a comparative analysis of the 2nd and 3rd national surveys, with reference to selected findings from the 1st survey. Methods: This study included 453 patients from the 3rd national survey (2011–2021) and 435 patients from the 2nd survey (2001–2010), all of whom underwent Kasai portoenterostomy. Data were collected via electronic case report forms from pediatric surgical centers nationwide. Comparisons were made regarding demographics, clinical features, diagnostic patterns, operative details, follow-up outcomes, and survival. Kaplan–Meier analysis was used to evaluate long-term survival. Results: The mean number of BA patients per year remained stable between surveys (43.5 in the 2nd, 41.18 in the 3rd), though centralization of care increased, with 61.5% of cases managed by two major institutions in the 3rd survey. The median age at surgery decreased, and the use of preoperative imaging (especially magnetic resonance cholangiopancreatography) increased. The 10-year native liver survival rate declined from 59.8% to 53.7%, while overall 10-year survival improved slightly (92.9% to 93.2%). Postoperative complications, such as cholangitis and liver failure, persisted but were better categorized. The 3rd survey also reported improved mortality (4.9%) and reduced follow-up loss (11.5%) compared to the 2nd survey. Conclusion While overall survival after Kasai operation has remained high and even improved, native liver survival has slightly declined. The findings reflect earlier diagnosis, more consistent diagnostic imaging, and increasing centralization of care. These trends underscore the importance of long-term nationwide data collection in guiding future strategies for BA management in Korea.

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.

Background/Aims: The prognosis of patients with idiopathic pulmonary fibrosis (IPF) and respiratory failure requiring mechanical ventilation is poor. Therefore, mechanical ventilation is not recommended. Recently, outcomes of mechanical ventilation, including those for patients with IPF, have improved. The aim of this study was to investigate changes in the use of mechanical ventilation in patients with IPF and their outcomes over time. Methods: This retrospective, observational cohort study used data from the National Health Insurance Service database. Patients diagnosed with IPF between January 2011 and December 2019 who were placed on mechanical ventilation were included. We analyzed changes in the use of mechanical ventilation in patients with IPF and their mortality using the Cochran- Armitage trend test. Results: Between 2011 and 2019, 1,227 patients with IPF were placed on mechanical ventilation. The annual number of patients with IPF with and without mechanical ventilation increased over time. However, the ratio was relatively stable at approximately 3.5%. The overall hospital mortality rate was 69.4%. There was no improvement in annual hospital mortality rate. The overall 30-day mortality rate was 68.7%, which did not change significantly. The overall 90-day mortality rate was 85.3%. The annual 90-day mortality rate was decreased from 90.9% in 2011 to 83.1% in 2019 (p = 0.028). Conclusions Despite improvements in intensive care and ventilator management, the prognosis of patients with IPF receiving mechanical ventilation has not improved significantly.

Purpose: This study provides insights into the prevalence at birth, clinical characteristics, and outcomes of gastroschisis and omphalocele in Korea over the past decade, addressing the lack of localized data despite advanced healthcare capabilities. Methods: The study retrospectively analyzed data from 20 pediatric surgical centers in Korea from January 2012 to December 2021, including 269 patients diagnosed with gastroschisis or omphalocele. Data variables included gender, gestational age, birth weight, associated anomalies, type of defect, surgical interventions, and outcomes. Results: The study covered 269 patients, with 80 gastroschisis and 189 omphalocele cases. Gastroschisis prevalence at birth remained stable at 2.15 per 100,000 live births, while omphalocele increased to 5.08 per 100,000. Both conditions had similar gender ratios (0.95). Gastroschisis patients had lower birth weights (2,463.90±505.50 g) and smaller head circumferences (31.97±1.86 cm) compared to omphalocele patients (2,757.65±761.24 g, 32.78±2.64 cm). Omphalocele cases had more associated anomalies, especially cardiovascular issues. Prenatal diagnosis rates were high: 93.7% for gastroschisis and 86.4% for omphalocele. About 96.3% of gastroschisis and 84.1% of omphalocele patients were born in their treatment hospitals. Gastroschisis patients underwent surgery sooner (average 3.5 days) and started feeding later (16.5 days) than omphalocele patients (average 56.5 days to surgery, 6.6 days to start feeding). Hospital stays and follow-up durations were similar, averaging around 782.6 days for gastroschisis and 800.3 days for omphalocele patients. Survival rates were 89.7% for gastroschisis and 87.1% for omphalocele. Conclusion The study highlights the need for early diagnosis, centralized care, and specialized surgical approaches to optimize outcomes for gastroschisis and omphalocele patients in Korea. Enhanced prenatal screening and surgical protocols are recommended to improve these patients' prognosis.

Purpose: This study was conducted to assess the antidepressant effects of capsaicin in chronic depressive rats and elucidate the mechanism underlying its effects. Methods: Male Wistar rats (280~320 g, 8 weeks of age) were subjected to depression induced by chronic unpredictable mild stresses. The rats were exposed to 8 kinds of stresses for 8 weeks. In the last 2 weeks, fluoxetine or capsaicin was injected subcutaneously. The dose of fluoxetine was 10 mg/kg (body weight), while the doses of capsaicin consisted of low (1 mg/kg), middle (5 mg/kg), and high (10 mg/kg). The forced swim test (FST) was conducted to evaluate the immobility time of rats. The immobility time indicates despair, one of symptoms of depression. The change of tryptophan hydroxylase (TPH) in the dorsal raphe was investigated using immunohistochemistry. In the hippocampus cornu ammonis (CA) 1 and 3, glucocorticoid receptor (GR) expression was measured. Results: The immobility time in the FST was significantly lower (p < .05) in the low-dose (M = 32.40 ± 13.41 seconds) and middle-dose (M = 28.48 ± 19.57 seconds) groups than in the non-treated depressive rats (M = 90.19 ± 45.34 seconds). The amount of TPH in the dorsal raphe was significantly higher (p < .05) in the middle-dose (M = 249.17 ± 35.02) and high-dose (M = 251.0 ± 56.85) groups than in the non-treated depressive rats (M = 159.78 ± 41.16). However, GR expression in the hippocampus CA1 and CA3 did not show significant differences between the non-treated depressive rats and the capsaicin-injected rats. Conclusion This study suggests that capsaicin produces an antidepressant-like effect on chronic unpredictable mild stress-induced depression in rats via the serotonin biosynthesis pathway.

Background/Aims: Posthepatectomy liver failure (PHLF) is a major complication that increases mortality in patients with hepatocellular carcinoma after surgical resection. The aim of this retrospective study was to evaluate the utility of magnetic resonance elastography-assessed liver stiffness (MRE-LS) for the prediction of PHLF and to develop an MRE-LS-based risk prediction model. Methods: A total of 160 hepatocellular carcinoma patients who underwent surgical resection with available preoperative MRE-LS data were enrolled. Clinical and laboratory parameters were collected from medical records. Logistic regression analyses were conducted to identify the risk factors for PHLF and develop a risk prediction model. Results: PHLF was present in 24 patients (15%). In the multivariate logistic analysis, high MRE-LS (kPa; odds ratio [OR] 1.49, 95% confidence interval [CI] 1.12 to 1.98, p=0.006), low serum albumin (≤3.8 g/dL; OR 15.89, 95% CI 2.41 to 104.82, p=0.004), major hepatic resection (OR 4.16, 95% CI 1.40 to 12.38, p=0.014), higher albumin-bilirubin score (>–0.55; OR 3.72, 95% CI 1.15 to 12.04, p=0.028), and higher serum α-fetoprotein (>100 ng/mL; OR 3.53, 95% CI 1.20 to 10.40, p=0.022) were identified as independent risk factors for PHLF. A risk prediction model for PHLF was established using the multivariate logistic regression equation. The area under the receiver operating characteristic curve (AUC) of the risk prediction model was 0.877 for predicting PHLF and 0.923 for predicting grade B and C PHLF. In leave-one-out cross-validation, the risk model showed good performance, with AUCs of 0.807 for all-grade PHLF and 0. 871 for grade B and C PHLF. Conclusions Our novel MRE-LS-based risk model had excellent performance in predicting PHLF, especially grade B and C PHLF.

Background: Cardiac dysfunction patients have long been considered at high risk of reintubation. However, it is based on past studies in which only conventional oxygen therapy was applied after extubation. We investigated association between cardiac dysfunction and reintubation rate in situation where high-flow nasal cannula (HFNC) was widely used during post-extubation period. Methods: We conducted a retrospective observational cohort study of patients treated with HFNC after planned extubation in medical intensive care unit of single tertiary center. Patients were divided into normal function group (ejection fraction [EF] ≥45%) and cardiac dysfunction group (EF <45%). The primary outcome was reintubation rate within 72 hours following extubation. Results: Of 270 patients, 35 (13%) had cardiac dysfunction. Baseline characteristics were similar in both groups. There were no differences in the changes in vital signs between the two groups during the first 12 hours after extubation except diastolic blood pressure. The reintubation rates were 20% and 17% for cardiac dysfunction group and normal function group, respectively (p=0.637). In a multivariate Cox regression analysis, cardiac dysfunction was not associated with an increased risk of reintubation within 72 hours following extubation (hazard ratio, 1.56; p=0.292). Conclusion Cardiac dysfunction was not associated with increased reintubation rate within 72 hours when HFNC is immediately applied after planned extubation.

Objective: High-quality intensive care, including targeted temperature management (TTM) for patients with postcardiac arrest syndrome, is a key element for improving outcomes after out-of-hospital cardiac arrest (OHCA). We aimed to assess the status of postcardiac arrest syndrome care, including TTM and 6-month survival with neurologically favorable outcomes, after adult OHCA patients were treated with TTM, using data from the Korean Hypothermia Network prospective registry. Methods: We used the Korean Hypothermia Network prospective registry, a web-based multicenter registry that includes data from 22 participating hospitals throughout the Republic of Korea. Adult comatose OHCA survivors treated with TTM between October 2015 and December 2018 were included. The primary outcome was neurological outcome at 6 months. Results: Of the 1,354 registered OHCA survivors treated with TTM, 550 (40.6%) survived 6 months, and 413 (30.5%) had good neurological outcomes. We identified 839 (62.0%) patients with preClinsumed cardiac etiology. A total of 937 (69.2%) collapses were witnessed, shockable rhythms were demonstrated in 482 (35.6%) patients, and 421 (31.1%) patients arrived at the emergency department with prehospital return of spontaneous circulation. The most common target temperature was 33°C, and the most common target duration was 24 hours. Conclusion The survival and good neurologic outcome rates of this prospective registry show great improvements compared with those of an earlier registry. While the optimal target temperature and duration are still unknown, the most common target temperature was 33°C, and the most common target duration was 24 hours.