Background: DNA methylation is under investigation as an early diagnostic biomarker for cancers such as hepatocellular carcinoma (HCC). p21-activated protein kinase 1 (PAK1) demonstrates a high methylation tendency in HCC. We assessed the diagnostic and prognostic performance of PAK1 methylation in liver transplantation (LT) recipients with and without HCC. Methods: To assess PAK1 methylation, stored pretransplant blood samples from LT recipients were analyzed by droplet digital polymerase chain reaction. Results: This study included 274 patients with HCC and 100 control patients without the disease. Ten-year survival rates in the HCC and control groups were 60.5% and 80.6%, respectively (P=0.001). The 10-year HCC recurrence rate was 39.0%. Ten-year survival rates in the HCC recurrence and nonrecurrence groups were 13.3% and 91.2%, respectively (P<0.001); median PAK1 methylation levels in the control and HCC groups were 50.0 and 108.0 copies (P=0.102). The area under the receiver operating characteristic curve was 0.599, and the Youden J index was 0.199, indicating 57.9% sensitivity and 62.0% specificity at a cutoff of 78 copies. With a cutoff of 5 copies, sensitivity was 94.1% and specificity was 14.0%. The positive likelihood ratio was 1.09 and the negative likelihood ratio was 0.42, indicating diagnostic accuracy below α-fetoprotein and protein induced by vitamin K absence or antagonist-II. PAK1 cutoffs of 5 and 10 copies did not affect HCC recurrence, but a cutoff of 2 copies appeared associated with lower recurrence. Conclusions These data suggest that PAK1 methylation is not a clinically useful biomarker for HCC in LT recipients. New DNA methylation biomarkers are required for early diagnosis.

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: A decellularized liver scaffold (DLS) is a three-dimensional acellular extracellular matrix created by removing cellular components from liver tissue. Hepatocellular carcinoma (HCC) organoids represent a useful experimental model. Methods: HCC organoids from patient-derived xenografts (PDX), liver organoids, and HepG2 cells were expanded by cultivation within a murine DLS. Results: HCC and liver organoids were generated from HCC PDX and human liver tissues, respectively. Expression levels of hepatocyte paraffin 1 (HepPar1), epithelial cell adhesion molecule (EpCAM), alpha-fetoprotein, keratin-7, and keratin-19 were detected in normal liver tissue, HCC tissue, HCC PDX, and HCC organoids. Fifteen murine DLSs were created, and the complete absence of liver cells was confirmed histologically by Masson trichrome and periodic acid–Schiff staining. Culture of HCC organoids in the DLS resulted in the expansion of numerous HCC cells scattered throughout the DLS framework. Keratin-7 expression was abundant, indicating widely dispersed progenitor cells. In contrast, cultivation of HepG2 cells within the DLS resulted in sparse cell distribution throughout the scaffold. Human hepatocyte organoids could not be cultivated successfully within the murine DLS framework. Conclusions The DLS collagen framework facilitates the proliferation of HCC organoids. Thus, cultivating HCC organoids within a DLS appears to represent an effective method for rapid cell expansion, although it was ineffective for HepG2 cells and liver organoids. Further studies are required to validate the biological and oncological equivalence between seeded HCC organoids and those rapidly expanded within a DLS.

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: The Korean Association of Pediatric Surgeons (KAPS) conducts annual nationwide surveys on various aspects of pediatric surgical diseases, with the results being discussed during KAPS’s annual spring meetings. Methods: KAPS conducted two national surveys, in 1995 and 2016, to investigate esophageal atresia (EA) with or without tracheoesophageal fistula (TEF). The authors analyzed data from these surveys to identify differences or changes in the annual occurrence, demographic characteristics, clinical presentation, preoperative diagnostic methods, anatomical type, associated anomalies, surgical treatment, and postoperative outcomes among patients with EA/TEF treated by KAPS members. Results: The first and second national surveys included 148 and 211 patients with EA/TEF, respectively. Excessive salivation was the most prevalent clinical symptom in both surveys. Type C was the most common form of EA/TEF in both surveys. The first survey included 126 patients, all of whom underwent open surgery. In the second survey, 152 (78.4%) of 194 patients underwent open surgery, while 34 (17.5%) underwent thoracoscopic surgery. Primary esophageal repair was performed on 96 (76.2%) of 126 patients in the first survey and on 160 (82.5%) of 194 patients in the second survey. Anastomotic strictures developed in 21.4% and 32.5% of patients, anastomotic leakage in 22.2% and 10.3%, recurrent fistula in 2.4% and 4.2% during the first and second surveys, respectively. The respective survival rates for group A were 90.2% and 98.3% in the first and second surveys. For group B, the rates were 73.9% and 98.1%, and for group C, they were 34.5% and 68.1%, respectively, according to the Waterston classifications. Conclusion These nationwide surveys provide comprehensive information on the status, detailed treatment, and outcomes for Korean pediatric patients with EA/TEF. They are anticipated to be an invaluable resource and guide for pediatric surgeons seeking to expand their knowledge on EA/TEF and its treatment options.

Objectives: This study was conducted to evaluate the effects of a nutrition education program on metabolic syndrome in middle-aged Korean adults. Methods: A total of 411 Korean adults 30–59 years of age were allocated randomly into three groups: the nutrition education group for promoting Han-sik consumption (HG), the nutrition education group for eating balanced diet (EG), and the control group (CG). The HG and EG received four face-to-face nutrition education sessions over 16 weeks to improve nutritional problems based on the individual’ usual diet. Effectiveness of the program was evaluated with the differences of self-reported dietary behaviors, dietary intakes, anthropometric measurements and biochemical indices between the baseline and the end of the nutrition education program. The changes within groups were analyzed using paired t-test and McNemar test and effectiveness among three groups was analyzed by repeated analysis of variance. Results: After the nutrition education, the percentages of participants who achieved the recommended food group consumption in the Korean Food Guidance Systems significantly increased in HG (P = 0.022). Body weight (P = 0.007), body mass index (P = 0.002), and triglycerides (P = 0.002) significantly decreased in HG. Waist circumference and diastolic blood pressure decreased in all three groups (P < 0.05). Conclusions This study found that tailored nutrition education program for middle aged Korean adults showed beneficial effects on improving dietary behaviors and metabolic syndrome risk factors. Further studies are needed to assess the long-term effects of the nutrition education programs on metabolic syndrome risks.

Coronavirus disease 2019 (COVID-19) vaccination in immunocompromised, especially transplant recipients, may induce a weaker immune response. But there are limited data on the immune response after COVID-19 vaccination in liver transplant (LT) recipients, especially on the comparison of Ab responses after different vaccine platforms between mRNA and adenoviral vector vaccines. Thus, we conducted a prospective study on LT recipients who received two doses of the ChAdOx1 nCoV-19 (ChAdOx1), mRNA-1273, or BNT162b2 vaccines compared with healthy healthcare workers (HCWs). SARS-CoV-2 S1-specific IgG Ab titers were measured using ELISA.Overall, 89 LT recipients (ChAdOx1, n=16 [18%]) or mRNA vaccines (mRNA-1273 vaccine, n=23 [26%]; BNT162b2 vaccine, n=50 [56%]) received 3 different vaccines. Of them, 16 (18%) had a positive Ab response after one dose of COVID-19 vaccine and 62 (73%) after 2 doses. However, the median Ab titer after two doses of mRNA vaccines was significantly higher (44.6 IU/ml) than after two doses of ChAdOx1 (19.2 IU/ml, p=0.04). The longer time interval from transplantation was significantly associated with high Ab titers after two doses of vaccine (p=0.003). However, mycophenolic acid use was not associated with Ab titers (p=0.53). In conclusion, about 3-quarters of LT recipients had a positive Ab response after 2 doses of vaccine, and the mRNA vaccines induced higher Ab responses than the ChAdOx1 vaccine.

At the end of 2019, the cause of pneumonia outbreaks in Wuhan, China, was identified as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In February 2020, the World Health Organization named the disease cause by SARS-CoV-2 as coronavirus disease 2019 (COVID-19). In response to the pandemic, the Korean Cancer Association formed the COVID-19 task force to develop practice guidelines. This special article introduces the clinical practice guidelines for cancer patients which will help oncologists best manage cancer patients during the COVID-19 pandemic.