Replacing the retrohepatic inferior vena cava (IVC) following concurrent resection of the IVC and tumor-involved liver is an emerging surgical technique in living donor liver transplantation (LDLT), particularly for managing hepatocellular carcinomas near the IVC. This approach makes the extent of hepatectomy in LDLT comparable to that of deceased donor liver transplantation. We report a pediatric LDLT case involving IVC and portal vein (PV) replacement with an iliac vein homograft to treat advanced hepatoblastomas. The patient was a 24-month-old girl weighing 9.1 kg, presenting with large, multiple hepatoblastomas infiltrating the retrohepatic IVC and PV. After a 2-week waiting period, a cold-stored iliac vein graft was obtained, and the transplantation was performed using a left lateral section graft from her father.A 4-cm iliac vein homograft was anastomosed between the suprahepatic and suprarenal IVC stumps. The liver graft was implanted following standard procedures, with the PV reconstructed via a telescope-shaped anastomosis using the vein graft interposition. The patient experienced an uncomplicated recovery and is currently receiving scheduled adjuvant chemotherapy. In conclusion, IVC and PV replacement with vein homografts represents a feasible and effective surgical strategy for pediatric LDLT patients with advanced liver malignancies involving vascular invasion.

Purpose: Malignant hepatocellular neoplasm, not otherwise specified (HCN-NOS) is a provisional diagnostic entity, characterised by intermediate or a combination of hepatoblastoma and pediatric hepatocellular carcinoma (p-HCC) features. We compared the characteristics of HCN-NOS with hepatoblastoma and p-HCC. Materials and Methods: The records of 148 pediatric patients diagnosed with hepatocellular malignancy after resection were retrieved from the institutional database. Clinical parameters and histopathology slides were reviewed to re-establish each patient’s diagnosis. Molecular analyses were conducted in 37 patients. Results: Patients were profiled as 21 (14.2%) with HCN-NOS, 109 (73.6%) with hepatoblastoma, and 18 (12.2%) with p-HCC. The median age was 8.6 years in HCN-NOS, 1.2 years in hepatoblastoma, and 7.9 years in p-HCC. Background liver disease was frequently observed in p-HCC (11/18, 61%) but infrequent in HCN-NOS (4/21, 19%) and hepatoblastoma (4/109, 3.7%). HCN-NOS presented with a more advanced PRETEXT stage (p=0.012), metastasis (p < 0.001), and lymphovascular invasion (p < 0.001) than hepatoblastoma and p-HCC. Patients with HCN-NOS received longer cycles of preoperative chemotherapy; however, they reported a lower decrease in serum alpha-fetoprotein and tumor size than hepatoblastoma (p=0.043, p=0.004, and p=0.044, respectively). HCN-NOS was an independent poor prognostic factor for event-free survival (hazard ratio, 4.968; 95% confidence interval, 2.004 to 12.32; p < 0.001). Conclusion The possibility of HCN-NOS should be considered in pediatric patients with liver cancer, especially those ≥ 5 years old with no background liver disease. Because HCN-NOS exhibits poor chemoresponsiveness and unfavourable postoperative prognosis, liver transplantation should be strongly considered.

In children with biliary atresia, recurrent episodes of cholangitis often lead to portal vein (PV) phlebosclerosis. We report a case of pediatric living donor liver transplantation (LDLT) for biliary atresia with PV occlusion and a large splenorenal shunt. A 3-year-5-month-old girl was diagnosed with syndromic biliary atresia and polysplenia. Because the patient’s condition progressively deteriorated with worsening jaundice, we opted to perform LDLT using a left lateral section graft from her father. The recipient’s native PV was severely atrophic and completely occluded, and the collateral veins around the hepatoduodenal ligament were too small to serve as a viable source of portal inflow.Consequently, renoportal anastomosis (RPA) was selected as an alternative approach.Iliac vein interposition was performed to provide a new portal inflow source, and anatomy-compliant PV reconstruction was performed. The patient recovered from transplant surgery, but PV conduit stenosis occurred with the development of ascites 2 months posttransplant. This RPA-related vascular complication was resolved through percutaneous balloon angioplasty of the PV conduit. The patient has been doing well for 6 months posttransplantation. This case demonstrates that RPA can represent a viable reconstructive option for PV inflow in liver transplantation for pediatric patients with phlebosclerotic PV and prominent splenorenal shunt.

Replacement of the retrohepatic inferior vena cava (IVC) after concurrent resection of IVC and tumor-bearing liver is regarded as a feasible living donor liver transplantation (LDLT) technique to cope with tumors around the IVC. This method can make the resection extent of LDLT comparable to that of deceased-donor liver transplantation. We present one pediatric LDLT case with IVC replacement using an enlarged iliac vein conduit to treat advanced hepatoblastoma. The patient was a 33-monthold and 12 kg-weighing girl suffering from large multiple hepatoblastomas invading the retrohepatic IVC. At 2-month waiting after deciding LDLT, we obtained a coldstored iliac vein graft and LDLT was performed with the father’s left lateral section graft. A 1.3 cm-wide and 10 cm-long iliac vein was transformed to be a 2 cm-wide and 5 cm-long vein graft through a double-barrel unification venoplasty. The left lateral section graft was implanted along the standard procedure of LDLT. The patient recovered uneventfully and is undergoing scheduled adjuvant chemotherapy. IVC replacement with vein homograft is a feasible option for LDLT in pediatric patients with advanced liver malignancy.

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.

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: Complicated vascular anomalies, characterized by encasing vital organ or diffusely locating unresectable lesion, pose therapeutic challenges with limited response to conventional treatment such as surgical resection or sclerotherapy. Sirolimus, an mammalian target of rapamycin inhibitor, has shown promising therapeutic effects in patients with vascular anomalies by inhibiting vascular endothelial growth factor, as reported in several studies. Here, we analyzed the treatment outcomes of patients who received sirolimus for complicated vascular anomalies at our institution. Methods: Patients treated with sirolimus at the Department of Pediatric Surgery, Asan Medical Center from January 2018 to December 2021 were included. Sirolimus was administered twice daily at a dose of 0.8 mg per body surface area (BSA), with dose adjustments to achieve a target drug concentration of 8–12 ng/mL. Adverse drug effects and therapeutic responses were periodically assessed. Treatment efficacy was evaluated based on clinical findings pre- and post-sirolimus administration, absolute volume reduction of lesions through imaging tests (magnetic resonance imaging; MRI), and relative volume reduction adjusted to the patient's BSA. Results: There were 16 females (50.0%) and 16 males (50.0%), with a median follow-up period of 41 months after sirolimus administration. Vascular anomaly types included lymphatic malformations (41%), venous malformations (28%), lymphovenous malformations (19%), and others (12.5%). The most common adverse effect was oral ulcer (6 patients). MRI volumetry revealed volume decreases in 17 patients (53.1%) with 22 patients (71%) exhibited lesion decreases relative to BSA. Notably, 9 patients (28.1%) had markedly decreased volume reduction based on absolute volume, and 12 (38.7%) based on volume compared to BSA. Conclusion Over a 2-year follow-up, sirolimus was effective in treating patients with complicated vascular anomalies, when administered with cautious consideration of side effects. A multidisciplinary approach is needed for evaluating treatment outcomes in these patients, necessitating further long-term research on adverse effects.

Liver transplantation is accepted as an effective therapeutic option for unresectable hepatoblastoma. We present a pediatric case of hepatoblastoma patient with portal vein (PV) tumor thrombosis (PVTT) that occluded the main PV completely despite aggressive neoadjuvant chemotherapy. The patient was a 4-year and 2-month-old 17-kg boy suffering from hepatoblastoma with PVTT, which was partially regressed by neoadjuvant chemotherapy. Viable PVTT remained after right trisectionectomy and repetition of systemic chemotherapy. To remove the tumor completely, we performed living donor liver transplantation (LDLT) using his father’s left liver graft.The native PV was completely occluded with PVTT and abundant pericholedochal collaterals developed. The native PV was meticulously dissected to fully expose the superior mesenteric vein-splenic vein confluence. This confluence portion was deeply clamped and opened to use as a viable PV inflow source. A cold-stored fresh external iliac vein homograft was anastomosed to the confluence portion as an end-to-end fashion and passed through the native retropancreatic PV tract after mechanical dilatation of the tract. Left liver graft implantation was performed using standard procedures of pediatric LDLT. The patient recovered uneventfully. He will undergo scheduled adjuvant chemotherapy. Customized design for PV reconstruction using interposition vein graft with viable PV inflow source can result in successful PV reconstruction with complete removal of PVTT.