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.

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.

Background: The 5th edition of WHO classification (WHO5) renamed pituitary adenoma as pituitary neuroendocrine tumor (PitNET), aligning with NET nomenclature from other sites.This study investigated the clinicopathological characteristics of surgically resected PitNET based on the WHO5 classification. Methods: A retrospective analysis was conducted on 210 cases of surgically resected and pathologically confirmed PitNET treated at Seoul National University Hospital from 2021 to 2023. The tumors were graded using the French five-tiered grading system proposed by Trouillas et al. Detailed information on grade 3 metastatic PitNET cases is provided. Results: The cohort’s median age was 53 years (age range: 8–84 years), with a male-to-female ratio of 1:1.1. Mean tumor size was 2.5 cm (range: 0.1–6.5 cm). Macroadenomas predominated (91.9%), followed by microadenoma (6.7%), and giant tumors (1.4%), with 56.2% extending suprasellarly. SF1-lineage PitNET was most prevalent (49.5%), followed by PIT1-lineage (23.3%) and TPIT-lineage (17.1%). Null cell tumors (5.7%) and unclassified plurihormonal PitNET (4.3%) were rare. PIT1-lineage PitNET comprised somatotrophs (47.0%), mature plurihormonal PIT1 lineage tumors (18.4%), thyrotrophs (16.3%), immature PIT1-lineage tumors (16.3%), and acidophilic stem cell tumors (n=1), however, there was no lactotroph PitNET. Among SF1-lineage tumors, serologically non-functional tumors predominated (79%), while, immunohistochemically, 71.2% were gonadotrophin (FSH/LH)-positive.Tumor grades by the French five-tiered classification system were distributed as follows:grade 1a (58.1%), 1b (17.6%), 2a (16.2%), 2b (7.1%), and 3 (1.0%). Two cases of metastatic corticotroph PitNET were observed: The first case, a 50-year-old female had liver metastasis and experienced tumor recurrence 7 years after his initial diagnosis of PitNET, ultimately dying 9.5 years later. The primary tumor appeared bland, but the metastatic tumor exhibited a high mitotic rate and a Ki-67 index was 48%. The second case involved a 44-year-old man with metastases to the paranasal sinus, liver, and bone. Despite showing initial bland histopathology and a low proliferation index, this tumor displayed aggressive behavior.The patient had a recurrence 1.5 years after diagnosis, with additional metastases emerging 3 years later. He survived for 8.0 years and is currently disease-free following surgery, chemotherapy, and radiotherapy. Conclusion This comprehensive analysis of surgically resected PitNETs using the new WHO5 classification provides valuable insights into the distribution of the subtypes in the surgical cohort. Key findings were the predominant gonadotroph PitNET, the absence of lactotroph PitNET, and the rarity of null cell tumors in surgical cases. The lack of lactotrophs was mainly due to medical treatment. This study highlights the discrepancy between serological and immunohistochemical findings of SF1-lineage PitNETs. While metastatic PitNET cases showed poor prognosis, the predictive value of the French grading system for PitNET requires further validation through extended follow-up.

Purpose: The purpose of this study was to determine the characteristics of patients with failed initial Kasai portoenterostomy (KP) and to compare the long-term prognosis of redo-KP with that of liver transplantation (LT) in these patients. Methods: The medical records of patients with biliary atresia (BA) who failed initial KP from 2010 to 2021 at a single center were retrospectively analyzed. KP failure was defined as persistent jaundice (total bilirubin concentration, ≥2.0 mg/dL) after KP or the performance of LT. Results: During the study period, 32 patients experienced initial KP failure, with 10 undergoing redo-KP and 22 undergoing LT. Redo-KP was successful in a minority of patients with failed initial KP, but the complications, particularly cholangitis, were more frequent in the redo-KP group. The long-term prognosis of redo-KP compared to LT showed that while some patients benefited from native liver survival after redo-KP, LT remains the more definitive solution for sustained liver function and survival in patients with BA. Conclusion The only factor differing significantly between patients who underwent redo-KP and LT after failed initial KP was complications of cholangitis. Redo-KP was successful in 4 of 10 patients with failed initial KP, suggesting that redo-KP may be a treatment option in patients with BA and failed initial KP.

Purpose: The purpose of this study was to determine the characteristics of patients with failed initial Kasai portoenterostomy (KP) and to compare the long-term prognosis of redo-KP with that of liver transplantation (LT) in these patients. Methods: The medical records of patients with biliary atresia (BA) who failed initial KP from 2010 to 2021 at a single center were retrospectively analyzed. KP failure was defined as persistent jaundice (total bilirubin concentration, ≥2.0 mg/dL) after KP or the performance of LT. Results: During the study period, 32 patients experienced initial KP failure, with 10 undergoing redo-KP and 22 undergoing LT. Redo-KP was successful in a minority of patients with failed initial KP, but the complications, particularly cholangitis, were more frequent in the redo-KP group. The long-term prognosis of redo-KP compared to LT showed that while some patients benefited from native liver survival after redo-KP, LT remains the more definitive solution for sustained liver function and survival in patients with BA. Conclusion The only factor differing significantly between patients who underwent redo-KP and LT after failed initial KP was complications of cholangitis. Redo-KP was successful in 4 of 10 patients with failed initial KP, suggesting that redo-KP may be a treatment option in patients with BA and failed initial KP.

Purpose: The purpose of this study was to determine the characteristics of patients with failed initial Kasai portoenterostomy (KP) and to compare the long-term prognosis of redo-KP with that of liver transplantation (LT) in these patients. Methods: The medical records of patients with biliary atresia (BA) who failed initial KP from 2010 to 2021 at a single center were retrospectively analyzed. KP failure was defined as persistent jaundice (total bilirubin concentration, ≥2.0 mg/dL) after KP or the performance of LT. Results: During the study period, 32 patients experienced initial KP failure, with 10 undergoing redo-KP and 22 undergoing LT. Redo-KP was successful in a minority of patients with failed initial KP, but the complications, particularly cholangitis, were more frequent in the redo-KP group. The long-term prognosis of redo-KP compared to LT showed that while some patients benefited from native liver survival after redo-KP, LT remains the more definitive solution for sustained liver function and survival in patients with BA. Conclusion The only factor differing significantly between patients who underwent redo-KP and LT after failed initial KP was complications of cholangitis. Redo-KP was successful in 4 of 10 patients with failed initial KP, suggesting that redo-KP may be a treatment option in patients with BA and failed initial KP.

Background: The 5th edition of WHO classification (WHO5) renamed pituitary adenoma as pituitary neuroendocrine tumor (PitNET), aligning with NET nomenclature from other sites.This study investigated the clinicopathological characteristics of surgically resected PitNET based on the WHO5 classification. Methods: A retrospective analysis was conducted on 210 cases of surgically resected and pathologically confirmed PitNET treated at Seoul National University Hospital from 2021 to 2023. The tumors were graded using the French five-tiered grading system proposed by Trouillas et al. Detailed information on grade 3 metastatic PitNET cases is provided. Results: The cohort’s median age was 53 years (age range: 8–84 years), with a male-to-female ratio of 1:1.1. Mean tumor size was 2.5 cm (range: 0.1–6.5 cm). Macroadenomas predominated (91.9%), followed by microadenoma (6.7%), and giant tumors (1.4%), with 56.2% extending suprasellarly. SF1-lineage PitNET was most prevalent (49.5%), followed by PIT1-lineage (23.3%) and TPIT-lineage (17.1%). Null cell tumors (5.7%) and unclassified plurihormonal PitNET (4.3%) were rare. PIT1-lineage PitNET comprised somatotrophs (47.0%), mature plurihormonal PIT1 lineage tumors (18.4%), thyrotrophs (16.3%), immature PIT1-lineage tumors (16.3%), and acidophilic stem cell tumors (n=1), however, there was no lactotroph PitNET. Among SF1-lineage tumors, serologically non-functional tumors predominated (79%), while, immunohistochemically, 71.2% were gonadotrophin (FSH/LH)-positive.Tumor grades by the French five-tiered classification system were distributed as follows:grade 1a (58.1%), 1b (17.6%), 2a (16.2%), 2b (7.1%), and 3 (1.0%). Two cases of metastatic corticotroph PitNET were observed: The first case, a 50-year-old female had liver metastasis and experienced tumor recurrence 7 years after his initial diagnosis of PitNET, ultimately dying 9.5 years later. The primary tumor appeared bland, but the metastatic tumor exhibited a high mitotic rate and a Ki-67 index was 48%. The second case involved a 44-year-old man with metastases to the paranasal sinus, liver, and bone. Despite showing initial bland histopathology and a low proliferation index, this tumor displayed aggressive behavior.The patient had a recurrence 1.5 years after diagnosis, with additional metastases emerging 3 years later. He survived for 8.0 years and is currently disease-free following surgery, chemotherapy, and radiotherapy. Conclusion This comprehensive analysis of surgically resected PitNETs using the new WHO5 classification provides valuable insights into the distribution of the subtypes in the surgical cohort. Key findings were the predominant gonadotroph PitNET, the absence of lactotroph PitNET, and the rarity of null cell tumors in surgical cases. The lack of lactotrophs was mainly due to medical treatment. This study highlights the discrepancy between serological and immunohistochemical findings of SF1-lineage PitNETs. While metastatic PitNET cases showed poor prognosis, the predictive value of the French grading system for PitNET requires further validation through extended follow-up.

Background: The 5th edition of WHO classification (WHO5) renamed pituitary adenoma as pituitary neuroendocrine tumor (PitNET), aligning with NET nomenclature from other sites.This study investigated the clinicopathological characteristics of surgically resected PitNET based on the WHO5 classification. Methods: A retrospective analysis was conducted on 210 cases of surgically resected and pathologically confirmed PitNET treated at Seoul National University Hospital from 2021 to 2023. The tumors were graded using the French five-tiered grading system proposed by Trouillas et al. Detailed information on grade 3 metastatic PitNET cases is provided. Results: The cohort’s median age was 53 years (age range: 8–84 years), with a male-to-female ratio of 1:1.1. Mean tumor size was 2.5 cm (range: 0.1–6.5 cm). Macroadenomas predominated (91.9%), followed by microadenoma (6.7%), and giant tumors (1.4%), with 56.2% extending suprasellarly. SF1-lineage PitNET was most prevalent (49.5%), followed by PIT1-lineage (23.3%) and TPIT-lineage (17.1%). Null cell tumors (5.7%) and unclassified plurihormonal PitNET (4.3%) were rare. PIT1-lineage PitNET comprised somatotrophs (47.0%), mature plurihormonal PIT1 lineage tumors (18.4%), thyrotrophs (16.3%), immature PIT1-lineage tumors (16.3%), and acidophilic stem cell tumors (n=1), however, there was no lactotroph PitNET. Among SF1-lineage tumors, serologically non-functional tumors predominated (79%), while, immunohistochemically, 71.2% were gonadotrophin (FSH/LH)-positive.Tumor grades by the French five-tiered classification system were distributed as follows:grade 1a (58.1%), 1b (17.6%), 2a (16.2%), 2b (7.1%), and 3 (1.0%). Two cases of metastatic corticotroph PitNET were observed: The first case, a 50-year-old female had liver metastasis and experienced tumor recurrence 7 years after his initial diagnosis of PitNET, ultimately dying 9.5 years later. The primary tumor appeared bland, but the metastatic tumor exhibited a high mitotic rate and a Ki-67 index was 48%. The second case involved a 44-year-old man with metastases to the paranasal sinus, liver, and bone. Despite showing initial bland histopathology and a low proliferation index, this tumor displayed aggressive behavior.The patient had a recurrence 1.5 years after diagnosis, with additional metastases emerging 3 years later. He survived for 8.0 years and is currently disease-free following surgery, chemotherapy, and radiotherapy. Conclusion This comprehensive analysis of surgically resected PitNETs using the new WHO5 classification provides valuable insights into the distribution of the subtypes in the surgical cohort. Key findings were the predominant gonadotroph PitNET, the absence of lactotroph PitNET, and the rarity of null cell tumors in surgical cases. The lack of lactotrophs was mainly due to medical treatment. This study highlights the discrepancy between serological and immunohistochemical findings of SF1-lineage PitNETs. While metastatic PitNET cases showed poor prognosis, the predictive value of the French grading system for PitNET requires further validation through extended follow-up.

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.

Background: The 5th edition of WHO classification (WHO5) renamed pituitary adenoma as pituitary neuroendocrine tumor (PitNET), aligning with NET nomenclature from other sites.This study investigated the clinicopathological characteristics of surgically resected PitNET based on the WHO5 classification. Methods: A retrospective analysis was conducted on 210 cases of surgically resected and pathologically confirmed PitNET treated at Seoul National University Hospital from 2021 to 2023. The tumors were graded using the French five-tiered grading system proposed by Trouillas et al. Detailed information on grade 3 metastatic PitNET cases is provided. Results: The cohort’s median age was 53 years (age range: 8–84 years), with a male-to-female ratio of 1:1.1. Mean tumor size was 2.5 cm (range: 0.1–6.5 cm). Macroadenomas predominated (91.9%), followed by microadenoma (6.7%), and giant tumors (1.4%), with 56.2% extending suprasellarly. SF1-lineage PitNET was most prevalent (49.5%), followed by PIT1-lineage (23.3%) and TPIT-lineage (17.1%). Null cell tumors (5.7%) and unclassified plurihormonal PitNET (4.3%) were rare. PIT1-lineage PitNET comprised somatotrophs (47.0%), mature plurihormonal PIT1 lineage tumors (18.4%), thyrotrophs (16.3%), immature PIT1-lineage tumors (16.3%), and acidophilic stem cell tumors (n=1), however, there was no lactotroph PitNET. Among SF1-lineage tumors, serologically non-functional tumors predominated (79%), while, immunohistochemically, 71.2% were gonadotrophin (FSH/LH)-positive.Tumor grades by the French five-tiered classification system were distributed as follows:grade 1a (58.1%), 1b (17.6%), 2a (16.2%), 2b (7.1%), and 3 (1.0%). Two cases of metastatic corticotroph PitNET were observed: The first case, a 50-year-old female had liver metastasis and experienced tumor recurrence 7 years after his initial diagnosis of PitNET, ultimately dying 9.5 years later. The primary tumor appeared bland, but the metastatic tumor exhibited a high mitotic rate and a Ki-67 index was 48%. The second case involved a 44-year-old man with metastases to the paranasal sinus, liver, and bone. Despite showing initial bland histopathology and a low proliferation index, this tumor displayed aggressive behavior.The patient had a recurrence 1.5 years after diagnosis, with additional metastases emerging 3 years later. He survived for 8.0 years and is currently disease-free following surgery, chemotherapy, and radiotherapy. Conclusion This comprehensive analysis of surgically resected PitNETs using the new WHO5 classification provides valuable insights into the distribution of the subtypes in the surgical cohort. Key findings were the predominant gonadotroph PitNET, the absence of lactotroph PitNET, and the rarity of null cell tumors in surgical cases. The lack of lactotrophs was mainly due to medical treatment. This study highlights the discrepancy between serological and immunohistochemical findings of SF1-lineage PitNETs. While metastatic PitNET cases showed poor prognosis, the predictive value of the French grading system for PitNET requires further validation through extended follow-up.