Congenital hepatoblastoma presenting with hepatic arteriovenous fistulas: a case report

Contemporary state-of-the-art management of cancer is increasingly defined by individualized treatment strategies. For very rare tumors, like hepatoblastoma, the development of biologic markers, and the identification of reliable prognostic risk factors for tailoring treatment, remains very challenging. The Children's Hepatic tumors International Collaboration (CHIC) is a novel international response to this challenge.

Hepatoblastomas (HBs) and pediatric hepatocellular carcinomas (HCCs) together account for almost 80% of primary malignant liver tumors in children and adolescents/young adults. Children’s Hepatic International Collaboration (CHIC), Children’s Oncology Group (COG), SociétéInternationale d’Oncologie Pédiatrique (SIOP), and International Childhood Liver Tumors Strategy Group trials have contributed to define prognostic factors and risk stratification in these tumors. The recently proposed histologic International Consensus classification of HB and HCC in children based on retrospective analysis from CHIC cases represents the base to define entities with homogeneous clinicopathologic and molecular features. This review will provide a morphologic guide for the upcoming International Liver Tumor treatment trial (Pediatric Hepatic International Tumour Trial) to be conducted through several continents. There will be an emphasis on molecular features and immunohistochemical markers for the definition of the individual histologic subtypes of HB and to better characterize the group of liver tumors in the provisional category of hepatocellular neoplasm—not otherwise specified. A brief overview of HCC in children will also be provided.