Hepatoblastoma
Hepatoblastoma is a malignant liver cancer occurring in infants and children and composed of tissue resembling fetal liver cells, mature liver cells, or bile duct cells. They usually present with an abdominal mass. The disease is most commonly diagnosed during a child's first three years of life. Alpha-fetoprotein levels are commonly elevated, but when AFP is not elevated at diagnosis the prognosis is poor.
Signs and symptoms
Patients are usually asymptomatic at diagnosis. As a result, disease is often advanced at diagnosis.Pathophysiology
Hepatoblastomas originate from immature liver precursor cells, are typically unifocal, affect the right lobe of the liver more often than the left lobe, and can metastasize. They are categorized into two types: "Epithelial Type" and "Mixed Epithelial / Mesenchymal Type."Individuals with familial adenomatous polyposis, a syndrome of early-onset colonic polyps and adenocarcinoma, frequently develop hepatoblastomas. Also, beta-catenin mutations have been shown to be common in sporadic hepatoblastomas, occurring in as many as 67% of patients.
Recently, other components of the Wnt signaling pathway have also demonstrated a likely role in constitutive activation of this pathway in the causation of hepatoblastoma. Accumulating evidence suggests that hepatoblastoma is derived from a pluripotent stem cell.
Syndromes with an increased incidence of hepatoblastoma include Beckwith–Wiedemann syndrome, Edward Syndrome, Down Syndrome, Aicardi syndrome, Li–Fraumeni syndrome, Goldenhar syndrome, von Gierke disease, and familial adenomatous polyposis.