Malignant Liver Tumors in Children

Abstract

Age at presentation is often the key to the differential diagnosis of a liver mass in children. Hepatoblastoma is the most common malignant liver tumor in infants and toddlers, whereas hepatocellular carcinoma is seen in older children and adolescents. Although symptoms are possible, these tumors most often present as an asymptomatic epigastric or right upper quadrant mass. Definitive diagnosis is made with percutaneous, laparoscopic or open biopsy, and biopsy is recommended in all patients unless radiographic imaging clearly demonstrates a benign hemangioma. The most common benign tumors are infantile hemangioma, focal nodular hyperplasia and mesenchymal hamartoma. Hepatoblastoma is often chemosensitive and, if resectable, may have a good prognosis. Conversely, hepatocellular carcinoma is often chemoresistant and is frequently diagnosed at an advanced stage making resection difficult. The pretreatment extent of disease is a stratification system developed by the Society of Pediatric Oncology Liver Tumor Study Group (SIOPEL) that is now used worldwide to stratify risk and predict surgical resectability. Treatment protocols recommended by Children's Oncology Group and SIOPEL are reviewed. Other malignant tumors discussed briefly include sarcomas (rhabdomyosarcoma, angiosarcoma and undifferentiated or embryonal sarcoma), rhabdoid tumors and metastatic disease.