Teratoid Hepatoblastoma With Yolk Sac-Like and Neuroendocrine Elements.

Teratoid hepatoblastoma (HB) is a variant of mixed HB described as having a mixture of heterologous components. A 3-year-old boy presented for a liver transplant evaluation due to persistent HB. His liver was biopsied as well as a perirenal mass. Histologic examination demonstrated elements of yolk sac tumor and review of original resection showed a neuroendocrine component. This unique combination of histology has not been reported before in HB. Also, this case presents a unique diagnostic challenge as it presented with a metastasis containing yolk sac elements. Recognition and awareness of this histologic variant are important to accurately identify metastatic lesions.