Abstract
A primary endodermal sinus (yolk sac) tumor of the liver occurring in an 18-month-old boy is described. Although several examples of extragonadal endodermal sinus tumors have occurred in other sites, this is believed to be the first reported instance of origin in the liver. An additional important feature was the detection of alpha-fetoprotein in a preoperative serum sample. Although no metastases were identified at the time of celiotomy, widespread metastases developed, and he died 6½ months after an extended right hepatectomy was performed. Neither triple chemotherapy nor radiation therapy appeared to deter progressive spread of the neoplasm, although the metastases exhibited some radiosensitivity.