Perinatal (fetal and neonatal) germ cell tumors.

BACKGROUND/PURPOSE: Germ cell tumors are relatively common in the fetus and neonate and are the leading neoplasms in some perinatal reviews. The purpose of this study is to focus on the fetus and neonate in an attempt to determine the various ways germ cell tumors differ clinically and morphologically from those occurring in the older child and adult and to show that certain types of tumors have a better prognosis than others.

METHODS: The author conducted a retrospective review of perinatal teratomas and other germ cell tumors reported in the literature and of patients treated and followed up at Children's Hospital San Diego and Children's Hospital Los Angeles. Only fetuses and infants less than 2 months of age with adequate clinical and pathologic data were accepted for review.

RESULTS: Five hundred thirty-four fetuses and neonates presented with teratomas diagnosed prenatally (n = 226) and at birth (n = 309). The most common initial finding was a mass, noted either by antenatal sonography or by physical examination during the neonatal period, with signs and symptoms referable to the site of origin. Overall polyhydramnios was next followed by respiratory distress and stillbirth. The number of mature and immature teratomas was approximately the same. The incidence of teratoma with yolk sac tumor either at presentation or at recurrence was 5.8%, and the survival rate was 39%. Sacrococcygeal teratomas had the highest incidence of yolk sac tumor at 10%. Recurrent disease in the form of either teratoma or yolk sac tumor developed in 5% of patients. All individuals with teratomas who survived received surgical resection.

CONCLUSIONS: Some germ cell tumors of the fetus and neonate have a better prognosis than others. Neonates with gastric teratomas have the best survival rates, and those with intracranial germ cell tumors the worst. Fetuses with teratomas detected antenatally have 3 times the mortality rate compared with postnatally diagnosed neonates. Although perinatal teratomas have a relatively low recurrence rate of 5%, close follow-up with imaging studies and serum alpha-fetoprotein determinations is is strongly recommended. Surgical resection alone may be adequate therapy for teratomas with nonmetastatic, microscopic foci of yolk sac tumor. In the nonteratoma group, patients with pure yolk sac tumor and gonadoblastoma have a much better outcome than those with choriocarcinoma, which has a very low survival of rate of 12%. Currently, the use of platinum-based combination chemotherapy has significantly improved the survival rate of infants with advanced malignant germ cell tumor disease.