[Germ-cell tumors of the central nervous system in childhood: retrospective study of 13 patients].

BACKGROUND AND PURPOSE: Germ cell tumors (GCT) of the central nervous system are rare (2% of all brain tumors in children). Although originating from germ cells, GCT cover a spectrum of different tumors with different management and prognosis, depending on whether they secrete tumor markers or not. The aim of this study is to present a series of children with GCT and comment on overall management practices.

METHODS: We retrospectively reviewed 13 children under the age of 18 years (nine boys and four girls), treated in the same institution between 1986 and 2006 for one or more primitive GCT of the central nervous system.

RESULTS: Median age at diagnosis is 12.9 years (7-17 years). Tumor markers (alpha foetoprotein [alphaFP], human chorionic gonadotrophin [betaHCG]) were assessed 11 times in blood as well as cerebrospinal fluid (CSF). Tumors were located as follows: pineal region (10 cases), hypothalamus (eight cases), basal ganglia (one case) and corpus callosum (one case). Six were bifocal (pineal region and hypothalamus). Clinical signs were mostly dominated by diabetes insipidus and intracranial hypertension. Seven children required surgery for hydrocephalus. Tumor markers were positive in three cases and these children subsequently received chemotherapy followed by radiotherapy, except one child. Eventually, the three patients with positive markers required surgery because of a residual lesion. The eight other patients had a stereotactic biopsy for diagnosis. At the end of follow-up, treatment morbidity appears to be low and neither death nor recurrence was observed. Mean follow-up is 8.85 years (2-20 years).

CONCLUSIONS: The prognosis of cerebral GCTs in children is excellent because of their pronounced chemo- and radiosensitivity. Surgery is crucial for diagnosis in the event of negative markers, or if there is evidence of residual tumor with normalization of tumor markers at the end of chemotherapy. Tumor markers must be monitored to check the diagnosis and for follow-up. The place of tumor biopsy during endoscopic third ventriculostomy (performed if hydrocephalus is present) is still debated.