Hypothalamic and basal forebrain germinoma presenting with amnesia and hyperphagia.

Patients harboring primary intracranial germinomas usually have had Parinaud's syndrome and hydrocephalus (with pineal tumors) or hypopituitarism, visual loss, and diabetes insipidus (with suprasellar tumors) at presentation. The few reported cases of verified intraparenchymal hypothalamic germinomas all have been in prepubertal males with progressive neurologic deficits, altered levels of consciousness, or clinically apparent panhypopituitarism. The subject of this report was an endocrinologically normal, primiparous 24-year-old woman who presented with hydrocephalus followed by worsening anterograde amnesia and hyperphagia despite having a functioning ventriculoatrial shunt. Computed tomography scanning and magnetic resonance imaging demonstrated an anterior hypothalamic, thalamic, and basal forebrain mass, which stereotactic biopsy proved to be a germinoma. Intraaxial germinomas restricted to the anterior hypothalamus or thalamus rarely have been reported. The clinical features of the current patient may be unique.