Diencephalic syndrome of emaciation (Russell's syndrome).

Diencephalic syndrome of emaciation (Russell's syndrome) characteristically presents with the symptoms of marked emaciation in spite of normal linear growth and marked increased of serum growth hormone in infancy and early childhood. It is usually caused by a low-grade glioma, most often an astrocytoma, of the anterior third ventricle including the optic nerve and chiasm. Usually it is not associated with von Recklinghausen's neurofibromatosis. We describe two unusual cases of diencephalic syndrome; one case was caused by a low-grade astrocytoma involving the anterior third ventricle associated with neurofibromatosis, and the other by a malignant astrocytoma of the anterior third ventricle.