Suprasellar malignant mixed germ cell tumour presenting as craniopharyngioma.

A 15 year old boy presented with diminution in vision of both eyes, diabetes insipidus and hypopituitarism. MRI was suggestive of a large suprasellar and retrosellar craniopharyngioma with stretching of the optic chiasma. Histopathological findings on the first surgical specimen were interpreted as a craniopharyngioma. He was reoperated on account of clinical deterioration and increase in tumour size. Histological examination this time revealed derivatives of all three germ cell lineages along with areas of embryonal carcinoma, and yolk sac tumour besides squamous cysts, establishing the diagnosis of malignant mixed germ cell tumour. Serum and CSF were strongly positive for alpha foetoproteins.