Recurrent intracranial germinoma outside the initial radiation field with progressive malignant transformation.

A 19-year-old man with a pure germinoma in the pineal region was successfully treated with chemotherapy followed by 24 Gy local irradiation. Eight months later, magnetic resonance (MR) imaging detected ventricular wall dissemination outside the radiation field. Near complete response was achieved again after 28.8 Gy whole brain and 24 Gy whole spine irradiation. Two months later, MR imaging demonstrated recurrence of a mass at the corpus callosum. Gamma knife radiosurgery did not control this mass, so tumour resection was performed. Histological examination revealed immature teratoma. Enlargement of the recurrent mass at the trigone of the left lateral ventricle was found in spite of additional chemotherapy. Tumour extirpation was performed and histological examination revealed embryonal carcinoma. The patient died of tumour progression 34 months after the initial treatment. By a combination of chemotherapy regiments in use today, the initial radiation field to treat intracranial germinomas should not be confined to the tumour bed.