An unusual case of primary central nervous system germinoma with meningeal dissemination.

PURPOSE: Central nervous system germinomas often extend or disseminate into the ventricular and subarachnoid space. We present a case of primary central nervous system germinoma consisting mainly of meningeal dissemination, which is extremely unusual. CASE REPORT: A 16-year-old boy presented with pure germinoma, manifesting as anorexia and headache for 10 days. Radiological examinations revealed a large mass lesion in the posterior fossa and a small mass lesion on the pineal lobule with thickening of the tentorium cerebelli and falx. The patient underwent partial removal of the infratentorial tumor via open surgery. Intraoperative findings indicated extension of the dural and supracerebellar mass lesions into the epiarachnoid space. Three chemotherapy courses comprising ifosfamide, etoposide, and cisplatin were administered after the surgery. Craniospinal irradiation was administered subsequently. The adjuvant therapy had a complete response.
CONCLUSION: Central nervous system germinoma cells may have similar compatibility to meningeal components as they do to cerebrospinal fluid or the ventricular system. If there is a possibility of the tumor extending into the subdural space during surgical intervention or other events, a range of postdiagnostic irradiation should be considered to cover a wider range.