Central nervous system germ cell tumors: controversies in diagnosis and treatment.

The variability and complexity of central nervous system germ cell tumors have led to controversy in both diagnosis and management. If a germ cell tumor is suspected, the measurement of cerebrospinal fluid and serum alpha-fetoprotein and beta-human chorionic gonadotropin is essential. A histologic specimen is not necessary if the patient has elevated levels; however, if the tumor markers are negative, a biopsy is needed to confirm the diagnosis of a germinoma. Germinomas are extremely radiosensitive, enabling 5-year survival rates that exceed 90%. Treatment has traditionally included focal and craniospinal axis irradiation; however, multiple ongoing studies are being conducted to examine the efficacy of reduction or elimination of radiation therapy with the addition of chemotherapy. Nongerminomatous germ cell tumors, on the other hand, are relatively radioresistant with a poorer outcome. The combination of chemotherapy and irradiation is associated with overall survival rates of up to 60%. This article provides a review of the controversies in diagnosis and treatment of central nervous system germ cell tumors.