Central nervous system (CNS)
germ cell tumors (GCTs) represent approximately 3% of primary pediatric
brain tumors and encompass a wide pathologic spectrum. CNS GCTs are most commonly located in the pineal and suprasellar regions of the brain and can be divided into major groups including
germinomas and nongerminomatous GCTs (NGGCTs), with
teratomas often considered a separate category. The clinical presentation varies by location and size, and it frequently includes endocrine abnormalities, visual changes, and signs of increased intracranial pressure. Neuroimaging studies cannot differentiate GCTs from other
tumors, and therefore, the diagnosis usually requires histologic confirmation. The rare exceptions are the cases where characteristic elevations of
tumor markers, including
alpha-fetoprotein and/or beta-
human chorionic gonadotropin are documented in the serum and/or cerebrospinal fluid. In these cases, the imaging findings along with the
tumor marker elevation may be diagnostic in themselves without the need for tissue confirmation. Treatment and prognosis differ greatly between groups.
Germinomas have a superior prognosis than NGGCTs. Five-year overall survival rates >90% were reported initially with the use of
craniospinal irradiation. More recently, the use of
chemotherapy in addition to
radiation therapy has afforded the ability to decrease the dose and volume of
radiation therapy without affecting survival rates. NGGCTs are less radiosensitive than
germinomas, but the use of
adjuvant chemotherapy has improved survival rates in this group as well. The standard management for CNS GCTs remains controversial. Treatment regimens aimed to improve progression-free and overall survival times are ongoing.