As the name implies, these tumors arise from various “germ cells” found in the brain. They can be either benign or malignant. Germ cell tumors include the germinoma, the teratoma, the more aggressive embryonal carcinoma and yolk sac (endodermal sinus) tumors and the choriocarcinoma. Mixed germ cell tumors also exist. Because all these tumors tend to spread via the cerebrospinal fluid, diagnosis includes a check of the entire brain and spinal cord.
Germ cell tumors arise in the pineal or suprasellar regions of the brain.
Symptoms depend on the location of the tumor. Patients with tumors in the pineal region usually have headache and vision problems. Patients with tumors in the suprasellar region usually have hormone-related issues.
Because of their location, most germ cell tumors are treated with chemotherapy or a combination of radiation and chemotherapy rather than surgery. However, a biopsy to establish an exact diagnosis is not uncommon, and some very experienced surgeons have had success removing certain pineal region tumors. Surgery may be necessary to treat hydrocephalus (excess water in the brain) caused by a blockage, by the tumor, or the cerebrospinal fluid pathways.
These uncommon tumors represent 3-5% of childhood brain tumors and occur primarily in young people between the ages of 11 and 30.