This group of brain tumors arise from sex cells and are related to various tumors of the sex organs. These cells are commonly called germ cells. These brain tumors tend to occur in young people, most are seen in patients under thirty years of age. The most common tumor in this group is the germinoma. Other members of the germ cell tumor classification are embryonal carcinoma, yolk sac tumor, choriocarcinoma and teratoma. These are all malignant tumors except for the teratoma. In male patients, the brain tumors tend to be located in the region of the pineal gland (in the middle back portion of the brain). In female patients, the brain tumors tend to be in the region of the pituitary gland (at the base of the skull near the front).
SYMPTOMS
The symptoms of a germ cell tumor are related to its location, size and speed of growth. A common feature is hydrocephalus (blockage of spinal fluid within the brain). This can cause headaches, nausea, vomiting and double vision. Brain tumors near the optic nerves can cause visual loss.
DIAGNOSIS
A careful history and physical examination is the first step in diagnosis. An MRI scan performed without and with intravenous contrast material is the best diagnostic test. Sometimes an MRI scan of the entire spine will also be performed. These tumors can secrete chemicals called markers into the spinal fluid. These include alpha-fetoprotein, placental alkaline phosphatase and human chorionic gonadotropin. These are usually used to monitor treatment rather than to make a diagnosis.
TREATMENT
These brain tumors are generally treated with radiation therapy and or chemotherapy. Frequently, however, surgery is necessary to biopsy the brain tumor. This allows an exact diagnosis.