Other brain tumors
There are a number of different brain tumors that do not begin in glial tissue.
- Meningiomas (also called meningeal tumors) grow from the meninges, which are the three thin membranes that surround the brain and spinal cord. These tumors are usually benign (non-cancerous). Because these tumors tend to grow very slowly, the brain may be able to adjust to their presence. Meningiomas frequently grow quite large before they cause symptoms. This type of brain cancer occurs most often in women ages 30 to 50.
- Pituitary tumors develop from the pituitary gland. Most pituitary tumors are benign. They are divided by size into macroadenomas (greater than 1 cm in size) and microadenomas (less than 1 cm in size). Arising from the pituitary gland (master gland of the body), these tumors can over-produce a variety of hormones. This overproduction of hormones typically causes symptoms, such as fatigue, menstrual irregularities, and weight gain or loss, among many others. Most pituitary tumors, however, do not produce hormones. These tumors, which are common among 30-50 year olds, can still create problems when they become large enough to push on the nearby optic nerves.
- Craniopharyngiomas develop in the area of the brain near the pituitary gland (the main endocrine gland which produces hormones that control other glands and many body functions, especially growth) near the hypothalamus. These brain tumors are usually benign. However, they may sometimes be considered malignant because they may create pressure on, or damage, the hypothalamus and affect vital functions (such as body temperature, hunger and thirst). These tumors occur most often in children and adolescents, or adults over age 50.
- Germ cell tumors arise from developing sex (egg or sperm) cells, also known as germ cells. The most common type of germ cell tumor in the brain is the germinoma. Aside from the brain, germinomas can form in the ovaries, testicles, chest and abdomen. Most germ cell tumors occur in children.
- Pineal region tumors occur in or around the pineal gland, a small organ located in the center of the brain. The pineal gland produces melatonin, a hormone that plays an important role in the sleep-wake cycle. These brain cancer tumors can be slow growing (pineocytoma) or fast growing (pineoblastoma). Since the pineal region is very difficult to reach, it requires a high level of surgical expertise to remove these tumors.
- Medulloblastomas are fast-growing brain tumors that develop from the neurons of the cerebellum. The cerebellum is the lower back of the brain and controls movement, balance and posture. These tumors are usually found in children or young adults.
- Primary CNS lymphomas develop in lymph tissue of the brain or spinal cord. This type of brain tumor is usually found in people whose immune systems are compromised.