A hypothalamic tumor is an abnormal growth in the hypothalamus gland, which is located in the brain.

The exact cause of hypothalamic tumors is not known. It is likely that they result from a combination of genetic and environmental factors.

In children, most hypothalamic tumors are gliomas. Gliomas are a common type of brain tumor that results from the abnormal growth of glial cells, which are a type of cells that support nerve cells. Gliomas can occur at any age, but they are often more aggressive in adults than children.

In adults, tumors in the hypothalamus are more likely to be metastatic (resulting from the spread of cancer from another organ to the hypothalamus) than they are when they occur in children.

People with neurofibromatosis (a hereditary condition) are at increased risk for this type of tumor in particular, and those who have undergone radiation therapy are at increased risk for developing tumors in general.

These tumors can cause a range of symptoms:

• Cachexia (loss of body fat and appetite)
• Euphoric "high" sensations
• Failure to thrive (lack of normal growth in children)
• Headache
• Hyperactivity

Such symptoms are most frequently seen in children whose tumors affect the anterior (front) portion of the hypothalamus.

Some tumors may extend to the visual pathways, which can cause loss of vision. If the tumors block the flow of spinal fluid, headaches and sleepiness may result from hydrocephalus (collection of fluid in the brain).

Some patients can have seizures as a result of brain tumors. Other patients may develop precocious puberty or elevated prolactin levels.

Your health care provider may identify an abnormal development during a regular checkup. He or she will perform a neurological exam, including testing of visual function. Blood tests for hormone imbalances may also be performed.

Depending on the results of the examination and blood tests, a CT scan or MRI scan can determine the presence of hypothalamic tumors.

Visual field testing may provide more information about how severely affected vision is and can help determine if the condition is improving or worsening.

The treatment depends on the aggressiveness of the tumor and whether it is a glioma or another type of cancer. Treatment options involve combinations of surgery, radiation, and chemotherapy.

Special radiation treatments can be focused on some tumors (gamma knife) and can be as effective as surgery but pose less risk to surrounding tissue. Brain swelling caused by a tumor may need to be treated with steroids.

Hypothalamic tumors may produce hormones or alter hormone production, leading to imbalances that may need to be corrected. In some cases, hormone replacement or suppression may be necessary.

There are nationwide and state support groups for patients with hypothalamic tumors and their families that may be found via an Internet search.

Prognosis depends on several factors:

• The specific type of tumor (that is, glioma or other type)
• Location of the tumor
• Grade of tumor
• Size of tumor
• Age and general health of the patient

In general, gliomas in adults are more aggressive than in children and usually indicate a worse outcome. Tumors causing hydrocephalus may cause additional complications, such as requirement for surgery.

Complications of brain surgery may include the following:

• Bleeding
  • Brain damage
  • Death (rarely)
• Infection

Seizures can result from the tumor or from any surgical procedure on the brain.

Hydrocephalus can occur with some tumors and can require surgery or a catheter placement in the brain to reduce spinal fluid pressure.

Risks of radiation therapy include damage to healthy brain cells along with destruction of the tumor cells.

Common side effects from chemotherapy include loss of appetite, nausea and vomiting, and fatigue.

Call your health care provider if you or your child develops any symptoms of a hypothalamic tumor. Regular medical check-ups may detect early signs of a problem, such as abnormal weight gain or abnormal puberty.

Molitch ME. Neuroendocrinology and the neuroendocrine system. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, PA: Saunders Elsevier; 2007:chap 241.