Overview of Craniopharyngioma

A craniopharyngioma is a rare type of brain tumor, affecting one out of every 500,000 to 2,000,000 people per year. These tumors are usually benign (not aggressive), and there have been only a few cases of malignant (invasive) craniopharyngiomas reported.

Craniopharyngioma typically affects children between the ages of 5 and 14. Adults between the ages of 50 and 74 can develop these tumors as well. This tumor grows deep in the brain, close to the nasal passages. Children and adults can experience vision changes, headaches, and hormone problems as the result of a craniopharyngioma.

While the tumor can be surgically resected, chemotherapy and radiation may be needed to completely remove it. The prognosis is generally good. In children, survival rates range from 83 to 96% at five years after treatment, 65 to 100% at 10 years after treatment, and an average of 62% at 20 years after treatment. In adults, the overall survival rates range from 54 to 96% at five years, from 40 to 93% at 10 years and from 66 to 85% at 20 years.

Long-term complications can occur because the tumor is located in such a crucial region of the brain.

Location

This type of tumor grows in the sella turcica, near two small but significant parts in the brain—the pituitary gland and the optic chiasm.

The sella turcica is a bony structure in the brain where the pituitary gland is located. Your pituitary gland is a small endocrine gland that is responsible for regulating important physical functions including metabolism, growth, and maintenance of fluid and minerals in the body.

The optic chiasm, located right above the pituitary gland, is a major pathway where all of your visual nerve fibers meet.

As the tumor enlarges, it can produce pressure throughout the brain. It can also interfere with the flow of cerebrospinal fluid (CSF), potentially causing hydrocephalus (a buildup of fluid within the skull).

Symptoms

A craniopharyngioma typically grows slowly. The symptoms, which develop due to the tumor’s location within the brain, are usually subtle and gradual.

Headaches

Head pain is the most common symptom of craniopharyngioma and it can begin as the result of hydrocephalus or as the tumor takes on space in the brain. The headaches may be associated with a sensation of pressure, and changing your head position can improve or worsen the headaches.

Nausea and Vomiting

Other symptoms of craniopharyngioma may be that you experience nausea and vomiting after eating. You may also experience nausea and vomiting even when you haven’t had much to eat.

Fatigue and Hypersomnia

These symptoms may occur as a result of the tumor taking up space in the brain. Pressure on the pituitary gland—causing endocrine problems related to sleep and energy levels—can contribute as well.

Bitemporal Hemianopia

The tumor may press right in the center of the optic chiasm, which is the area of your nerves that sense peripheral vision in both of your eyes. If the tumor is a bit off-center, you may lose peripheral vision in only one eye.

Sometimes, the loss of peripheral vision begins in one eye and then involves both eyes as the tumor grows.

Frequent Urination and Excessive Thirst

Diabetes insipidus is a type of diabetes characterized by polyuria (frequent urination) and polydipsia (frequency thirst and drinking). This is caused by a deficiency in antidiuretic hormone (ADH), a hormone released by the pituitary gland.

ADH regulates the fluid in your body by keeping fluid in your body. When you don’t make enough ADH, you lose fluid through the urine. This makes you feel constantly thirsty as your body needs to compensate for that fluid loss.

Delayed Growth and Puberty

The pituitary gland secretes six hormones including growth hormone (GH), which regulates growth throughout life, especially during childhood and adolescence. Several hormones secreted by the pituitary gland regulate sexual maturation.

A craniopharyngioma can encroach on the pituitary gland, interfering with the release of some or all of these hormones, resulting in short stature and delayed or incomplete puberty.

Hypothyroidism

The pituitary gland secretes thyroid-stimulating hormone (TSH), which stimulates the thyroid gland. When this hormone is deficient, hypothyroidism results. Symptoms can include weight gain, low energy, irritability, depression, and sometimes cognitive delay.

Adrenal Insufficiency

Another hormone released by the pituitary gland, adrenocorticotrophic hormone (ACTH), stimulates the adrenal glands. When this hormone is deficient, symptoms can include alterations in blood sugar, blood pressure, and altered heart rate.

Causes

It's not clear why some people develop a craniopharyngioma, and there are no known risk factors or methods of prevention.

Diagnosis

If you have symptoms of craniopharyngioma, your medical evaluation may include some tests to help identify the cause of your problems.

Physical Examination

In addition to listening to your symptoms, your healthcare provider will do a physical examination. Depending on the size of the tumor, you may have some signs of craniopharyngioma on your physical examination even before you start to complain of symptoms.

Signs that may lead a healthcare provider to diagnose craniopharyngioma include:

• Temporal hemianopia (loss of peripheral vision in one or both eyes)
• Papilledema (swelling of one or both of your optic nerves—this can be detected with a special non-invasive eye exam that uses an ophthalmoscope)
• Altered blood pressure or heart rate as a result of adrenal insufficiency
• Dehydration from diabetes insipidus
• Growth problems
• Being underweight or overweight (depending on which hormones are affected)

Based on a combination of your symptoms and the signs on your physical examination, your healthcare provider may order additional tests.

Urinalysis (UA)

If you complain of frequent urination, a urinalysis can identify common causes such as a bladder infection and diabetes mellitus. With diabetes insipidus, the UA may detect dilute urine, which can be less than less than 200 milliosmoles (mOsm/kg)—this measurement indicates the concentration of solids that are present after dissolved in a fluid.

Keep in mind that a craniopharyngioma can, but does not always, cause diabetes insipidus.

Blood Tests

You may need to have your blood sugar and electrolyte levels checked, particularly if you have signs of adrenal insufficiency or diabetes insipidus. If your child has slow growth, your healthcare provider may order thyroid tests as well as tests for other hormone levels, including growth hormone.

Brain Imaging

If you or your child has headaches, vision changes, or signs of swelling of the brain (such as papilledema), your healthcare provider may order a brain computerized tomography (CT) or magnetic resonance imaging (MRI). If a craniopharyngioma is present, the imaging examination may show a tumor in or near the sella turcica. Brain imaging may show hydrocephalus as well.

Often, it is a progression of symptoms that trigger a diagnosis, particularly because the symptoms and signs are not dramatic when the tumor is small.

Treatment

Surgical resection of the tumor is generally the preferred treatment for craniopharyngioma. Of course, each situation is unique, and you may not be able to have surgery due to the location of your tumor or other health issues.

Often, full treatment involves a combination of surgery and other treatment such as radiation and chemotherapy. Management of endocrine issues before and after surgery is an important aspect of the treatment of your craniopharyngioma as well.

There are several surgical approaches used to remove craniopharyngioma. Your healthcare provider will select the safest and most effective approach based on the size and characteristics of your tumor. The approaches include:

• Transcranial: When your healthcare provider must access the tumor through the skull
• Transseptal transsphenoidal: The approach used when your healthcare provider removes your tumor through the bones above your nasal passages
• Endoscopic endonasal: When incisions are not made, and the tumor is removed through a tube that is placed through your nostrils and threaded through the sella, where the tumor is located

If your tumor cannot be completely removed because it is located too close to the pituitary gland, optic chiasm, or hypothalamus (a hormone control region in the brain), then you may need to have additional treatment with radiation or chemotherapy to completely eradicate it.

Prognosis

After a craniopharyngioma is removed, additional care may be necessary for several reasons.

Sometimes, endocrine problems persist, including obesity and metabolic syndrome. This can occur as a result of tumor growth into the pituitary gland or hypothalamus or as a complication of surgical or radiation treatment.

In these situations, you may need long-term management with hormone replacement. Additionally, you may need to take medication to help maintain optimal blood sugar or blood pressure.

A Word From Verywell

If you, your child, or a loved one develops a craniopharyngioma, you may be alarmed to hear that this is a brain tumor. You should be assured that this tumor does not spread to invade other regions of the brain, and it is not considered a fatal brain tumor. Nevertheless, lifelong treatment may be necessary to manage the complications that can occur if the tumor or its treatment causes disruption of nearby endocrine or visual structures.