A craniopharyngioma is a rare, slow-growing, benign (non-cancerous) brain tumor. It begins growing near, but not inside, the pituitary gland. The pituitary gland is beneath the center of the brain, behind and between the eyes. This gland produces hormones that control many body functions.

Craniopharyngiomas can be large, fluid-filled cysts, solid cysts or a combination of each. They can occur in people of all ages. They are most common in children ages 5-14 and older adults. Each year, about two in every 1 million people are diagnosed with a craniopharyngioma.

Craniopharyngioma versus Pituitary Adenoma

Pituitary adenomas and craniopharyngiomas occur in the same general area of the brain. However, pituitary tumors begin from cells within the pituitary gland itself. Craniopharyngiomas develop outside the pituitary gland.

Craniopharyngioma Causes

Craniopharyngiomas occur when embryonic ectodermal cells get trapped near the pituitary gland when a baby is developing in the womb. Experts don’t know why some people develop these tumors and others do not.

Craniopharyngioma Symptoms

Craniopharyngiomas grow slowly. As they get bigger, they can put pressure on nearby tissue and affect the pituitary gland and other brain structures. They can affect cranial nerves (which are responsible for vision) and the endocrine system (which controls the body’s hormonal function). Symptoms can include:

  • Balance problems or trouble walking
  • Endocrine problems
  • Headaches
  • Nausea and vomiting
  • Vision problems, such as double vision or a narrow field of vision

Commonly, children with a craniopharyngioma have abnormally low levels of some hormones. This can lead to symptoms such as:

  • Delayed growth or short stature (short in height)
  • Delayed puberty
  • Excessive thirst and urination
  • Fatigue (extreme tiredness)
  • Personality or behavioral changes
  • Weight gain

Craniopharyngioma Diagnosis

If your child has or may have a craniopharyngioma, the next step is to see a pediatric neurosurgeon. This doctor will:

  • Do a physical and neurological exam to test your child’s vision, balance, coordination and reflexes. They will look at their growth and development.
  • Order blood tests to evaluate hormonal levels
  • Order imaging tests such as a computed tomography (CT) scan, magnetic resonance imaging (MRI) or both.

Adamantinomatous versus Papillary Craniopharyngiomas

There are two types of craniopharyngiomas:

  • Adamantinomatous craniopharyngiomas are the most common type. They can occur in children and adults. They develop from cells in a brain structure known as the craniopharyngeal duct.
  • Papillary craniopharyngiomas typically do not occur in children.

Craniopharyngioma Treatment

Treatment typically begins with surgery to remove all of the tumor or as much of it as possible. Depending on the size and location of the tumor, the neurosurgeon will use an open approach (craniotomy) or an endoscopic endonasal approach.

  • A craniotomy involves opening the skull to reach the tumor.
  • The endoscopic endonasal approach involves operating through the nose rather than through large incisions. The neurosurgeon puts tiny surgical tools into an endoscope in the nose. They are used to remove as much of the tumor as possible. Advanced imaging helps the neurosurgeon see the tumor and brain structures during surgery.

Craniopharyngiomas often occur near delicate brain structures, such as the optic nerve. The optic nerve is a cranial nerve that sends visual information from the eye to the brain. To protect these delicate structures, the neurosurgeon may not be able to remove all of the tumor.

After surgery, the neurosurgeon may recommend radiation therapy to shrink the rest of the tumor and prevent it from coming back.

Typically, removing all or some of the craniopharyngioma relieves symptoms. However, some damage caused by the craniopharyngioma may remain. This damage may include vision and endocrine problems.

Craniopharyngioma Prognosis

Even with expert care, the craniopharyngioma may never completely go away. Or it may go away at first and slowly grow back. Lifelong hormone medication can help. People diagnosed with craniopharyngioma need long-term follow-up care to ensure the tumor is not growing.