Definition and Overview
Craniopharyngioma is a rare, localised, and slow-growing tumor that begins in the cells along the base of the brain near the pituitary gland. The pituitary gland is responsible for regulating many hormones and is connected to the hypothalamus. Right above it are the optic nerves that connect the eyes to the brain.
The tumor is more common in children than adults with most patients being diagnosed between the ages of five and 14. Adult patients, on the other hand, are typically diagnosed over the age of 45.
Craniopharyngioma, just like meningioma, is a benign tumor (non-cancerous) but it can grow to a large size causing increased pressure on the optic tract and pituitary gland. When this happens, symptoms ranging from dry skin to vision loss, begin to develop. The tumor does not usually spread to other organs but can develop to some of the brain’s most important structures and cause changes in hormone levels. Just like other types of brain tumors, such as glioblastoma, it is also very aggressive. It can cause serious damage to the optic chiasm and hypothalamic areas. Its standard treatment remains to be transsphenoidal or transcranial surgery followed by post-surgical radiotherapy. Despite high cure rate, the condition is still associated with multisystem morbidity. Visual field defects and pituitary insufficiencies persist in some patients who have undergone surgery.
Cases of craniopharyngioma are very rare with only 120 patients diagnosed in the United States every year.
Causes of Condition
Just like other types of brain cancer, the exact causes of craniopharyngioma remain unknown. What is known, however, is that it commonly affects children between five to ten years of age. It has also been established that the condition does not “run in families” or inherited from the parents.
Patients with craniopharyngioma experience different brain tumor symptoms depending on the location of the abnormal growth and the specific hormones it affects. These symptoms include:
Behavioral and learning problems
Excessive thirst and urination
Hydrocephalus (when the tumor blocks the normal flow of cerebrospinal fluid)
Increased pressure on the brain
Pituitary insufficiency resulting in delayed puberty and growth failure
Vision problems due to damage or pressure to the optic nerve
If the tumor affects the hypothalamus, patients can also develop diabetes insipidus and suffer from increased drowsiness, obesity, and temperature regulation abnormalities.
Who to See and Types of Treatments Available
Parents of children who experience the symptoms mentioned above are advised to seek medical attention as soon as possible. If the tumor is found and removed while it is still small, the prognosis is generally good.
Craniopharyngioma is diagnosed with high-resolution computed tomography (CT) or magnetic resonance imaging (MRI) scan of the brain. These imaging tests allow neuroradiologists to assess the tumor from different angles. Pituitary function testing may also be performed.
Treatment of craniopharyngioma follows the same protocols as treatment of other types of tumors and cancers including lymphoma, pancreatic cancer, leukemia, and multiple myeloma. It requires the skills and expertise of a team of specialists from many disciplines. The primary treatment method is surgery for the removal of the tumor and decompression of the optic chiasm. The procedure can be performed using minimally invasive endoscopic endonasal approach wherein instead of a head incision, the surgeon utilizes the patient’s natural passageway. This complex procedure is performed by neurosurgeons with advanced and extensive experience.
In some cases, an open craniotomy is warranted in which an incision is made in the patient’s scalp to access and remove the tumor.
Both surgical methods can cause complications that can result in complete pituitary insufficiency. When this happens, the patient will require lifelong hormone replacement therapy. Patients also face the risk of damage to the hypothalamus, developing diabetes insipidus, and optic nerve damage that can lead to blindness.
In cases wherein the tumor cannot be completely removed, radiation therapy is used.
Patients who have undergone treatment for craniopharyngioma have up to 90% chance of cure as long as the tumor is completely removed. However, there is a chance of recurrence, which usually occurs within the first two years after surgery.
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