What is a craniopharyngioma?
A craniopharyngioma is a tumor of the brain that commonly affects children. It grows in the area of the pituitary gland and the nerves that relay vision from the eyes to the brain (optic nerves), and frequently grows up into the base of the brain. The tumors arise from cells that in the developing embryo had helped to form the normal pituitary gland. For reasons that are not understood, these cells begin to grow on their own, producing masses that often contain both solid tissue and fluid. In children, portions of the tumor frequently have calcium deposits. The fluid ("cystic") portions of the tumors can reach very large size, and occasionally extend into both sides of the brain.
How does the craniopharyngioma cause symptoms?
These tumors cause symptoms in three major ways. Some children will initially have difficulties with hormonal functions since these tumors grow in or above the pituitary gland and because the pituitary gland regulates virtually all of the hormones in the body; including growth rate and the functions of the thyroid, adrenal, steroid, and sex glands. Perhaps the most common manifestation of this hormone effect is a fall-off in a normal growth rate due to a lack of growth hormone.
A second form of clinical symptom is related to increased pressure within the brain. These tumors can grow up into the base of the brain, obstructing the chambers in the brain ("ventricles") through which the fluid in the brain ("CSF") circulates. This obstruction results in headache, nausea, and vomiting - all symptoms of the fluid and pressure building up inside the brain; a condition called hydrocephalus.
A third, and unfortunately fairly common presentation of these tumors, is a loss of vision. Because children rarely complain about slowly developing health problems and because these tumors are located near the base of the brain where the optic nerves are located, it is possible for these tumors to put gradually increasing pressure on the optic nerves which leads to severe vision loss in one or both eyes in the peripheral or central part of the visual field. Many children will be initially diagnosed when they fail a vision test at school or when it is suddenly noted by their parents that their vision is dramatically reduced.
In a personal series of patients treated at the Dana-Farber/Children's Hospital Cancer Center over the past decade, the majority of children had diagnosed when they had symptoms because of pressure within the brain and blockage of CSF circulation. A slightly smaller percentage had visual deterioration and the smallest group had endocrine changes.
My child has been diagnosed as having a possible craniopharyngioma; what diagnostic tests should be carried out?
When some children with large craniopharyngiomas are initially diagnosed, they may be quite ill with increased pressure in their brain and there really is not much time to do any special additional diagnostic testing. In this case, surgery must be carried out rapidly to reduce the brain pressure.
If time is available, however, there are some tests that are helpful to the treating physicians. We believe it is worthwhile to get a standard CT scan of the brain to determine the extent of the calcium build-up within the tumor. Calcium deposits, which are not seen well on MRI, often denote areas of the tumor that may be difficult to remove and knowing location of these areas can help the surgeon plan the operation more effectively. We like to obtain endocrinologic and ophthalmologic evaluations before the surgery, since baseline evaluations of both of these areas of body function can help to predict post-operative problems and suggest management strategies to the neurosurgeon, anesthesiologist and endocrinologist caring for the child.
Once the diagnosis has been made, what are the options for treatment of my child's tumor?
There continues to be a great deal of discussion among pediatric neurosurgeons throughout the world regarding the appropriate treatment for these tumors. The two most commonly used treatment options include complete excision of the tumor surgically or partial removal followed by radiation therapy.
There is no question that total removal of these tumors is perhaps the only way of guaranteeing their cure. Yet because of the nature of the tumors themselves, total removal may sometimes result in complications that affect the quality of life of the child following surgery. For example, the frequently intense scarring in the brain next to these tumors may make their removal difficult without injury to the adjacent brain. Because the brain centers near the tumor typically control not only hormonal function but also the control of appetite and emotions, any of these functions could be adversely affected if these centers are injured during an attempt at total removal of the tumor. In addition, these tumors are often quite adherent to arteries that supply blood to vital areas of the brain. If these arteries are injured during the removal of the tumor, the patient could suffer a stroke resulting in permanent paralysis or other severe neurologic deficit. The bleeding that occurs when large arteries at the base of the brain are torn may be very difficult to stop.
Therefore, we believe that the surgeon must have as much information as is practicable to obtain regarding the tumor's boundaries and be able to use the utmost clinical judgment when removing the tumor in order to avoid or minimize these potential complications. Despite the most careful planning and intraoperative technical expertise, however, inadvertent injury to these vital structures can still occur.
Radiation therapy is an important part of treatment strategy in many institutions.
Although these tumors are "benign," their growth can be frequently slowed or stopped by radiation therapy. Various types of radiation therapy can be employed to treat craniopharyngioma including the delivery of external beam radiation to the tumor volume or the instillation of isotopes such as radioactive phosphorus ("P32") or Yttrium directly within cystic portions of the tumor. When these treatments are employed, a skull opening must be made for either the placement of a semi-permanent tube into the cyst or to provide an avenue for the direct injection of the radioactive isotope into the cyst.
Why aren't all craniopharyngiomas treated with radiation therapy if it is effective against the tumor?
Many children who come to the hospital with a craniopharyngioma are often very sick with pressure symptoms or visual deficits. The radiation therapy does not work quickly enough to reduce these symptoms and surgery is often required emergently to deal with the pressure of the tumor and cyst. Once radiation therapy is given, it unfortunately does not have a guaranteed cure rate and it is still possible for tumors to regrow even years after initial treatment. The radiation treatment in addition has the potential for significant long term side effects - including effects on the child's learning skills, hormonal status, and blood circulation to the brain - all because of the late damaging effects of radiation therapy to the brain of a developing child.
There have been many recent advances in the technological delivery of radiation therapy, however, that may lessen the long-term likelihood of these complications. It is beyond the scope of this presentation to discuss radiation therapy and its complications in detail, but this is an issue that you should explore in detail with your child's physicians when treatment options are being reviewed. The patient's age, symptoms, preoperative hormonal status, and size and configuration of the tumor are among the many factors which need to be taken into consideration when tumor treatment is planned.
What treatment options do you usually recommend for children with craniopharyngiomas?
Almost always, we attempt to remove as much of the tumor as is safely possible and, hopefully, cure the patient by removing all of it. We have been able to do this in about 65% of our operated patients. In the vast majority of children with craniopharyngiomas, the tumors grow from the pituitary stalk region; meaning that the removal of the tumor invariably results in a full and complete pituitary hormonal deficit. These children, therefore, require life-long replacement with hormones and must remain under the care of an endocrinologist throughout their growth and development. Even if surgery is completely successful in removing the tumor, there is still a possibility that the tumor could regrow from small fragments of the tumor inadvertently left behind at the operation. Some children will require reoperation to remove these recurrences.
Surgery does not sound very pleasant, but the effects of the tumor if left untreated will result in similar hormonal deficits eventually and in most cases the risks of surgery are well worth the benefits of reducing the intracranial pressure, preserving vision, and achieving a long term cure. If cysts formed by the tumor are extremely large and complex, we may drain them either as part of the initial operation or as a separate procedure using a tube directed through a hole in the skull into the cyst. Very rarely, we will utilize certain chemotherapeutic agents such as Bleomycin to slow or stop cyst growth by injecting them directly into the cyst themselves. There is relatively limited experience with this technique in North America, but there are several centers developing more experience with this technique and we have used it in a few patients in our own hospital with varying success.
What is the length of follow-up that is needed for a child following surgery for a craniopharyngioma?
Our experience is that these children will need life-time follow-up. Although many hospitals and surgeons state their cure rate in terms of 5 or 10 year follow up, recurrences of this tumor can occur remote from surgery. In a personal series, there has been a recurrence rate of 16% even after total removal as judged by post-operative scans and the surgeon's judgment at the initial operation. For this reason, we will follow our patients yearly until ten years after surgery and then on an every two year basis indefinitely.
The follow-up issues include not only the possibility of tumor regrowth, but also continued monitoring and treatment of side-effects related to radiotherapy and other adjuvant treatments. Most of our children with craniopharyngiomas are followed in the Pediatric Brain Tumor Clinic because in this clinic a continuing, ongoing relationship can be maintained with all of the specialists needed for long term follow-up including ophthalmologists, endocrinologists, neuropsychologists, neurologists, and neurosurgeons.
My surgeon has recommended focused radiation treatment (stereotactic radiosurgery, Gamma Knife, proton beam) for my child's tumor; is this recommendation reasonable?
For some patients, these highly focused, single-dose radiation techniques are a useful method to treat areas of tumor that cannot be successfully removed by any other means. Because these radiation modalities are intended to destroy all tissue that has been targeted, the technique is best used only for small tumor areas that are not touching structures whose function would be harmed by this type of radiation. For example, if the tumor is near or touching the brain stem or optic nerves, these treatments may not be safe. Prior radiotherapy also will affect radiation dose that can be used.
Purpose of This PDQ Summary
This PDQ cancer information summary for health professionals provides comprehensive, peer-reviewed, evidence-based information about the treatment of childhood craniopharyngioma. This summary is reviewed regularly and updated as necessary by the PDQ Pediatric Treatment Editorial Board.
Information about the following is included in this summary:
- Clinical presentation.
- Diagnostic evaluation.
- Histopathologic classification.
- Treatment options.
- Late effects.
This summary is intended as a resource to inform and assist clinicians and other health professionals who care for pediatric cancer patients. It does not provide formal guidelines or recommendations for making health care decisions.
Some of the reference citations in this summary are accompanied by a level-of-evidence designation. These designations are intended to help readers assess the strength of the evidence supporting the use of specific interventions or approaches. The PDQ Pediatric and Adult Treatment Editorial Boards use a formal evidence ranking system in developing their level-of-evidence designations. Based on the strength of the available evidence, treatment options are described as either “standard” or “under clinical evaluation.” These classifications should not be used as a basis for reimbursement determinations.
This summary is also available in a patient version, which is written in less technical language, and in Spanish.
The National Cancer Institute provides the PDQ pediatric cancer treatment information summaries as a public service to increase the availability of evidence-based cancer information to health professionals, patients, and the public. The PDQ childhood brain tumor treatment summaries are organized primarily according to the 2000 World Health Organization classification of nervous system tumors.
In recent decades, dramatic improvements in survival have been achieved for children and adolescents with cancer. Childhood and adolescent cancer survivors require close follow-up because cancer therapy side effects may persist or develop months or years after treatment. (Refer to the PDQ summary on Late Effects of Treatment for Childhood Cancer for specific information about the incidence, type, and monitoring of late effects in childhood and adolescent cancer survivors.)
Primary brain tumors are a diverse group of diseases that together constitute the most common solid tumor of childhood. Brain tumors are classified according to histology, but tumor location and extent of spread are important factors that affect treatment and prognosis. Immunohistochemical analysis, cytogenetic and molecular genetic findings, and measures of mitotic activity are increasingly used in tumor diagnosis and classification. (Refer to the PDQ summary on Childhood Brain and Spinal Cord Tumors Overview for information about the general classification of childhood brain and spinal cord tumors.)
Kleihues P, Cavenee WK, eds.: Pathology and Genetics of Tumours of the Nervous System. Lyon, France: International Agency for Research on Cancer, 2000.
Background Information About Childhood Craniopharyngioma
Incidence and Presentation
Craniopharyngiomas are relatively rare pediatric tumors, accounting for about 6% of all intracranial tumors in children. They are believed to be congenital in origin, and may arise from embryonic remnants. No predisposing factors have been identified.
Because craniopharyngiomas occur in the region of the pituitary gland, endocrine function and growth may be affected. Additionally, the close proximity of the tumor to the optic nerves and chiasm may result in vision problems. Some patients present with obstructive hydrocephalus due to tumor obstruction of the third ventricle.
Long-term survival for children with craniopharyngioma is generally good. Regardless of the treatment modality, long-term survival is approximately 79%.
Bunin GR, Surawicz TS, Witman PA, et al.: The descriptive epidemiology of craniopharyngioma. J Neurosurg 89 (4): 547-51, 1998.
Sanford RA, Muhlbauer MS: Craniopharyngioma in children. Neurol Clin 9 (2): 453-65, 1991.
Histopathologic Classification of Childhood Craniopharyngioma
Craniopharyngiomas are histologically benign and do not metastasize to remote brain locations or to areas outside the sellar region except by direct extension. They may be invasive, however, and may recur locally. They may be classified as adamantinomous or squamous papillary, with the former being the predominant form in children. They are typically composed of both a solid portion with an abundance of calcification, and a cystic component which is filled with a dark, oily fluid.
Miller DC: Pathology of craniopharyngiomas: clinical import of pathological findings. Pediatr Neurosurg 21 (Suppl 1): 11-7, 1994.
Diagnostic Evaluation of Childhood Craniopharyngioma
The results of imaging studies (computerized tomography scans and magnetic resonance imaging [MRI] scans) are often diagnostic for craniopharyngiomas, with most demonstrating intratumoral calcifications. Craniopharyngiomas without calcification may be confused with other tumor types, such as germinoma or hypothalamic/chiasmatic astrocytoma, and biopsy may be required. Magnetic resonance spectroscopy may be diagnostically helpful in some cases. MRI of the spinal axis is not routinely performed.
Apart from imaging, patients often undergo formal visual examination including visual field evaluation, and endocrine testing.
Harwood-Nash DC: Neuroimaging of childhood craniopharyngioma. Pediatr Neurosurg 21 (Suppl 1): 2-10, 1994.
Sutton LN, Wang ZJ, Wehrli SL, et al.: Proton spectroscopy of suprasellar tumors in pediatric patients. Neurosurgery 41 (2): 388-94; discussion 394-5, 1997.
There is no generally applied staging system for childhood craniopharyngiomas. Patients are classified as having newly diagnosed or recurrent disease.
Treatment Options for Newly Diagnosed Childhood Craniopharyngioma
Note: Some citations in the text of this section are followed by a level of evidence. The PDQ Editorial Boards use a formal ranking system to help the reader judge the strength of evidence linked to the reported results of a therapeutic strategy. (Refer to the PDQ summary on Levels of Evidence for more information.)
There is no consensus as to the optimal treatment of newly diagnosed craniopharyngioma. Little data exists to compare the different modalities in terms of recurrence rate or quality of life. For this reason, treatment is individualized.
Because these tumors are histologically benign, it may be possible to remove all the visible tumor resulting in long-term disease control. Many surgical approaches have been described, and the route should be determined by the size, location, and extension of the tumor. A transsphenoidal approach may be possible in some small tumors located entirely within the sella, but this is not usually possible in children, in which case a craniotomy is usually required.
Gross total resection is technically challenging because the tumor is surrounded by vital structures, including the optic nerves and chiasm, the carotid artery and its branches, the hypothalamus, and the third cranial nerve. The tumor may be adherent to these structures, which may cause complications, and may limit the ability to remove all the tumor. The surgeon often has limited visibility in the region of the hypothalamus and in the sella, and portions of the mass may be left in these areas, accounting for some recurrences. Almost all craniopharyngiomas have an attachment to the pituitary stalk, and of the patients who undergo radical surgery, virtually all will require life-long pituitary hormone replacement with multiple medications.
Complications of radical surgery include the need for hormone replacement, obesity, alteration in mood, blindness, seizures, spinal fluid leak, false aneurysms, and difficulty with eye movements. Rare complications include death from intraoperative hemorrhage, hypothalamic damage, or stroke.
If the surgeon feels that tumor remains, or if postoperative imaging reveals residual craniopharyngioma that is not resectable, radiation therapy is generally recommended to prevent early progression.[Level of evidence: 3iiiDiii] Periodic surveillance magnetic resonance imaging is performed for several years after radical surgery because of the possibility of tumor recurrence.
Limited Surgery and Radiation Therapy
The goal of limited surgery is to establish a diagnosis, drain any cysts, and decompress the optic nerves. No attempt is made to remove tumor from the pituitary stalk or hypothalamus. The surgical procedure is followed by radiation therapy. Conventional radiation is fractionated external-beam radiation with a recommended dose of 54 Gy to 55 Gy in 1.8 Gy fractions. Surgical complications are less likely than with radical surgery. Complications of radiation include loss of pituitary hormonal function, development of late strokes and vascular malformations, delayed blindness, and development of second tumors within the radiation field. Tumor progression remains a possibility, and it is usually not possible to repeat the radiation dose. In selected cases, stereotactic radiation therapy can be delivered as a single large dose of radiation to a very small field. Proximity of the craniopharyngioma to vital structures limits this to very small tumors that are in the sella.
Intracavitary Radiation Therapy and/or Chemotherapy
Some craniopharyngiomas with a large cystic component may be treated by stereotaxic delivery of 32P or other radioactive compounds. Nonradioactive agents such as bleomycin and interferon-alpha have also been used. This is usually considered for recurrent tumors.
Sanford RA: Craniopharyngioma: results of survey of the American Society of Pediatric Neurosurgery. Pediatr Neurosurg 21 (Suppl 1): 39-43, 1994.
Sands SA, Milner JS, Goldberg J, et al.: Quality of life and behavioral follow-up study of pediatric survivors of craniopharyngioma. J Neurosurg 103 (4 Suppl): 302-11, 2005.
Sutton LN: Vascular complications of surgery for craniopharyngioma and hypothalamic glioma. Pediatr Neurosurg 21 (Suppl 1): 124-8, 1994.
Lin LL, El Naqa I, Leonard JR, et al.: Long-term outcome in children treated for craniopharyngioma with and without radiotherapy. J Neurosurg Pediatr 1 (2): 126-30, 2008.
Wara WM, Sneed PK, Larson DA: The role of radiation therapy in the treatment of craniopharyngioma. Pediatr Neurosurg 21 (Suppl 1): 98-100, 1994.
Lunsford LD, Pollock BE, Kondziolka DS, et al.: Stereotactic options in the management of craniopharyngioma. Pediatr Neurosurg 21 (Suppl 1): 90-7, 1994.
Julow J, Backlund EO, Lányi F, et al.: Long-term results and late complications after intracavitary yttrium-90 colloid irradiation of recurrent cystic craniopharyngiomas. Neurosurgery 61 (2): 288-95; discussion 295-6, 2007.
Ierardi DF, Fernandes MJ, Silva IR, et al.: Apoptosis in alpha interferon (IFN-alpha) intratumoral chemotherapy for cystic craniopharyngiomas. Childs Nerv Syst 23 (9): 1041-6, 2007.
Treatment Options for Recurrent Childhood Craniopharyngioma
Recurrence of craniopharyngioma occurs with all modalities of primary therapy. Management is determined in large part by prior therapy. Repeat attempts at gross total resection are difficult, and complications are more frequent than with initial surgery. External-beam radiation therapy is an option if this has not been previously employed. Cystic recurrences may be treated with intracavitary instillation of radioactive 32P, or bleomycin, and a reservoir may be placed to permit intermittent outpatient aspiration. Chemotherapy is generally not utilized.
Wisoff JH: Surgical management of recurrent craniopharyngiomas. Pediatr Neurosurg 21 (Suppl 1): 108-13, 1994.
Takahashi H, Nakazawa S, Shimura T: Evaluation of postoperative intratumoral injection of bleomycin for craniopharyngioma in children. J Neurosurg 62 (1): 120-7, 1985.
Late Effects in Patients Treated for Childhood Craniopharyngioma
Quality-of-life issues are important in this group of patients, and are difficult to assess due to various treatment modalities. Whereas intelligence quotient is usually maintained, behavioral issues and memory deficits attributed to the frontal lobe and hypothalamus are common, and occur in about 13% to 55% of patients in various series. Other common problems include visual loss, obesity, and the almost universal need for life-long endocrine replacement with multiple pituitary hormones.
Refer to the PDQ summary on Late Effects of Treatment for Childhood Cancer for specific information about the incidence, type, and monitoring of late effects in childhood and adolescent cancer survivors.
Hoffman HJ, De Silva M, Humphreys RP, et al.: Aggressive surgical management of craniopharyngiomas in children. J Neurosurg 76 (1): 47-52, 1992.
Additional PDQ Summaries
This information is intended mainly for use by doctors and other health care professionals. If you have questions about this topic, you can ask your doctor, or call the Cancer Information Service at 1-800-4-CANCER (1-800-422-6237).
This information is provided by the National Cancer Institute.
This information was last updated on August 3, 2009.