This information is produced and provided by the National Cancer Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National Cancer Institute via the Internet web site at http://cancer.gov or call 1-800-4-CANCER.
Pheochromocytomas and extra-adrenal paragangliomas are rare tumors arising from neural crest tissue that develops into sympathetic and parasympathetic paraganglia throughout the body.
The most recent World Health Organization classification utilizes the term pheochromocytoma exclusively for tumors arising from the adrenal medulla, and the term extra-adrenal paraganglioma for similar tumors that arise from other locations.[1]
Incidence and Mortality
The incidence of pheochromocytoma is 2 to 8 per million persons per year.[2,3] Pheochromocytoma is present in 0.1% to 1% of patients with hypertension,[4,5,6] and it is present in approximately 5% of patients with incidentally discovered adrenal masses.[7] The peak incidence occurs in the third to fifth decades of life; the average age at diagnosis is 24.9 years in hereditary cases and 43.9 years in sporadic cases.[8] The incidence is equal between males and females.[9]
Anatomy
Pheochromocytomas and extra-adrenal paragangliomas arise from neural crest tissue. Neural crest tissue develops into sympathetic and parasympathetic paraganglia.
Sympathetic paraganglia include the following:
Parasympathetic paraganglia include the following:
Risk Factors
No known environmental, dietary, or lifestyle risk factors have been linked to the development of pheochromocytoma.
Hereditary Predisposition Syndromes
Of all pheochromocytomas and extra-adrenal paragangliomas, 25% occur in the setting of a hereditary syndrome.[8,9,10] Major genetic syndromes that have been identified as carrying an increased risk of pheochromocytoma are included in Table 1.
| Genetic Syndrome or Condition | Affected Gene | Comment |
| Multiple endocrine neoplasia type 2A and 2B | RET | (Refer to thePheochromocytoma section in the PDQ summary on theGenetics of Medullary Thyroid Cancerfor more information.) |
| von Hippel-Lindau disease | VHL | |
| Neurofibromatosis type 1 | NF1 | |
| Hereditary Paraganglioma Syndrome | SDHD[11] | Formerly referred to as familial pheochromocytoma-paraganglioma syndrome type 1 |
| SDHAF2(SDH5)[12] | Formerly referred to as familial pheochromocytoma-paraganglioma syndrome type 2 | |
| SDHC[13] | Formerly referred to as familial pheochromocytoma-paraganglioma syndrome type 3 | |
| SDHB[14] | Formerly referred to as familial pheochromocytoma-paraganglioma syndrome type 4 | |
| SDHA[15] |
Pheochromocytomas and extra-adrenal paragangliomas can also occur in the following two other very rare syndromes:
Other genetic causes of pheochromocytoma and paraganglioma are being studied. For example, truncating germline mutations in the transmembrane-encoding gene TMEM127 on chromosome 2q11 have been shown to be present in approximately 30% of affected patients with familial disease and in about 3% of patients with apparently sporadic pheochromocytomas without a known genetic cause.[18]TMEM127 is a negative regulator of mammalian target of rapamycin (mTOR) effector proteins.
Genetic counseling and testing
It has been proposed that all patients diagnosed with a pheochromocytoma or paraganglioma should consider genetic testing because the incidence of a hereditary syndrome in apparently sporadic cases is as high as 25%.[8,9,19] Early identification of a hereditary syndrome allows for early screening for other associated tumors and identification of family members who are at risk. In addition, some patients with a hereditary syndrome are more likely to develop multifocal, malignant, or recurrent disease. Knowledge of the specific genetic mutation permits increased vigilance during preoperative localization or postoperative surveillance of such patients.
Certain subgroups of patients are at very low risk of having an inherited syndrome (e.g., <2% in patients diagnosed with apparently sporadic pheochromocytoma after age 50 years).[8] Therefore, genetic testing for all patients diagnosed with a pheochromocytoma or paraganglioma may not be practical or cost effective from a population standpoint. It is currently recommended that every patient diagnosed with a pheochromocytoma or extra-adrenal paraganglioma should first undergo risk evaluation for a hereditary syndrome by a certified genetic counselor. (Refer to the NCI Cancer Genetics Services Directory for a list of genetic healthcare professionals.)
Genetic testing is often recommended in the following situations:
In patients with a unilateral pheochromocytoma and no personal or family history suggestive of hereditary disease, genetic testing can be considered if patients are between the ages of 40 years and 50 years, but genetic testing is generally not recommended if patients are older than 50 years. If a mutation is identified, predictive genetic testing should be offered to asymptomatic at-risk family members. (Refer to the PDQ summary on the Genetics of Medullary Thyroid Cancer for more information.)
Clinical Features
Patients with pheochromocytomas and sympathetic extra-adrenal paragangliomas may present with symptoms of excess catecholamine production, including the following:
These symptoms are often paroxysmal, although sustained hypertension between paroxysmal episodes occurs in 50% to 60% of patients with pheochromocytoma.[20] Episodes of hypertension can be variable in frequency, severity, and duration and are often extremely difficult to manage medically. Hypertensive crisis can lead to cardiac arrhythmias, myocardial infarction, and even death.
Patients are often very symptomatic from excess catecholamine secretion. Symptoms of catecholamine excess can be spontaneous or induced by a variety of events, including the following:
Phenoxybenzamine (blocks alpha receptors) is an effective treatment for catecholamine excess and metyrosine (blocks catecholamine synthesis) can be added if needed.
Parasympathetic extra-adrenal paragangliomas do not secrete catecholamines and usually present as a neck mass with symptoms related to compression or are incidentally discovered on an imaging study performed for an unrelated reason. In addition, approximately half of patients with pheochromocytoma are asymptomatic because their neoplasms are discovered in the presymptomatic state by either abdominal imaging for other reasons (e.g., adrenal incidentalomas) or genetic testing in at-risk family members.[21,22,23,24]
Diagnostics
The diagnosis of pheochromocytoma is usually suspected by the presence of an adrenal mass or a workup. Biochemical testing is done to document excess catecholamine secretion. Once the biochemical diagnosis of a catecholamine-secreting tumor is confirmed, localization studies should be performed. Controversy exists as to the optimal single test to make the diagnosis.
Biochemical testing
24-hour urine collection
A 24-hour urine collection for catecholamines (e.g., epinephrine, norepinephrine, and dopamine) and fractionated metanephrines (e.g., metanephrine and normetanephrine) has a relatively low sensitivity (77%–90%) but a high specificity (98%). Pretest probability is also important. The specificity of plasma-free fractionated metanephrines is 82% in patients tested for sporadic pheochromocytoma versus 96% in patients tested for hereditary pheochromocytoma.[25,26]
Plasma-free fractionated metanephrines
Measurement of plasma-free fractionated metanephrines appears to be an ideal case-detection test for patients at higher baseline risk of pheochromocytoma. Examples of these patients might include the following:
The test is associated with a relatively high false-positive rate in patients with a lower baseline risk of pheochromocytoma. Measurement of plasma-free metanephrines (e.g., metanephrine and normetanephrine) has a high sensitivity (97%–99%) but a relatively low specificity (85%).
In general, it is reasonable to use measurement of plasma-free fractionated metanephrines for initial case detection, which is followed by 24-hour measurement of urine-fractionated metanephrines and catecholamines for confirmation. Test results can be difficult to interpret because of the possibility of false-positive results. False-positive results can be caused by any of the following:[20,25]
A mildly elevated catecholamine or metanephrine level is usually the result of assay interference caused by drugs or other factors. Patients with symptomatic pheochromocytoma almost always have increases in catecholamines or metanephrines two to three times higher than the upper limits of reference ranges.[20]
Provocative testing (e.g., using glucagon) can be dangerous, adds no value to other current testing methods, and is not recommended.[28]
Imaging studies
Computed tomography (CT) imaging or magnetic resonance imaging (MRI) of the abdomen and pelvis (at least through the level of the aortic bifurcation) are the most commonly used methods for localization.[29] Both have similar sensitivities (90%–100%) and specificities (70%–80%).[29] CT imaging provides superior anatomic detail compared with MRI.
Additional functional imaging may be necessary if CT imaging or MRI fails to localize the tumor. It might also be useful in patients who are at risk for multifocal, malignant, or recurrent disease. 123 I-metaiodobenzylguanidine (MIBG) scintigraphy coupled with CT imaging provides anatomic and functional information with good sensitivity (80%–90%) and specificity (95%–100%).[29]131 I-MIBG can be used in the same way, but the image quality is not as high as with 123 I-MIBG.[30] Other functional imaging alternatives include 111 In-octreotide scintigraphy and 18 F-fluorodeoxyglucose positron emission tomography, both of which can be coupled with CT imaging for improved anatomic detail.
It is rare for localization of a catecholamine-secreting tumor to be unsuccessful if currently available imaging methods are used.
Prognosis and Survival
There are no clear data regarding the survival of patients with localized (apparently benign) disease or regional disease. Although patients with localized (apparently benign) disease should experience an overall survival approaching that of age-matched disease-free individuals, 6.5% to 16.5% of these patients will develop a recurrence, usually 5 to 15 years after initial surgery.[31,32,33]
Approximately 50% of patients with recurrent disease experience distant metastasis.[33] The 5-year survival in the setting of metastatic disease (whether identified at the time of initial diagnosis or identified postoperatively as recurrent disease) is 40% to 45%.[34]
Follow-up Evaluation
Long-term follow-up is essential for all patients with pheochromocytoma or extra-adrenal paraganglioma, even when initial pathology demonstrates no findings that are concerning for malignancy.[6]
References:
Pathologic Classification
Pheochromocytoma and paraganglioma characteristically form small nests of uniform polygonal chromaffin cells ("zellballen"). A diagnosis of malignancy can only be made by identifying tumor deposits in tissues that do not normally contain chromaffin cells (e.g., lymph nodes, liver, bone, lung, and other distant metastatic sites).
Regional or distant metastatic disease is documented on initial pathology in only 3% to 8% of patients; thus, an attempt has been made to identify tumor characteristics associated with future malignant behavior. Pathologic features associated with malignancy include the following:
In the absence of clearly documented metastases, no combination of clinical, histopathologic, or biochemical features has been shown to reliably predict the biologic behavior of pheochromocytoma. If no definite malignancy is identified, pathology generally provides insufficient prognostic information regarding the likelihood of recurrence or metastasis. These tumors cannot be considered benign by default; patients require continued lifelong surveillance.[1,2,3,4,5,6,7]
References:
There is no standard staging system for pheochromocytoma and paraganglioma. Patients have traditionally been divided into one of three categories:
Definitive treatment for localized and regional pheochromocytoma, including localized disease recurrence, consists of alpha- and beta-adrenergic blockade followed by surgery. For patients with unresectable or metastatic disease, treatment may include a combination of the following:
Only limited data are available from phase II clinical trials to guide the management of patients diagnosed with pheochromocytoma or paraganglioma. There are no phase III trials. Everything is based on case series, and the impact of survival is not known.
Treatment for patients with localized, regional, metastatic, or recurrent pheochromocytoma is summarized in Table 2.
| Pheochromocytoma | Standard Treatment Options |
| Localized Pheochromocytoma | Surgery |
| Regional Pheochromocytoma | Surgery |
| Metastatic Pheochromocytoma | Surgery |
| Palliative therapy | |
| Recurrent Pheochromocytoma | Surgery |
| Palliative therapy |
Preoperative Medical Preparation
Surgery is the mainstay of treatment for most patients; however, preoperative medical preparation is critical. Alpha-adrenergic blockade should be initiated at the time of diagnosis and maximized preoperatively to prevent potentially life-threatening cardiovascular complications, which can occur as a result of excess catecholamine secretion during surgery. Complications may include the following:
Phenoxybenzamine (a nonselective alpha-antagonist) is the usual drug of choice; prazosin, terazosin, and doxazosin (selective alpha-1-antagonists) are alternative choices.[1,2] Prazosin, terazosin, and doxazosin are shorter acting than phenoxybenzamine, and therefore, the duration of postoperative hypotension is theoretically less than with phenoxybenzamine; however, there is less overall experience with selective alpha-1-antagonists than with phenoxybenzamine.
A preoperative treatment period of 1 to 3 weeks is usually sufficient; resolution of spells and a target low normal blood pressure for age indicate that alpha-adrenergic blockade is adequate. During alpha-adrenergic blockade, liberal salt and fluid intake should be encouraged because volume loading reduces excessive orthostatic hypotension both preoperatively and postoperatively. If tachycardia develops or if blood pressure control is not optimal with alpha-adrenergic blockade, a beta-adrenergic blocker (e.g., metoprolol or propranolol) can be added but only after alpha-blockade. Beta-adrenergic blockade must never be initiated before alpha-adrenergic blockade; doing so blocks beta-adrenergic receptor-mediated vasodilation and results in unopposed alpha-adrenergic receptor-mediated vasoconstriction, which can lead to a life-threatening crisis.
References:
The standard treatment option for patients with localized pheochromocytoma is surgery.
Surgical resection, i.e., adrenalectomy, is the definitive treatment for patients with localized pheochromocytoma. A minimally invasive adrenalectomy is the generally preferred approach if the following conditions can be met:
Both anterior transabdominal laparoscopic adrenalectomy as well as posterior retroperitoneoscopic adrenalectomy have been demonstrated to be safe for the majority of patients with a modestly sized, radiographically benign pheochromocytoma.[1,2] If preoperative imaging suggests malignancy, or if the patient has an extra-adrenal paraganglioma or multifocal disease, an open approach is generally preferred.
Intraoperative hypertension can be controlled with intravenous infusion of phentolamine, sodium nitroprusside, or a short-acting calcium-channel blocker (e.g., nicardipine). Tumor removal may be followed by a sudden drop in blood pressure that may require rapid volume replacement and intravenous vasoconstrictors (e.g., norepinephrine or phenylephrine). Postoperatively, patients should remain in a monitored environment for 24 hours. Postoperative hypotension is managed primarily by volume expansion, and postoperative hypertension usually responds to diuretics.
Inherited Pheochromocytoma
The standard treatment option for patients with inherited pheochromocytoma is surgery.
The surgical management of pheochromocytoma in patients with the hereditary syndromes multiple endocrine neoplasia type 2 (MEN2) and von Hippel-Lindau (VHL) disease has been controversial. In both of these syndromes, pheochromocytoma is bilateral in at least 50% of patients; however, malignancy is very uncommon. Bilateral total adrenalectomy commits all patients to lifelong steroid dependence, and up to 25% of patients will experience Addisonian crisis (acute adrenal insufficiency).[3,4]
Current recommendations generally favor preservation of adrenal cortical tissue in patients with MEN2 and VHL syndromes when possible. Patients who initially present with unilateral pheochromocytoma should undergo unilateral adrenalectomy, and patients who present with bilateral pheochromocytomas or who develop pheochromocytoma in their remaining adrenal gland should undergo cortical-sparing adrenalectomy, when technically feasible.[3]
Evidence
In a single-institution study involving 56 patients with pheochromocytoma, 57% of patients (i.e., 17 of 30 patients) who underwent one or more cortical-sparing adrenalectomies avoided the need for routine steroid replacement; the clinical recurrence rate was low (i.e., 3 of 30 patients) and none of the patients developed metastatic disease.[5][Level of evidence: 3iiDii]
A similar approach may be reasonable in other hereditary pheochromocytoma-paraganglioma syndromes that are characterized by benign disease, but there are currently insufficient data upon which to base unequivocal recommendations. (Refer to the PDQ summary on the Genetics of Medullary Thyroid Cancer for more information on the treatment of inherited pheochromocytoma.)
Current Clinical Trials
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with localized benign pheochromocytoma. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
References:
The standard treatment option for regional pheochromocytoma is surgery.
Surgical resection is the definitive treatment for pheochromocytoma or extra-adrenal paraganglioma that is regionally advanced (e.g., from direct tumor extension into adjacent organs or because of regional lymph node involvement). Data to guide management are limited because regional disease is diagnosed in very few patients who present with pheochromocytoma.[1] However, aggressive surgical resection to remove all existing disease can render patients symptom free.[2] Surgical management of these patients may require en bloc resection of all or part of adjacent organs (e.g., kidney, liver, inferior vena cava) along with extended lymph node dissection. Patients who have undergone complete resection of regional pheochromocytoma require lifelong monitoring for disease recurrence.
Current Clinical Trials
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with regional pheochromocytoma. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
References:
Standard treatment options for metastatic pheochromocytoma include the following:
| 1. | Surgery. |
|---|---|
| 2. | Palliative therapy. |
The most common sites of metastasis for pheochromocytoma or extra-adrenal paraganglioma are lymph nodes, bones, lungs, and liver. Patients with known or suspected malignancy should undergo staging with computed tomography or magnetic resonance imaging as well as functional imaging (e.g., with 123I-metaiodobenzylguanidine [MIBG]) to determine the extent and location of disease. Patients are often very symptomatic from excess catecholamine secretion. Phenoxybenzamine is effective, and metyrosine, which is a drug that blocks catecholamine synthesis, can be added if needed.
Surgery
If all identifiable disease is resectable, including a limited number of distant metastases, surgery can provide occasional long-term remission. If disease is unresectable, surgical debulking will not improve survival; however, it is occasionally indicated for symptom palliation.
Palliative Therapy
Chemotherapy
Chemotherapy has not been shown to improve survival in patients with metastatic pheochromocytoma; however, chemotherapy can be attempted for the palliation of symptoms.
The best-established chemotherapy regimen is a combination of cyclophosphamide, vincristine, and dacarbazine (the Averbuch protocol).[1] Results of this regimen in 18 patients after 22 years of follow-up demonstrated a complete response rate of 11%, a partial response rate of 44%, a biochemical response rate of 72%, and a median survival of 3.3 years.[2][Level of evidence: 3iiiDiv]
Several other chemotherapy regimens have been used in small numbers of patients, but the overall results were disappointing.[3,4]
Targeted therapy
Novel targeted therapies are emerging as potential treatment strategies for metastatic pheochromocytoma. Disappointing initial results were reported with the mammalian target of rapamycin (mTOR) inhibitor everolimus,[5] but results from a very small number of patients treated with the tyrosine kinase inhibitor sunitinib have been more promising.[6,7]
Radiation therapy
131 I-MIBG radiation therapy has been used for the treatment of MIBG-avid metastases.[8,9] In a phase II study of high-dose 131 I-MIBG radiation therapy involving 49 patients, 8% had a complete response, 14% had a partial response, and the estimated 5-year survival was 64%.[10][Level of evidence: 3iiiDiv] Approximately 60% of metastatic pheochromocytoma or paraganglioma sites are MIBG-avid;[10] protocol-based treatment with other experimental radiolabeled agents, such as radiolabeled somatostatin, can be considered for metastases that do not take up MIBG.
Other therapy
Other palliative treatment modalities include external-beam radiation therapy (e.g., for palliation of bone metastases) and embolization, radiofrequency ablation, or cryoablation (e.g., for palliation of bulky hepatic metastases or isolated bony metastases).
Current Clinical Trials
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with metastatic pheochromocytoma. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
References:
Standard treatment options for recurrent pheochromocytoma include the following:
| 1. | Surgery. |
|---|---|
| 2. | Palliative therapy. |
After resection of a localized pheochromocytoma presumed to represent a benign tumor and documented normal postoperative biochemical testing, disease recurrence occurs in 6.5% to 16.5% of patients, and 50% of patients with disease recurrence develop metastatic disease.[1,2,3] Insufficient data exist to determine recurrence rates after complete surgical resection of regional or metastatic disease.
Surgery
Treatment for recurrent disease involves appropriate medical management (i.e., alpha-adrenergic blockade) followed by complete surgical resection, when possible.
Palliative Therapy
Palliation of symptoms, including those related to catecholamine excess and local mass effect, is the primary focus of treatment for disease that is not resectable.
The following are options for patients with local-regional or metastatic disease who are not considered candidates for surgical resection:
(Refer to the Metastatic Pheochromocytoma Treatment section of this summary for more information.)
Inherited Pheochromocytoma or Paraganglioma
Patients with inherited pheochromocytoma or paraganglioma are at risk for the development of recurrent disease in the form of additional primary tumors. Follow-up evaluation and management of additional primary tumors in such patients is essential. (Refer to the Localized Pheochromocytoma Treatment section of this summary for more information.)
Current Clinical Trials
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with recurrent pheochromocytoma. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
References:
Pheochromocytoma diagnosed during pregnancy is extremely rare (0.007% of all pregnancies).[1,2] However, this situation deserves mention because women with hereditary conditions that increase the risk of developing pheochromocytoma are often also of child-bearing age, and the outcome of undiagnosed pheochromocytoma during pregnancy can be catastrophic.
Diagnosis
Prenatal diagnosis clearly results in decreased mortality for both mother and neonate.[3] Prior to 1970, a prenatal diagnosis of pheochromocytoma was made in only approximately 25% of cases, and the mortality rate for both mother and neonate was around 50%.[4,5] The prenatal diagnosis rate rose to greater than 80% through the 1980s and 1990s, and decreased maternal and neonatal mortality rates were 6% and 15%, respectively.[4,6]
The diagnosis of pheochromocytoma should be suspected in any pregnant woman who develops hypertension in the first trimester, paroxysmal hypertension, or hypertension that is unusually difficult to treat.[2,7] Normal pregnancy does not affect catecholamine levels.[8] Thus, the usual biochemical tests are valid. Magnetic resonance imaging is the localization method of choice because it does not expose the fetus to ionizing radiation.
Treatment
Phenoxybenzamine use is safe in pregnancy, but beta-adrenergic blockers should be initiated only if needed because their use has been associated with intrauterine growth retardation.[9,10] Resection of the tumor can often be performed safely during the second trimester, or tumor resection can be combined with cesarean section when the fetus is ready to be delivered. Case reports have documented successful outcomes in the rare circumstance when surgical resection was delayed until a short time after vaginal delivery.[11] The successful management of pheochromocytoma in pregnancy depends on careful monitoring and the availability of an experienced team of specialists.
References:
The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.
Purpose of This Summary
This PDQ cancer information summary for health professionals provides comprehensive, peer-reviewed, evidence-based information about the treatment of pheochromocytoma and paraganglioma. It is intended as a resource to inform and assist clinicians who care for cancer patients. It does not provide formal guidelines or recommendations for making health care decisions.
Reviewers and Updates
This summary is reviewed regularly and updated as necessary by the PDQ Adult Treatment Editorial Board, which is editorially independent of the National Cancer Institute (NCI). The summary reflects an independent review of the literature and does not represent a policy statement of NCI or the National Institutes of Health (NIH).
Board members review recently published articles each month to determine whether an article should:
Changes to the summaries are made through a consensus process in which Board members evaluate the strength of the evidence in the published articles and determine how the article should be included in the summary.
The lead reviewer for Pheochromocytoma and Paraganglioma Treatment is:
Any comments or questions about the summary content should be submitted to Cancer.gov through the Web site's Contact Form. Do not contact the individual Board Members with questions or comments about the summaries. Board members will not respond to individual inquiries.
Levels of Evidence
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 Adult Treatment Editorial Board uses a formal evidence ranking system in developing its level-of-evidence designations.
Permission to Use This Summary
PDQ is a registered trademark. Although the content of PDQ documents can be used freely as text, it cannot be identified as an NCI PDQ cancer information summary unless it is presented in its entirety and is regularly updated. However, an author would be permitted to write a sentence such as "NCI's PDQ cancer information summary about breast cancer prevention states the risks succinctly: [include excerpt from the summary]."
The preferred citation for this PDQ summary is:
National Cancer Institute: PDQ® Pheochromocytoma and Paraganglioma Treatment. Bethesda, MD: National Cancer Institute. Date last modified <MM/DD/YYYY>. Available at: http://www.cancer.gov/cancertopics/pdq/treatment/pheochromocytoma/HealthProfessional. Accessed <MM/DD/YYYY>.
Images in this summary are used with permission of the author(s), artist, and/or publisher for use within the PDQ summaries only. Permission to use images outside the context of PDQ information must be obtained from the owner(s) and cannot be granted by the National Cancer Institute. Information about using the illustrations in this summary, along with many other cancer-related images, is available in Visuals Online, a collection of over 2,000 scientific images.
Disclaimer
Based on the strength of the available evidence, treatment options may be described as either "standard" or "under clinical evaluation." These classifications should not be used as a basis for insurance reimbursement determinations. More information on insurance coverage is available on Cancer.gov on the Coping with Cancer: Financial, Insurance, and Legal Information page.
Contact Us
More information about contacting us or receiving help with the Cancer.gov Web site can be found on our Contact Us for Help page. Questions can also be submitted to Cancer.gov through the Web site's Contact Form.
Call 1-800-4-CANCER
For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 8:00 a.m. to 8:00 p.m., Eastern Time. A trained Cancer Information Specialist is available to answer your questions.
Chat online
The NCI's LiveHelp® online chat service provides Internet users with the ability to chat online with an Information Specialist. The service is available from 8:00 a.m. to 11:00 p.m. Eastern time, Monday through Friday. Information Specialists can help Internet users find information on NCI Web sites and answer questions about cancer.
Write to us
For more information from the NCI, please write to this address:
| NCI Public Inquiries Office |
| Suite 3036A |
| 6116 Executive Boulevard, MSC8322 |
| Bethesda, MD 20892-8322 |
Search the NCI Web site
The NCI Web site provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. For a quick search, use the search box in the upper right corner of each Web page. The results for a wide range of search terms will include a list of "Best Bets," editorially chosen Web pages that are most closely related to the search term entered.
There are also many other places to get materials and information about cancer treatment and services. Hospitals in your area may have information about local and regional agencies that have information on finances, getting to and from treatment, receiving care at home, and dealing with problems related to cancer treatment.
Find Publications
The NCI has booklets and other materials for patients, health professionals, and the public. These publications discuss types of cancer, methods of cancer treatment, coping with cancer, and clinical trials. Some publications provide information on tests for cancer, cancer causes and prevention, cancer statistics, and NCI research activities. NCI materials on these and other topics may be ordered online or printed directly from the NCI Publications Locator. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237).
Last Revised: 2012-05-11
This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.
Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.