Posterior fossa tumor
Infratentorial brain tumors; Brainstem glioma
Posterior fossa tumor is a type of brain tumor located in or near the bottom of the skull.
Causes
The posterior fossa is a small space in the skull, found near the brainstem and cerebellum. The cerebellum is the part of the brain responsible for movement, balance, and coordination. The brainstem is responsible for controlling vital body functions, such as breathing.
If a tumor grows in the area of the posterior fossa, it can block the flow of spinal fluid and cause increased pressure on the brain and spinal cord.
Most tumors of the posterior fossa are primary brain cancers. They start in the brain, rather than spreading from somewhere else in the body.
Posterior fossa tumors have no known causes or risk factors.
Symptoms
Symptoms occur very early with posterior fossa tumors and may include:
-
Drowsiness
Drowsiness
Drowsiness refers to feeling abnormally sleepy during the day. People who are drowsy may fall asleep in inappropriate situations or at inappropriate...
-
Headache
Headache
A headache is pain or discomfort in the head, scalp, or neck. Serious causes of headaches are rare. Most people with headaches can feel much better...
- Imbalance
- Nausea
-
Uncoordinated walk (
ataxia
)
Ataxia
Uncoordinated movement is due to a muscle control problem that causes an inability to coordinate movements. It leads to a jerky, unsteady, to-and-fr...
-
Vomiting
Vomiting
Nausea is feeling an urge to vomit. It is often called "being sick to your stomach. "Vomiting or throwing-up is forcing the contents of the stomach ...
Symptoms from posterior fossa tumors also occur when the tumor damages local structures, such as cranial nerves. Symptoms of cranial nerve damage include:
- Dilated pupils
- Eye problems
- Face muscle weakness
- Hearing loss
- Loss of feeling in part of the face
- Taste problems
- Unsteadiness when walking
- Vision problems
Exams and Tests
Diagnosis is based on a thorough medical history and physical exam, followed by imaging tests. The best way to look at the posterior fossa is with an MRI scan. CT scans are not helpful to see that area of the brain in most cases.
MRI
A magnetic resonance imaging (MRI) scan is an imaging test that uses powerful magnets and radio waves to create pictures of the body. It does not us...
The following procedures may be used to remove a piece of tissue from the tumor to help with diagnosis:
-
Open brain surgery, called a posterior
craniotomy
Craniotomy
Brain surgery is an operation to treat problems in the brain and surrounding structures.
- Stereotactic biopsy
Treatment
Most tumors of the posterior fossa are removed with surgery, even if they are not cancerous. There is limited space in the posterior fossa, and the tumor can easily press on delicate structures if it grows.
Depending on the type and size of the tumor, radiation treatment may also be used after surgery.
Support Groups
You can ease the stress of illness by joining a support group whose members share common experiences and problems.
Support group
The following organizations are good resources for information on cancer:American Cancer Society -- www. cancer. orgCancerCare -- www. cancercare. or...
Outlook (Prognosis)
A good outlook depends on finding the cancer early. A total blockage in the flow of spinal fluid can be life threatening. If tumors are found early, surgery can lead to long-term survival.
Possible Complications
Complications may include:
- Cranial nerve palsies
- Herniation
-
Hydrocephalus
Hydrocephalus
Hydrocephalus is a buildup of fluid inside the skull that leads to brain swelling. Hydrocephalus means "water on the brain. "
-
Increased intracranial pressure
Increased intracranial pressure
Increased intracranial pressure is a rise in the pressure inside the skull that can result from or cause brain injury.
When to Contact a Medical Professional
Call your health care provider if you have regular headaches that occur with nausea, vomiting, or vision changes.
References
Arriaga MA, Brackmann DE. Neoplasms of the posterior fossa. In: Flint PW, Haughey BH, Lund V, et al, eds. Cummings Otolaryngology: Head & Neck Surgery. 6th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 177.
Dorsey JF, Hollander AB, Alonso-Basanta M, et al. Cancer of the central nervous system. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE, eds. Abeloff's Clinical Oncology . 5th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2014:chap 66.
Review Date: 2/12/2016
Reviewed By: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.