Brain Tumors in Cats

While brain tumors in cats remain fairly uncommon, it is an issue that occurs, and that can sometimes be treated effectively. A tumor is defined as an abnormal growth of cells, and may be classified as primary or secondary. A primary brain tumor originates from cells normally found within the brain and its membranes. A secondary brain tumor, on the other hand, is one that has metastasized to the brain from a primary tumor elsewhere in the body, or that is affecting the brain by extending into brain tissue from an adjacent non-nervous system tissue, such as bone. A tumor may be either malignant (cancerous), or benign.

No specific breed of cat seems to be particularly susceptible to brain tumors, although older male cats appear to be the most likely to develop benign tumors originating from the membranes covering the brain (meningiomas).

Symptoms and Types

The most common indication of a brain tumor in cats is seizures, especially seizures that begin to occur after the cat has reached at least five years of age. There are other signs which may suggest a brain tumor, including abnormal behavior and mental status, changes in habits or learned behaviors, head pressing, over-sensitivity to pain or to being touched in the neck area, bumping into objects and doorways, and vision problems that lead to circling motions, uncoordinated movement and ataxia (drunken gait). Cats may also vocalize, or meow, more, and may not purr as frequently.

Causes

The causes and risk factors that may cause brain tumors in cats are unknown. It is speculated that various dietary, environmental, genetic, chemical, and immune system factors may be involved, but this is uncertain.

Diagnosis

Your veterinarian will perform a thorough physical exam on your pet, taking into account the background history of symptoms and possible incidents that might have precipitated this condition. Injury or trauma to the head can cause an accumulation of fluid in the skull, mimicking a tumor in outward appearance and effect. You will need to provide a thorough history of your pet's health leading up to the onset of symptoms. A tissue biopsy is the only definitive method for diagnosing brain tumors in cats. In addition, magnetic resonance imaging (MRI) scans can reveal tissue irregularities in the brain, while X-Ray and ultrasound imaging can be used to locate or rule out primary tumors in other areas of the body.

Treatment

There are three primary care methods for cats that have been diagnosed with brain tumors: surgery, radiation therapy, and chemotherapy. The major objective with these therapies is to eradicate the tumor or reduce its size, and to control secondary effects, such as fluid build-up in the brain (known as cerebral edema) that may result from a brain tumor. Surgery may be used to completely or partially remove tumors, while radiation therapy and chemotherapy may help shrink tumors. Various medications can be prescribed to slow tumor growth and to cope with side-effects, such as seizures.

Living and Management

Throughout and after treatment, examinations of the nervous system should be performed regularly. Imaging with computed tomography (CT), computerized axial tomography (CAT), or a magnetic resonance imaging (MRI) scan may be necessary. It is important to watch for complications and indications that your cat may still be a danger. Seizure, or aspiration pneumonia due to weakened swallowing reflexes are associated with increased pressure of cerebrospinal fluid within the skull cavity. The prognosis for animals with brain tumors is not very good, and is short term at best.

Prevention

Due to the fact that the causes of brain tumors are unknown, it is difficult to establish specific prevention methods.