Paraneoplastic Syndromes of the Nervous System

Symptoms:

Some of the neurological paraneoplastic syndromes' common features are:

• Dizziness
• Difficulty maintaining balance
• Numbness and tingling in the arms and legs
• Difficulty swallowing
• Difficulty walking
• Loss of muscle tone
• Loss of fine motor coordination
• Seizures
• Slurred speech
• Dementia
• Memory loss
• Sleep disturbances
• Vision problems

Paraneoplastic syndromes of the nervous system may cause some of the following disorders:

Cerebellar degeneration:

In this disorder, nerve cells are killed in the brain area that is in charge of motor functions and balance (cerebellum). Wide-legged, unsteady walk is one of the common signs, and is often accompanied by tremor in the trunk of the body.

Encephalomyelitis:

The brain and the spinal cord become inflamed in this condition, causing a range of symptoms from numbness to respiratory failure.

Lambert-Eaton myasthenic syndrome:

The most frequent signs and symptoms of this disorder are muscle weakness, fatigue, difficulty swallowing and vision changes. These symptoms are mainly caused by the disrupted communication between the nerves and muscles.

Limbic encephalitis:

In this disorder, memory loss, drowsiness, confusion, disorientation and seizures, among other signs and symptoms are caused by the swelling of some portions of the brain.

Myasthenia gravis:

In this disorder, any of the muscles under voluntary control, including those in the face, eyes, arms and legs are fatigued rapidly, which is a characteristic feature of this disorder. Its effects may reach as far as the muscles involved in chewing, swallowing, talking and breathing. Tumor of the thymus gland (thymoma) is often associated with this disorder.

Neuromyotonia:

This condition is characterized by abnormal nerve impulses from the motor neurons of the peripheral nerves, and it is also called Isaacs syndrome. Twitching, progressive stiffness, muscle cramps and slowed movement, among other signs and symptoms are caused by these impulses.

Neuropathies:

This condition is the damage of the nerves. Paraneoplastic syndromes may include autonomic neuropathy and sensory neuropathy. The former is damage to the nerves that regulate the body functions that are involuntary such as heart rate, blood pressure, perspiration and digestion. The latter is the damage to sensory nerves in the peripheral nervous system, which include nerves in the face, arms, legs, torso and some nerves in the skull.

Opsoclonus-myoclonus:

Damage to the nervous system may result in rapid, irregular eye movements (opsoclonus) coupled with quick involuntary muscle jerks (myoclonus).

Stiff person syndrome:

Progressive, severe muscle stiffness or rigidity, mainly in the spine and legs, along with the possibility of painful muscle spasms, are caused by this disabling neurological disorder.
 

Causes:

Paraneoplastic syndromes are a case associated with patients of cancer. In the particular case of the nervous system, it is thought that these syndromes develop because of cancer-fighting antibodies or some white blood cells, known as T cells, which are activated to resist cancer. These syndromes develop when these antibodies start attacking the cells of the nervous system among other normal cells, instead of attacking the cancer cells.

Statistically, people who have lung, breast or ovarian cancer, are more likely to develop neurological paraneoplastic syndromes. Usually, this is an autoimmune condition in response to the presence of cancer. Why some patients with cancer develop this response, and others do not is yet unknown. no risk factors have been revealed yet that connect cancer to neurological paraneoplastic syndromes.
 

Complications:

When a patient starts receiving cancer treatment, signs and symptoms of neurological paraneoplastic syndromes are decreased or stopped altogether. However, there is nothing to be done if a paraneoplastic syndrome has already caused irreversible neuron damage, which might result in permanent disability in some cases.
 

Treatments:

Treatment of neurological paraneoplastic syndromes basically starts with the treatment of the cancer itself, and in some cases it is meant to stop the response of the immune system from causing the neurological signs and symptoms. Depending on the type of paraneoplastic syndrome, the treatment course is decided. Treatment methods include:

MEDICATIONS:

Two types of medications are prescribed, the first is to fight the cancer itself and the second is to prevent the immune system from causing damage to the nervous system, that might include the followings:

• Cyclosporine
• Tacrolimus
• Corticosteroids, such as prednisone
• Cyclophosphamide

THERAPIES:

Physical therapy:

This is meant to make the patient able to recover some of the nerve and muscle function that have been damaged by the means of specific exercises.

Speech therapy:

A speech therapist aid the patient in the recovering of communication skills in case a paraneoplastic syndrome has affected the ability of the patient to speak.

OTHER PROCEDURES:

Plasmapheresis:

This procedure calls for removal of the plasma from the blood, and it is also called plasma exchange. After extracting the plasma from the blood which contains the unwanted paraneoplastic antibodies, red and white blood cells along with the platelets are returned to the bloodstream. During this process, the extracted plasma is replaced with other fluids.

Intravenous immunoglobulin (IVIg):

In this process, a patient is given high doses of immunoglobulin, for this has the ability to block the action of the damaging antibodies. This immunoglobulin contains healthy antibodies from blood donors.
 

Prognosis:

Not available

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