Paraneoplastic Syndrome

Paraneoplastic syndrome is usually associated with neurological dysfunctioning, endocrine and cutaneous disorders.

The following are the signs and symptoms of the syndrome:

• Walking difficulty
• Difficulty in maintaining balance
• Seizures
• Vision disturbances
• Muscle coordination loss
• Fever [6]
• Vertigo
• Dizziness
• Sleep disturbances
• Loss of fine motor skills
• Loss of memory
• Trouble in eating and swallowing food
• Cognitive impairment 
• Weakness
• Cutaneous itching [7]

Diagnosis of paraneoplastic syndrome is a difficult affair and is often misdiagnosed. The diagnosis begins with preliminary clinical examination to study the reflexes, mental functioning, muscle tone and its strength, balance, coordination and sensory functioning.

Blood work would be done to analyze the antibodies associated with paraneoplastic syndrome [8]. A lumbar puncture examination to test the cerebrospinal fluid (CSF) for antibodies is carried out.

Several imaging tests such as CT scan, MRI, PET and PET-CT are employed for further diagnosis of the syndrome. Positron emission tomography (PET) scan is a method wherein radioactive elements are injected into the body to generate 3D images. This helps in studying the degree of metabolism of tumor cells and also provides information related to brain abnormalities.

The primary goal of treatment consists of managing the tumor cells and suppressing the immune system to stop the abnormal behavior. These objectives are carried out through various methods such as:

• Surgical procedures along with chemotherapy and radiation therapy to remove the tumor cells and suppress its growth. Surgery is largely dependent on the nature and the location of the malignant cells.
• Medications like corticosteroids and immunosupressants are employed for treating the condition. Corticosteroids work by reducing the inflammation and immunosupressants suppress the action of the immune system. Based on the type of paraneoplastic syndrome present, other medications are also given to decrease the seizures and enhance the nerve to muscle transmission.
• Plasmaphersis is conducted to rid the body of the antibodies by replacing the blood plasma.
• Individuals are also given intravenous immunoglobulin in which healthy antibodies from donors are transferred to the body [9].

In addition to the above mentioned treatment methods, individuals are also subjected to physical and speech therapies to improvise the walking ability and restore muscle control.

Prognosis of paraneoplastic syndrome is usually poor. There are no available treatments and this syndrome has no known cure. The stage at which the condition is diagnosed generally decides the outcome of the disease. Treatment methods employed to treat the cancer can have some positive effect on the condition. The majority of patients suffering from paraneoplastic syndrome succumbs to secondary infections which is the common cause of mortality [5].

Complications

Complications of paraneoplastic syndrome include the following:

• Permanent neurological damage
• Cerebellar degeneration
• Confusion
• Delirium
• Seizures
• Coma 
• Death

Paraneoplastic syndrome does not occur as a direct effect of the cancer cells [3]. It occurs due to activation of the immune system that behaves in an abnormal fashion in response to cancer cells and in turn attacks the body’s healthy cells giving rise to associated disease conditions.

A secondary phenomenon that explains the development of paraneoplastic syndrome is that the cancer cells releases cellular components which are physiologically active in nature. These components serve as tumor markers paving way for development of paraneoplastic syndrome.

Paraneoplastic syndrome is a rare occurrence that commonly affects the adult and the elderly population. Children seldom fall prey to such syndromes. It has been estimated that about 20% of the population with cancer develop paraneoplastic syndrome. However, the exact incidence of this syndrome is not known.

The pathophysiology of paraneoplastic syndrome is a complex one. There are basically two theories defining the onset of such a kind of syndrome. The preliminary one states that the immune system of individuals with cancer behaves in an abnormal fashion and begins attacking the normal cells along with the tumor cells [4]. Such an activity deteriorates the neurological functioning of the brain giving rise to paraneoplastic syndrome.

In yet another theory, researchers explain that the physiologically active components released by the tumor cells can attack the other body organs giving rise to several associated secondary conditions such as sensory neuropathy, neuromyotonia, myasthenia gravis, cerebellar degeneration, stiff–person syndrome and encephalomyelitis to name a few. These syndromes are collectively referred to as paraneoplastic syndrome.

So far there are no approaches designed to prevent the development of paraneoplastic syndrome. However, if the condition is diagnosed on time then the onset of complications can be prevented to certain extent. Primary screening tests may be used among patients with strong familial history of breast and colon cancer [10].

Paraneoplastic syndrome is characterized by abnormal response of the immune system to the presence of malignant tumors. Patients suffering from cancer of the lungs, breast, lymphatic system or the ovaries are known to contract paraneoplastic syndrome.

Such a kind of a syndrome is also termed as paraneoplastic syndrome of the central nervous system because many affected individuals suffer from neurologic disorders [1]. In some instances, paraneoplastic symdrome involves the peripheral nervous system [2].

The signs and symptoms of the syndrome begin to show effect within days or weeks much before the tumor is diagnosed. Middle aged and the geriatric population fall easy prey to paraneoplastic syndrome.

Definition

Paraneoplastic syndrome is a rare group of disorders that develop in patients suffering from cancer. It however does not occur due to the direct effect of cancer but occurs as a result of abnormal behavior of immune system that attacks the body’s healthy cells. It can also occur due to the release of cellular components of the tumor cells that have an adverse effect on other organs of the body.

Cause

Paraneoplastic syndrome occurs in patients suffering from lung, stomach or breast cancer. The exact cause that triggers the development of such a syndrome is not known. However, researchers believe that the faulty behavior of the immune system can cause paraneoplastic syndrome.

Symptoms

Common symptoms of paraneoplastic syndrome include loss of muscle tone, difficulty in walking, speaking and swallowing, loss of fine motor skills, dementia, seizures, sleep problems, vertigo and dizziness. Individuals also suffer from memory loss, vision problems and loss of sensation in the limbs.

Diagnosis

Diagnosis of the syndrome is done by analyzing the clinical signs and symptoms. In addition, blood test and lumbar puncture test is done for detecting the presence of antibodies. Various imaging tests are carried out for detecting the tumor locations and determining the extent of spread of cancer.

Treatment

Primary mode of treatment consists of removal of the tumors from the body. This is followed by medications to suppress the immune response and also to improve the symptoms. Plasma transfer may also be required in some patients. 

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5. Leger S, Picard D, Ingen-Housz-Oro S, Arnault JP, Aubin F, et al. Prognostic factors of paraneoplastic pemphigus. Arch Dermatol. Oct 2012; 148(10):1165-72.
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10. Kawasoe T, Yamamoto Y, Okumura Y, et al. A case report of paraneoplastic neurological syndrome associated with occult breast cancer. Breast Cancer.