Paraneoplastic syndromes are not caused by cancer cells directly disrupting nerve function, by the cancer spreading (metastasis), or by other complications such as infections or treatment side effects. Instead, they occur alongside the cancer as a result of the activation of your immune system.

Researchers believe paraneoplastic syndromes are caused by cancer-fighting abilities of the immune system, particularly antibodies and certain white blood cells, known as T cells. Instead of attacking only the cancer cells, these immune system agents also attack the normal cells of the nervous system and cause neurological disorders.

Other cancer-related neurological problems

Other neurological problems may be related to cancers. For example, tumors may develop in your brain or spinal cord. Non-nervous system tumors can cause tissue injury that results in injury to the nervous system. For example, a tumor may compress a nerve or the spinal cord.

Cancers cells may migrate away from the main area of growth (metastasize) to other areas of the body. Malignant cells from your lungs, for example, may metastasize to your brain.

Also, cancer treatments such as radiation therapy and chemotherapy can affect neurological function. However, these complications of cancer aren't considered paraneoplastic syndromes, even though they may produce similar signs and symptoms.

Apr. 30, 2014

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