A paraneoplastic syndrome is a disease or symptom that is the consequence of the presence of cancer in the body, but is not due to the local presence of cancer cells. These phenomena are mediated by humoral factors (by hormones or cytokines) excreted by tumor cells or by an immune response against the tumor.
Sometimes the symptoms of paraneoplastic syndromes show even before the diagnosis of a malignancy.
A particularly devastating form of paraneoplastic syndromes is a group of disorders classified as paraneoplastic neurological disorders (PNDs). These paraneoplastic disorders affect the brain and central nervous system and they are degenerative. Symptoms of paraneoplastic neurological disorders include ataxia (difficulty with walking and balance), dizziness, nystagmus (rapid uncontrolled eye movements), difficulty swallowing, loss of muscle tone, loss of fine motor coordination, slurred speech, memory loss, vision problems, sleep disturbances, dementia, seizures, sensory loss in the limbs.
The most common cancers associated with paraneoplastic neurological disorders are breast, ovarian and lung cancer, but many other cancers have been linked to PNDs as well.
Treatment options include:
Therapies to eliminate the underlying cancer such as chemotherapy, radiation and surgery, and
Therapies to reduce or slow neurological degeneration. Rapid diagnosis and treatment is critical for the patient to have the best chance of recovery. Since these disorders are relatively rare, few doctors have seen or treated PNDs. Therefore, it is important that PND patients consult with a specialist with experience in diagnosing and treating paraneoplastic neurological disorders.
The International Paraneoplastic Association (IPA) is an organization dedicated to providing support and information to those affected by paraneoplastic neurological disorders.