Paraneoplastic neurological syndromes and the role of PET imaging.

Paraneoplastic neurological syndromes are immune-mediated effects of cancer that involve the nervous system and are associated with various anti-neuronal antibodies. They can be associated with several cancers such as lung, gynecologic, thymic, testicular and others, but the diagnosis of cancer often becomes a challenge, since paraneoplastic neurological syndromes usually precede the cancer presentation by months or even years. Furthermore, even when the cancer develops, the tumor size remains small and usually undetectable by conventional diagnostic tests and imaging. Positron emission tomography imaging may be an adjunct to timely diagnosis of the occult malignancy in order to employ the specific cancer treatment. Furthermore, positron emission tomography can assess the extent of the functional abnormality in the brain and monitor its response to treatment.