BBB Seminar: Christian A. Vedeler
Paraneoplastic neurological syndromes
Christian A. Vedeler, Department of Neurology, Haukeland University Hospital, Bergen
Paraneoplastic neurological syndromes (PNS) are rare, but very disabling disorders. The most common PNS include paraneoplastic encephalomyelitis (often in combination with neuropathy), paraneoplastic cerebellar degeneration, opsoclonus-myoclonus, stiff-person syndrome, visual paraneoplastic syndromes, peripheral neuropathy and disorders of the neuromuscular junction. They arise as remote effects of several different types of tumours, most frequently small cell lung cancer, breast cancer, gynaecological tumours, and lymphoma. PNS occur in approximately 1% of cases with such tumours. Onconeural antibodies represent an important shortcut to the diagnosis of PNS and the detection of such antibodies often directs the search of the underlying tumour. These antibodies may also be of pathogenic importance as they target critical functional epitopes that are probably linked to neuronal death. However, cytotoxic T lymphocytes may also play a major or complementary pathogenic role. It is important to identify PNS for the following reasons: 1) PNS may involve any part of central and/or peripheral nervous systems and may mimic other neurological complications of cancer such as metabolic deficits, coagulopathy, infection and side effects of therapy; 2) In 60%-70% of patients, the PNS develops before the tumour is manifest. Recognition of the paraneoplastic disorder may, therefore, lead to early diagnosis of the tumour with potential for better treatment response of both the underlying tumour and the paraneoplastic syndrome.
Host: Clive R. Bramham, Department of Biomedicine