The Utility of Paraneoplastic Antibody Testing in the Diagnosis of Motor Neuron Disease (P7.076)

OBJECTIVE: Evaluate the role of paraneoplastic autoantibody testing in the diagnosis of motor neuron disease. BACKGROUND: Motor neuron disease (MND) is a group of progressive neurodegenerative disorders. There have been rare case reports of patients presenting as a paraneoplastic phenomenon, though the possibility that the MND and neoplasm are chance associations remains for these isolated reports. To our knowledge, there has not been a previous study to determine the usefulness of paraneoplastic antibody testing in the setting of DESIGN/METHODS: Retrospective chart review study of patients with MNDs seen at the University of Washington Medical Center over the period from 2007 to 2014. RESULTS: Of 316 patients reviewed, 44[percnt] (n = 138) were evaluated by a paraneoplastic autoantibody panel sent to the Mayo Clinic. 73[percnt] (n = 101) were diagnosed with amyotrophic lateral sclerosis (ALS), fulfilling possible, probable or definite revised El Escorial criteria, and 27[percnt] (n = 37) were diagnosed as having suspected ALS or another MND. Thirteen patients (9[percnt]) tested positive for at least one paraneoplastic antibody. Three of these patients had negative diagnostic testing for malignancy. The first patient had antibodies to both voltage gated calcium channel and ganglionic acetylcholine receptor and mediastinal lymphadenopathy that was shown by lymph node biopsy to be a reactive process rather than malignancy. The second patient had antibodies to GAD-65 and received a short course of corticosteroids and intravenous gammaglobulin with no improvement, subsequently dying. The third patient had antibodies to voltage-gated potassium channel and negative CT scans of the chest, abdomen and pelvis. CONCLUSIONS: The presence of paraneoplastic autoantibodies in patients with MND is rare and not typically associated with malignancy. Testing for paraneoplastic antibodies does not appear to change the diagnosis, management, or outcome in the setting of MND and is therefore of limited value. Study Supported by: Disclosure: Dr. Al-Bustani has nothing to disclose. Dr. Simonson has nothing to disclose. Dr. Marshall has nothing to disclose. Dr. Vetrovs has nothing to disclose. Dr. Wener has received royalty payments from Up To Date and MTS. Dr. Wener9s employer has received research support from BioRad Laboratories. Dr. Weiss has received personal compensation for activities with Walgreens, Grifols, and Nufactor. Dr. Weiss has received research support from Clinical Trials Research Unit/Northeast ALS Consortium and the ALS Therapy Alliance. Dr. Wang has nothing to disclose.