title: Paraneoplastic Choreoathetosis in a Patient with Small Cell Lung Carcinoma and Anti-CRMP5/CV2: A Case Report.
abstract: BACKGROUND
  The occurrence of more or less monosymptomatic paraneoplastic choreoathetosis associated with anti-CRMP5/CV2 antibodies is rare. Typically, such autoantibodies are associated with a more classical syndrome - paraneoplastic encephalomyelitis. Frequently, small cell lung carcinoma (SCLC) is the related neoplastic finding.
  
  
  METHODS
  We present a 71-year-old woman who developed visual symptoms with papilledema and chorea. Anti-CRMP5/CV2 antibodies were a feature of both the serum and cerebrospinal fluid. Although SCLC was suspected already at the time of the initial examinations, no signs of primary or metastatic tumors were revealed on chest X-ray, MRI or whole-body PET scan. EEG and bronchoscopy were also unremarkable. However, 6 months after the onset, a repeated PET scan and subsequent bronchoscopic biopsy revealed SCLC. In spite of chemotherapy, the SCLC progressed, and the patient died 14 months after the onset of the symptoms.
  
  
  CONCLUSIONS
  We report paraneoplastic choreoathetosis associated with anti-CRMP5/CV2 antibodies. Such published case histories are rare. Although expected, we did not find any reduced signal intensity at the basal ganglia on the T1-weighted or increased intensity on the T2-weighted MRI scans.
authors.affiliation: Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Dogu
authors.initials: D
authors.lastname: Aydin
authors.affiliation: Department of Autoimmunology and Biomarkers, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Finn
authors.initials: F
authors.lastname: Somnier
authors.affiliation: Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Lisbeth H
authors.initials: LH
authors.lastname: Lassen
keywords: Anti-CRMP5/CV2 antibodies; Cancer; Movement disorder; Nervous system; Paraneoplastic choreoathetosis; Small cell lung carcinoma