title: Anti-Ri-associated paraneoplastic brainstem cerebellar syndrome with coexisting limbic encephalitis in a patient with mixed large cell neuroendocrine lung carcinoma.
abstract: Paraneoplastic neurologic syndromes (PNS) can be the first manifestations of occult malignancies. If left untreated, PNS often lead to significant morbidity and mortality. Anti-Ri (anti-neuronal nuclear antibody type 2 [ANNA-2]) autoantibodies are commonly associated with breast and small cell lung cancers. Cases of anti-Ri paraneoplastic cerebellar degeneration are reported, but few describe severe nausea and coexisting limbic encephalitis as the major presenting features. We report a 75-year-old woman with medically-intractable emesis, encephalopathy, diplopia, vertigo, and gait ataxia for 3 months. Examination revealed rotary nystagmus, ocular skew deviation, limb dysmetria, and gait ataxia. After two courses of intravenous immunoglobulin, there was minimal improvement. Anti-Ri antibodies were positive in serum only. CT scan identified a 2.0 cm left lung mass, and histopathology revealed large cell neuroendocrine carcinoma with admixed adenocarcinoma non-small cell lung carcinoma (NCSLC). Though the patient achieved nearly complete clinical recovery after tumor resection, anti-Ri levels remained high at 20 months post-resection. To our knowledge this is the first report of a paraneoplastic brainstem cerebellar syndrome with coexisting limbic encephalitis involving anti-Ri positivity and associated mixed neuroendocrine/NSCLC of the lung with marked improvement after tumor resection.
authors.affiliation: Department of Neurology, Albany Medical Center, 47 New Scotland Avenue, Albany, NY 12208, USA. Electronic address: mitcheam@mail.amc.edu.
authors.forename: Amber N
authors.initials: AN
authors.lastname: Mitchell
authors.affiliation: Department of Surgery, Section of Thoracic Surgery, Albany Medical Center, Albany, NY, USA.
authors.forename: Charles T
authors.initials: CT
authors.lastname: Bakhos
authors.affiliation: Department of Neurology, Albany Medical Center, 47 New Scotland Avenue, Albany, NY 12208, USA.
authors.forename: Earl A
authors.initials: EA
authors.lastname: Zimmerman
mesh_terms: D000230:Adenocarcinoma / Q000150:complications* / Q000473:pathology; D000368:Aged; D000974:Antibodies, Antinuclear; D000912:Antibodies, Neoplasm / Q000276:immunology*; D002289:Carcinoma, Non-Small-Cell Lung / Q000150:complications* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D020363:Limbic Encephalitis / Q000150:complications* / Q000473:pathology / Q000601:surgery; D008168:Lung / Q000473:pathology; D008175:Lung Neoplasms / Q000150:complications* / Q000473:pathology; D009325:Nausea / Q000209:etiology; D018358:Neuroendocrine Tumors / Q000150:complications* / Q000473:pathology / Q000601:surgery; D019635:Neurosurgical Procedures; D020362:Paraneoplastic Cerebellar Degeneration / Q000150:complications* / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014839:Vomiting / Q000209:etiology
chemical_list: D000974:Antibodies, Antinuclear; D000912:Antibodies, Neoplasm; C487483:ANNA-2 antibody
keywords: Cerebellum; Paraneoplastic syndrome; Vertigo