Anti-Ma2 Antibody-Mediated Paraneoplastic Cerebellar Degeneration and Myeloneuropathy Secondary to Lymphoma

A 61-year-old woman with a history of untreated low-grade B-cell lymphoma presented with blurry vision, unsteadiness, and worsening pain on touching skin of the upper trunk was enrolled. Blurry vision was attributed to oscillopsia from downbeat nystagmus, which later evolved into macrosaccadic oscillations. MRI brain and spine showed mild, longitudinally extensive T2 hyperintensity in the central gray matter of the spinal cord extending from the medulla to T11 level. Serum paraneoplastic panel was negative; however, she had very high titers of anti-Ma2 antibodies in cerebrospinal fluid. The diagnosis of paraneoplastic neurological syndrome was made. Empiric treatment with high dose of intravenous steroids followed by intravenous immunoglobulin infusions did not improve her symptoms. An extensive search for an underlying tumor commenced and was initially unrevealing. However, two-month follow-up positron emission tomography scan showed increased uptake in a right pulmonary nodule, which when biopsied confirmed diagnosis of extranodal marginal zone lymphoma. The final diagnosis was anti-Ma2 antibody-mediated paraneoplastic cerebellar degeneration and myeloneuropathy secondary to lymphoma.