Paraneoplastic cerebellar degeneration in a patient with anti-Yo antibodies and prostate adenocarcinoma

Abstract

Paraneoplastic cerebellar degeneration is the damage to cerebellar Purkinje cells by anti-Yo antibodies synthesized by the immune system in response to the generation of neuronal proteins by malignant prostate adenocarcinoma cells in 25% of cases. Neurological symptoms of cerebellar lesions appear on average 2 years before cancer manifestation in 70% of patients. During the early stages of the disease, when the tumor cannot be visualized nor clinically manifested, a high titer of anti-Yo antibodies in the cerebrospinal fluid of patients. The presence of anti-Yo antibodies prostate cancer with a clinically latent course was present in 90–98% of patients with cerebellar ataxia. Onconeural autoantibodies (IgG) are well detected in serum by immunoblotting and indirect immunofluorescence. The death of Purkinje cells of the granular and molecular layers of the cerebellar cortex, moderate perivascular lymphocytic infiltration, and further proliferation of microglia lead to atrophy. Inflammatory infiltrates may also be present in the brainstem and cortex, although in significantly less number in compar the cerebellum. This difference accounts for the presence of additional neurological symptoms. The results of the brain MR imaging at the initial stages of paraneoplastic cerebellar degeneration are of little informative value, and degenerative changes in the cerebellum are revealed only a few months later with a subsequent increase in neurological deficit. Removal of malignant tumors leads to the regression of neurological symptoms in 80% of cases. This finding confirms the advisability of a targeted oncological search in patients with symptoms of paraneoplastic cerebellar degeneration and positive onconeural antibodies in the serum. Immunomodulatory therapy, including the use of intravenous immunoglobulin, plasmapheresis, and hormone therapy, is also effective in the treatment of neurological disorders. This paper describes a clinical case of paraneoplastic cerebellar degeneration in a 65-year-old male, with the appearance of neurological symptoms 5 months before the diagnosis of prostate adenocarcinoma. The difficulties of differential diagnosis of this neurological disorder and the course of neurological diseases in the background of tumor removal and conducted immunotherapy are discussed.