A brainstem paraneoplastic syndrome associated with prostate cancer

Background:Paraneoplastic syndromes are seldom observed with prostate cancer. A rare paraneoplastic brainstem syndrome associated with prostate cancer is described, and the presence of antineuronal antibodies with this syndrome is demonstrated for the first time.Setting:Tertiary referral centre for neurological disorders.Patient:This 59-year-old man developed ophthalmoplegia, dysarthria, dysphagia, pruritus, ataxia, corticobulbar and corticospinal signs in association with prostate cancer. The disorder was unaffected by treatment of the underlying malignancy, but responded initially to high-dose corticosteroid administration and intravenous immunoglobulins.Results:Antibody to intracellular neuronal antigens was demonstrated in both the serum and the cerebrospinal fluid.Conclusions:This unique paraneoplastic syndrome chiefly affecting the brainstem may be a diagnostic clue to the presence of unsuspected prostate adenocarcinoma. Further studies will be required to determine the precise antigenic target.