Background: Paraneoplastic neurologic syndromes, although rare, cause significant morbidity and mortality. They are thought to be immunologically mediated, but to date those involving the central nervous system (CNS) have not been particularly responsive to immunologic therapy. The use of the novel immunomodulator, protein A immunoadsorption, was explored to address this question.
Methods: Six patients with neurologic paraneoplastic syndromes were treated with this technique, using the "off line" method. Two hundred fifty ml of plasma was perfused through a column containing protein A covalently attached to a silica matrix. The plasma was then returned to the patient.
Results: Five of the patients responded to the therapy, with complete and durable responses in three patients with opsoclonus-myoclonus, objective, though transient, improvement in one patient with paraneoplastic brainstem encephalitis associated with a Merkel cell tumor, and stabilization and partial improvement in one patient with paraneoplastic limbic encephalitis. The patient without response developed a cutaneous vasculitis after the second treatment, and therapy was discontinued.
Conclusions: This therapy appears beneficial for a number of paraneoplastic syndromes, most dramatically in the opsoclonus/myoclonus syndrome.