Lambert-Eaton myasthenic syndrome and polyneuropathy in a patient with epidermoid carcinoma of the lung

We describe a patient affected by the Lambert-Eaton myasthenic syndrome, sensory motor axonal neuropathy and epidermoid carcinoma of the lung. Serum autoantibodies to voltage-operated calcium channels were detected. After lobectomy, voltage-operated calcium channel-related structures were demonstrated in the patient's tumor. By immunocytochemistry, the patient's IgG reacted with neural structures and particularly with intermediate filaments. We think that these autoantibodies may be implicated in the pathogenesis of the neurological symptomatology.