What causes Lambert-Eaton Myasthenic syndrome?
Lambert-Eaton myasthenic syndrome (LEMS) is an uncommon neuromuscular disorder characterized by weakness in muscles of the upper arms and upper legs, and less commonly, muscles of the neck, speech, swallowing, breathing and eye movement. LEMS is an autoimmune disease, referring to the fact that antibodies are produced by the body against its own tissues. The frequency of LEMS is less than one in every 1,000,000 people. The disorder is not hereditary. Lambert-Eaton myasthenic syndrome (LEMS) is associated in 40% of cases with cancer, most often with small cell cancer of the lung and less often with other tumors. The neuromuscular defect in LEMS is due to insufficient release of the neurotransmitter acetylcholine by nerve cells.