LAMBERT-EATON MYASTHENIC SYNDROME (LEMS) IN ASSOCIATION WITH LYMPHOPROLIFERATIVE DISORDERS

LEMS is a presynaptic neuromuscular junction disorder typically associ ated with small cell lung carcinoma, The characteristic electrophysiol ogical abnormality is a low amplitude compound muscle action potential that shows a marked increment after short maximal contraction or brie f tetanic nerve stimulation, Here we describe 3 patients who had LEMS in association with lymphoproliferative disorder, The first patient ha d Castleman's syndrome with typical clinical and electrophysiological features of LEMS, which responded partially to treatment with 3-4-diam inopyridine. The second patient was a 7-year-old boy who had an unusua l acute onset of LEMS associated with relapse of his Burkitt's leukemi a, The third patient was a 60-year-old woman with non-Hodgkin's lympho ma, These 3 patients (together with 6 additional patients identified i n the literature) lead us to suggest that lymphoproliferative diseases are another, hitherto unrecognized, type of malignancy associated wit h LEMS, Thus, any patient with these malignancies and unexplained musc le weakness should have electrophysiological evaluation for LEMS. (C) 1995 John Wiley and Sons, Inc.