We studied whether a difference exists in the development of symptoms of the 
Lambert-Eaton myasthenic syndrome (LEMS) between patients with or without small 
cell lung cancer (SCLC). We assessed symptoms in 38 LEMS patients, 13 with SCLC, 
by interviewing them using a structured checklist, backed up by a review of 
their clinical records, and compared the frequency and time scale of symptoms 
during the course of LEMS. Bulbar (87%) and autonomic (95%) symptoms for the 
whole group were more common than reported in the literature. Frequencies of 
symptoms did not differ significantly between patients with and without SCLC, 
but symptoms in patients with SCLC appeared within a shorter time-frame, 
indicating a more rapid clinical course. The presence of a particular symptom 
associated with LEMS did not predict the presence of SCLC, but in patients with 
rapidly progressive LEMS the possibility of underlying lung cancer should be of 
particular concern.