Eaton-Lambert syndrome in a patient with acute T cell lymphocytic leukemia.

We have reported the first case of the Eaton-Lambert syndrome associated with leukemia in an adult, a 74-year-old woman with acute T cell lymphocytic leukemia and a mediastinal mass accompanied by weakness of the upper and lower extremities and pain in the lower extremities. Electromyographic studies were diagnostic of the syndrome. Treatment with guanidine hydrochloride resulted in clinical improvement of the neuromuscular disease, but the patient died of refractory leukemia.