We welcome patients to visit the Cardiothoracic Surgery Department of Tianjin Medical University General Hospital or through our online consultation, Dr. Dong’s consultation website. We will answer your questions in a timely manner, develop an individualized treatment plan based on your condition as much as possible, and provide the next step of treatment. Its management is similar to that of myasthenia gravis. Myasthenia gravis associated with malignant tumors (typically small cell lung cancer) can improve or disappear after successful treatment of the tumor and recurs with tumor recurrence. Pyridostigmine may lead to symptomatic improvement, and oral 3,4-diaminopyridine increased to 100 mg/d is more effective, although it can cause terminal and perioral sensory abnormalities (the two drugs can be combined). Immunosuppressive therapy is very similar to that of the systemic form of myasthenia gravis. 1) Nisolone: – Start orally at 1.5 mg/kg every other day or 100 mg every other day, whichever dose is lower – taper to find a smaller dose that controls symptoms 2) Azathioprine – best avoided in small cell lung cancer because of its slow onset of action Associated myasthenia gravis – for non-cancer patients, 2.5 mg/kg/day for severe myasthenia gravis. 3) Other immunosuppressants: – For myasthenia gravis, other drugs may work faster than azathioprine, so are more often used for tumor-associated disease. 4) Intravenous immunoglobulin and plasma exchange are available when severe weakness is present, but are less effective than in myasthenia gravis.