A case report of post-thymectomy myasthenia gravis with residual thymoma.

A forty-nine-year-old female patient, complaining of swallowing difficulties and general fatigue, was admitted to the first hospital of Nippon Medical School. At the age of 32, she was operated on for the removal of a well encapsulated non-invasive thymoma. Since then, she had been well till the age of 46, when chest X-ray films showed a recurrent thymoma which was excised together with the complete thymic tissues. One year later, she developed myasthenia gravis (MG) with a ptotic right upper eyelid and general fatigue. Subsequently, she was placed on medication. After 21 months, however, she died of myasthenic crisis in spite of vigorous respiratory and nutritional support. The autopsy revealed a small residual thymoma on the left lung, and systemic atrophy of the skeletal muscles. In this paper, the mechanism of post-thymectomy MG and the recurrence of non-invasive thymoma are discussed.