Multiple Thymoma with Myasthenia Gravis

The actual incidence of multiple thymoma is unknown and rarely reported because it remains controversial whether the cases represent a disease of multicentric origin or a disease resulting from intrathymic metastasis. In this case, a patient underwent total thymectomy for multiple thymoma with myasthenia gravis via bilateral video-assisted thoracic surgery. A well-encapsulated multinodular cystic mass, measuring 57 mm×50 mm×22 mm in the right lobe of the thymus, and a well-encapsulated mass, measuring 32 mm×15 mm×14 mm in the left lobe, were found. Both tumors were type B2 thymoma. Few cases of multiple thymoma with myasthenia gravis have ever been reported in the literature. We report a case of synchronous multiple thymoma associated with myasthenia gravis.