Preoperative spontaneous regression of type B2 thymoma in a patient with myasthenia gravis

Abstract

Thymoma is the most common tumor of the anterior mediastinum. Spontaneous regression of thymoma is extremely rare. A 34-year-old female patient without any known disease, admitted by a myasthenic crisis, had a mass of 76 x 53 x 88 mm on thorax computed tomography (CT). The patient received intravenous immunoglobulin (IVIg) treatment for 5 days, pyridostigmine 60 mg/8 hours and prednisone 30 mg/day for the treatment of myasthenic crisis. Thorax CT on the 18th day showed that the mediastinal mass regressed to 63 x 30 x 63 mm. Histopathological analysis after extended thymectomy revealed the diagnosis of type B2 thymoma.