Concurrence of Myasthenia Gravis, Thymoma, and Thyroid Carcinoma

Abstract

Myasthenia gravis (MG) has been associated with disorders of the thyroid gland and the thymus, including thymoma, but not with thyroid cancer.¹ Rarely do tumors of both the thymus and thyroid glands coexist.^2-5 In the case reported herein, MG with thymoma appeared concurrently with papillary carcinoma of the thyroid. REPORT OF A CASE A 65-year-old woman had tolerated progressive dysphagia for two months before ptosis, diplopia, and weakness of her jaw and limbs forced her to seek medical attention. For one month she had been aware of a thyroid nodule. At age 58 years, endometrial adenocarcinoma had been successfully treated by total hysterectomy. She was overweight and mildly hypertensive. There had been neither previous thyroid disease nor irradiation of the neck. The diagnosis of MG (Osserman grade III) was established on the basis of abnormal fatigability and muscular weakness, which transiently improved after intravenous administration of edrophonium