Malignant Thymoma and Myasthenia Gravis

MUCH has been written concerning the relation of myasthenia gravis to the thymus. There are fewer articles, however, describing myasthenia gravis with thymoma, and fewer still on its relation to malignant thymoma. In 1942 only 5 such cases had been collected.1 Castleman and Norris2 stated that thymoma occurred in 10 to 15 per cent of cases of myasthenia gravis and that "if implantation connotes malignancy, then the thymoma may be carcinomatous in a very small percentage of cases (between 5–10%)." Most authors agree with this figure of the association of thymoma with myasthenia gravis3 4 5 6; in 1951 an estimated 130 . . .