Myasthenia gravis associated with invasive malignant thymoma: two case reports and a review of the literature

INTRODUCTION: Approximately ten to fifteen percent of patients with myasthenia gravis are found to have a thymoma, and twenty to twenty-five percent of patients with thymoma have myasthenia gravis. Thymomatous myasthenia gravis tends to have a difficult clinical course and poor prognosis. CASE PRESENTATION: We report two cases (one patient of Asian ethnicity and the other of Caucasian ethnicity) of atypical presentations of myasthenia gravis associated with invasive malignant thymoma. Both patients were diagnosed at a young age, in their 20s. They presented with a turbulent course of myasthenia gravis and recurrent thymoma, but obtained good outcome after aggressive treatment involving multiple different specialists. CONCLUSIONS: Although thymomatous myasthenia gravis tends to have a difficult clinical course and poor prognosis, early and aggressive treatment along with multidisciplinary management may improve the outcome of these patients.