We present a rare case of thymoma in a 36-year old woman, who was initially diagnosed with severe myasthenia gravis and subsequently undergone surgical resection. During surgery tumor was found at the anterior mediastinum, tightly attached to the phrenic nerve, pleura and pericardium. Histological assessment showed large areas of sclerosis and fibrous collagenous tissue as well as islands of epithelial and lymphoid cells. Sclerosing thymoma, which is a rare subtype of thymoma (< 1%), was diagnosed, thus confirming the first report in Brazil. The patient showed partial improvement of symptoms associated with myasthenia gravis.
Thymoma; Sclerosis; Myasthenia gravis
