Thymoma is a rare tumor originating from the thymic epithelium, typically located in the anterior mediastinum. Ectopic thymomas are extremely uncommon and may occur in the neck, middle or posterior mediastinum, lung, or pleura. We report the case of a 62-year-old woman presenting with cough, weight loss, and asthenia. Chest computed tomography (CT) revealed a right pleural mass. Complete surgical resection was performed, and the postoperative diagnosis confirmed a WHO Type AB thymoma, classified as Masaoka-Koga stage IIa. Following surgery, she underwent adjuvant radiotherapy, and no recurrence was observed during follow-up.
Keywords: Ectopic mass; Myasthenia gravis; Pleura; Thymoma.
© 2025 The Authors. Published by Elsevier Inc. on behalf of University of Washington.