Microthymoma in elderly-onset myasthenia gravis detected preoperatively. (October 2016)

• Record Type: Journal Article
• Authors: Hino, Haruaki; Nishimura, Takashi; Seki, Atsuko; Nitadori, Jun-ichi; Arai, Tomio; Nakajima, Jun
• Is Part Of: Asian cardiovascular & thoracic annals. Volume 24:Number 8(2016)
• Page Start: 818
• Page End: 821
• Publication Date: 2016-10
• Subjects: Aging -- Mediastinal cyst -- Myasthenia gravis -- Thymectomy -- Thymoma -- Thymus neoplasms; Heart -- Diseases -- Asia -- Periodicals; Heart -- Diseases -- Pacific Area -- Periodicals; Heart -- Diseases -- Periodicals; Heart -- Surgery -- Asia -- Periodicals; Heart -- Surgery -- Pacific Area -- Periodicals; Heart -- Surgery -- Periodicals; Chest -- Surgery -- Asia -- Periodicals; Chest -- Surgery -- Pacific Area -- Periodicals; Chest -- Surgery -- Periodicals; 617.412
• DOI: 10.1177/0218492316665057
• Languages: English
• ISSNs: 0218-4923

Abstract

A 77-year-old woman with a 3-month history of muscle weakness was diagnosed with elderly-onset generalized myasthenia gravis (Myasthenia Gravis Foundation of America classification IIa) based on a high serum acetylcholine receptor antibody level (25.4 nmol·L −1 ) and neurological findings. Computed tomography detected a small nodule (diameter 15 mm) in the anterior mediastinum, which was suspected to be a thymoma. An extended thymectomy was performed. The pathological examination revealed a 6-mm-diameter thymoma, termed a microthymoma, accompanied with a unilocular thymic cyst without capsule formation (type B2 according to the World Health Organization classification). Some fat tissue was also found within the tumor.