We report two middle-aged women with thymic hyperplasia mimicking thymoma. A 46-year-old woman presenting with a cough was referred to our division for the diagnosis of a light diffuse interstitial shadow of the lung and a mass in the anterior mediastinum on a CT scan. A thymic specimen obtained by video-assisted thoracoscopic surgery showed lymphoid follicles. As we could not rule out a thymoma because she had no autoimune diseases, we performed a thymo-thymectomy through a median sternotomy. The final diagnosis was not thymoma but lymphofollicular thymic hyperplasia. The other patient was a 48-year-old woman who presented with precordial pain. A cystic lesion in the anterior mediastinum was found on chest CT and MRI. True thymic hyperplasia combined with a thymic cyst was diagnosed on thymo-thymectomy through a median sternotomy. Thymic hyperplasia without self-immunologic disorder or true thymic hyperplasia in middle-aged adults is extremely rare. However, this entity should be considered in cases showing an anterior mediastinal mass mimicking thymoma, even in aged patients.
収録刊行物
日本呼吸器外科学会雑誌 = The journal of the Japanese Association for Chest Surgery
日本呼吸器外科学会雑誌 = The journal of the Japanese Association for Chest Surgery 25(1), 64-68, 2011-01-15
