Abstract
A 8-year-old male Akita was examined because of weakness and tachypnea of 2 months' duration. Digital percussion and concurrent auscultation of the cranioventral thoracic area revealed dull, nonresonant sounds. Thoracic radiography revealed a large, soft-tissue density encompassing the entire left cranial cuadrant of the thorax. Based on location, radiographic appearance, and the lymphoid cells found on cytologic examination of the mass, thymoma was considered as a temporary diagnosis.
Thoracotomy was performed through the 4th and 5th intercostal space. A 11 by 17 by 7 cm lobulated mass was excised from the anterior mediastinum. Light microscopic examination of the mass revealed thymic tissue with capsular and vascular invasion by lymphocytes. The findings were consistent with thymoma. No metastasis was noted at the surgery. The surgical recovery was uneventful and clinical weakness improved without medical therapy. At 24 months after the surgery, the dog has not shown recurrence of thymoma without any clinical signs.
