Metastatic malignant mesothelioma in a tiger (Panthera tigris)

An 8-yr-old female tiger (Panthera tigris) died following a 2-wk history of progressive depression, anorexia, respiratory insufficiency, and exercise intolerance. At the time of necropsy, numerous coalescing, 4-20-mm, tan, firm nodules were scattered throughout the pleural surfaces of the thoracic wall and the mediastinum, giving a velvety appearance to these surfaces. Histologically, the nodules were diagnosed as malignant pleural mesothelioma. Secondary metastasis to the regional tracheobronchial and mediastinal lymph nodes was observed.