Lung Collapse and Rib Osteolysis Associated with Squamous Cell Carcinoma in a Cat
Squamous cell carcinoma (SCC) is the most common cutaneous tumor in the cat, and it mainly develops in the oral cavity or the skin surrounding the head.
The etiopathogenesis of SCC of the lung region is not fully known, and on previous reports, predilection for metastasis to the digits of pulmonary SCC was reported.
This case report describes clinical features and etiopathogenesis of feline pulmonary squamous cell carcinoma associated with lung, mediastinum metastasis and rib invasion.
A 4-year-old, castrated male Himalayan cat was presented for dyspnea and anorexia. The cat underwent thoracic radiographs, ultrasonography, fine-needle aspiration, computed tomography and histopathology.
Thoracic radiographs showed left-sided pleural effusion and after thoracocentesis of the exudate, lung collapse and pneumothorax were revealed. Ultrasonography revealed multiloculated pleural effusion. Computed tomography confirmed severe osteolysis in the left third rib region and irregularly thickened pleural wall. Fine-needle aspiration of the lesion revealed malignant epithelial cell clusters with polygonal to fusiform shape. Necropsy revealed left caudal lung lobe mass with metastasis throughout the entire lung lobe, mediastinum and the pleural wall. Upon histopathology, squamous cell carcinoma was confirmed in all the lesions.
In conclusion, this is the first case report describing clinical and etiopathological features of atelectasis and rib osteolysis resulting from pulmonary SCC.