Tumors of the Respiratory System

Condition Overview

Benign and malignant tumors occur in the larynx, trachea, bronchi, and lungs.

Symptoms

Laryngeal Tumors are uncommon and occur in middle-aged to older dogs. Most are malignant (squamous cell carcinomas). Signs are noisy breathing, change in voice, and loss of bark. A characteristic stridor may be heard when the dog inhales. Sudden death can occur from respiratory obstruction.

Tracheal Tumors are rare. In older dogs, they tend to be malignant (osteosarcomas). In young dogs, they are more likely to be benign (osteochondromas). The most common sign is a productive cough (producing material upon coughing). Stridor on inhalation may be noted during exercise or panting. Cyanosis and collapse can occur when the tumors get very large and cause severe respiratory obstruction.

Lung Tumors account for about 1% of all neoplasms in dogs. Most arise from cells lining the bronchi. They tend to occur in older dogs of both sexes. Lung tumors in dogs may be associated with exposure to cigarette smoke.

Most primary lung tumors are malignant ans will have already spread to other parts of the body by the time they are diagnosed. A harsh, non-productive cough is the most common sign. Pleural effusion may occur as a late complication.

Metastatic Lung Tumors are tumors that spread to the lungs from other parts of the body, and are more common than primary lung tumors. Tumors that metastasize to the lungs include mammary gland cancers, osteosarcomas, thyroid cancers, melanomas, and squamous cell carcinomas.

All symptoms +

Causes

Causes vary by the type of cancer.

Diagnosis

The diagnosis of laryngeal, tracheal, and lung tumors is based on chest X-rays, ultrasound, bronchoscopy and or transtracheal washings, and cytology. Tissue biopsy provides an accurate diagnosis and helps in planning treatment.

Treatment

Surgical exploration and removal of small tumors offers the best chance for cure. Larger tumors usually cannot be cured, but may respond to chemotherapy. The advanced age of many dogs with respiratory tract tumors usually makes aggressive treatment impractical.

Prevention

There is no prevention for these cancers, however, diets rich in antioxidants have shown promise in reducing the cell damaging effects of oxygen on cells. This damage is one precursor to mutated cell growth.. cancer.

Support

Please contact your veterinarian if you think your pet may have this condition.