Laryngeal neoplasia in dogs and cats

Neoplasms originating from the larynx are uncommon in dogs and cats. More commonly, tumors originating in tissues adjacent to the larynx, such as thyroid carcinoma and lymphoma, compress or invade the larynx and distort normal laryngeal structures. Clinical signs of extrathoracic (upper) airway obstruction result. Laryngeal tumors include carcinoma (squamous cell, undifferentiated, and adenocarcinoma), lymphoma, melanoma, mast cell tumors and other sarcomas, and benign neoplasia. Lymphoma is the most common tumor in cats.

The clinical signs of laryngeal neoplasia are similar to those of other laryngeal diseases and include noisy respiration, stridor, increased inspiratory efforts, cyanosis, syncope, and a change in bark or meow. Mass lesions can also cause concurrent dysphagia, aspiration pneumonia, or visible or palpable masses in the ventral neck.

Extralaryngeal mass lesions are often identified by palpation of the neck. Primary laryngeal tumors are rarely palpable and are best identified by laryngoscopy. Laryngeal radiographs, ultrasonography, or computed tomography can be useful in assessing the extent of the disease. Differential diagnoses include obstructing laryngitis, nasopharyngeal polyp, foreign body, traumatic granuloma, and abscess. For a definitive diagnosis of neoplasia to be made, histologic or cystologic examination of a biopsy specimen of the mass must be done. A diagnosis of malignant neoplasia should not be made on the basis of the gross appearance alone.

The therapy used depends on the type of tumor identified histologically. Bening tumors should be excised surgically if possible. Complete surgical excision of malignant tumors is rarely possible, although ventilation may be improved and time may be gained to allow other treatments such as irradiation or chemotherapy to become effective. Complete laryngectomy and permanent tracheostomy can be considered in select animals.

The prognosis in animals with bening tumors is excellent if the tumors can be totally resected. Malignant neoplasms are associated with a poor prognosis.

We would love to hear your pet's story. Please add a comment.