Page 309 - Small Animal Internal Medicine, 6th Edition

CHAPTER 18 Disorders of the Larynx and Pharynx 281

LARYNGEAL NEOPLASIA Suggested Readings
Clarke DL, Holt DE, King LG. Partial resolution of hypoplastic
VetBooks.ir Neoplasms originating from the larynx are uncommon in trachea in six English bulldog puppies with bronchopneumonia.
dogs and cats. More commonly, tumors originating in tissues
J Am Anim Hosp Assoc. 2011;47:329.
adjacent to the larynx, such as thyroid carcinoma and lym-
young related Pyrenean mountain dogs. J Small Anim Pract.
phoma, compress or invade the larynx and distort normal Gabriel A, et al. Laryngeal paralysis-polyneuropathy complex in
laryngeal structures. Clinical signs of extrathoracic (upper) 2006;47:144.
airway obstruction result. Laryngeal tumors include carci- Jakubiak MJ, et al. Laryngeal, laryngotracheal, and tracheal masses
noma (squamous cell, undifferentiated, and adenocarci- in cats: 27 cases (1998-2003). J Am Anim Hosp Assoc. 2005;41:310.
noma), lymphoma, melanoma, mast cell tumors and other Lodato DL, et al. Brachycephalic airway syndrome: pathophysiol-
ogy and diagnosis. Compend Contin Educ Vet. 2012;34:E1.
sarcomas, and benign neoplasia. Lymphoma is the most Oechtering GU. Brachycephalic syndrome—new information on
common tumor in cats. an old congenital disease. Vet Focus. 2010;20:2.
Clinical Features Oechtering GU, et al. A novel approach to brachycephalic syn-
drome. 1. Evaluation of anatomical intranasal airway obstruc-
The clinical signs of laryngeal neoplasia are similar to those tion. Vet Surg. 2016;45:165.
of other laryngeal diseases and include noisy respiration, Poncet CM, et al. Prevalence of gastrointestinal tract lesions in 73
stridor, increased inspiratory efforts, cyanosis, syncope, and brachycephalic dogs with upper respiratory syndrome. J Small
a change in bark or meow. Mass lesions can also cause con- Anim Pract. 2005;46:273.
current dysphagia, aspiration pneumonia, or visible or pal- Riecks TW, et al. Surgical correction of brachycephalic airway syn-
pable masses in the ventral neck. drome in dogs: 62 cases (1991-2004). J Am Vet Med Assoc.
2007;230:1324.
Diagnosis Schachter S, et al. Laryngeal paralysis in cats: 16 cases (1990-1999).
J Am Vet Med Assoc. 2000;216:1100.
Extralaryngeal mass lesions are often identified by palpation Schuenemann R, Oechtering G. Inside the brachycephalic nose:
of the neck. Primary laryngeal tumors are rarely palpable conchal regrowth and mucosal contact points after laser-assisted
and are best identified by laryngoscopy. Laryngeal radio- turbinectomy. J Am Anim Hosp Assoc. 2014;50:237.
graphs, ultrasonography, or computed tomography can be Shelton DG. Acquired laryngeal paralysis in dogs: evidence accu-
useful in assessing the extent of disease. Differential diagno- mulating for a generalized neuromuscular disease. Vet Surg.
ses include obstructive laryngitis, nasopharyngeal polyp, 2010;39:137.
foreign body, traumatic granuloma, and abscess. Cytologic Stanley BJ, et al. Esophageal dysfunction in dogs with idiopathic
examination of fine-needle mass aspirates may provide a laryngeal paralysis: a controlled cohort study. Vet Surg.
diagnosis. Yield and safety are increased with ultrasound 2010;39:139.
guidance. A definitive diagnosis of neoplasia requires histo- Thieman KM, et al. Histopathological confirmation of polyneu-
ropathy in 11 dogs with laryngeal paralysis. J Am Anim Hosp
logic examination of a biopsy specimen of the mass. A diag- Assoc. 2010;46:161.
nosis of malignant neoplasia should not be made on the basis Thunberg B, et al. Evaluation of unilateral arytenoid lateralization
of gross appearance alone. for the treatment of laryngeal paralysis in 14 cats. J Am Anim
Hosp Assoc. 2010;46:418.
Treatment
Torrez CV, et al. Results of surgical correction of abnormalities
The therapy used depends on the type of tumor identified associated with brachycephalic airway syndrome in dogs in Aus-
histologically. Benign tumors should be excised surgically, if tralia. J Small Anim Pract. 2006;47:150.
possible. Complete surgical excision of malignant tumors is Wilson D, et al. Risk factors for the development of aspiration
rarely possible, although ventilation may be improved and pneumonia after unilateral arytenoid lateralization in dogs with
time may be gained to allow other treatments such as radia- laryngeal paralysis: 232 cases (1987-2012). J Am Vet Med Assoc.
tion or chemotherapy to become effective. Complete laryn- 2016;248:188.
gectomy and permanent tracheostomy may be considered in
select animals.

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