Oncocytoma in Cats
Oncocytoma is an extremely rare and benign tumor in cats. This type of tumor involves atypical cells found in the endocrine glands and epithelium (the tissue lining the cavities of the body). Endocrine glands are responsible for secreting hormones directly into the blood and lymph nodes.
As a benign tumor, an oncocytoma does not metastasize, and also tends to be minimally invasive. Concern arises according the location of the tumor, as its presence may restrict movement, blood passages, or airways. Though this is rare in cats, when it does occur, the tumor is commonly found in the area of the larynx. However, the tumor is also commonly found around the kidney, and can occur wherever there are endocrine glands and epithelium.
Symptoms and Types
Symptoms depend on the location of the tumor mass. In some patients difficult breathing and change in voice may be seen.
The cause for this disease is unknown.
You will need to give a detailed medical history to your veterinarian, including background symptoms, time of onset, and the frequency of the symptoms. One of the main indications is a change in your cat's tone of voice. Your veterinarian will perform a detailed examination of your cat's larynx – the area of the voice box. Standard laboratory tests will include a complete blood count, biochemistry profile, and urinalysis. The results of these tests are usually normal unless a concurrent disease is present.
If it is indicated, your veterinarian will also take x-rays of larynx and lungs to see if there is any metastasis, which would indicate a different type of tumor. For a more detailed examination, your cat will be lightly sedated and your veterinarian will examine the larynx internally using a laryngoscope (a tubular diagnostic tool that is inserted into the laryngopharynx). During this procedure, your veterinarian will take a sample of tissue from the mass and send it to a veterinary pathologist for evaluation. The biopsy sample should enable your veterinarian to establish a definitive diagnosis.
After a concrete diagnosis has been made, your veterinarian will schedule surgery to remove the tumor mass from the larynx area. During surgery, maximum care and efforts will be directed towards saving the larynx functions.
Living and Management
After a surgical resection of the tumor mass has been performed, the overall prognosis for most patients is excellent. After a complete resection, a cure is usually achieved in affected patients, as this tumor very seldom metastasizes. However, if a complete resection can not be achieved, you will need to watch your cat for any symptoms of a recurrence, which will require a second round of more aggressive surgery. Again, even with a partial resection, prognosis is generally excellent due to the benign nature of this tumor. Once surgery has been performed successfully, however, no follow-up will be required and your cat may go on to live a normal life.