Salivary Gland Adenocarcinoma

Saliva contains many useful enzymes that help in the digestive process. These enzymes increase solubility of food by lubricating the contents. There are four major salivary glands, including the mandibular, sublingual, parotid, and zygomatic gland. Adenocarcinoma can affect any of these salivary glands in cats, but the major target of this tumor in cats is the parotid gland, the largest of the salivary glands. Adenocarcinoma of the salivary gland is highly metastatic and can metastasize into distant organs and tissues in the body. Siamese cats are at higher risk as compared to other breeds, and male cats are affected twice as much as compared to female cats. Like other adenocarcinomas, adenocarcinoma of the salivary glands usually affects cats older than eight years.

Symptoms and Types

Symptoms of adenocarcinoma of the salivary glands depends upon the type of salivary gland that is affected. Following are a few of the common symptoms related to salivary gland adenocarcinoma:

• Painless swelling of the upper neck, ear base, or upper lip
• Halitosis (foul breath)
• Weight loss
• Poor appetite
• Dysphagia (difficulty in swallowing)
• Exophthalmos (bulging of the eye)
• Sneezing
• Dysphonia (hoarseness)

Causes

The exact cause is still unknown. This disease is classified as idiopathic.

Diagnosis

Your veterinarian will perform a thorough physical exam on your pet, taking into account the background history of symptoms. Blood tests, biochemical profiles and urinalysis will be performed, though results will often return as normal with this disease. Radiographs of affected areas and bones can reveal important information about the nature and extent of the problem. X-rays of other regions may also be performed to see if the tumor has metastasized into these regions of the body, and more refined procedures, like tissue biopsy, will help in establishing a confirmatory diagnosis.