Ear Tumors in Cats

Felines can be affected by basal cell tumors, papilloma and inflammatory polyps, but ceruminous gland adenocarcinoma are the most common form of feline ear tumor. Often appearing as black or purple masses, ceruminous gland adenocarcinoma tumors more commonly affect felines between the ages of five to ten years of age. Felines affected by ear tumors may display clinical signs of itchiness, foul odor, pain and discharge from the ears, which can mimic the symptoms of other common feline ear conditions.

Ear tumors in cats are defined as abnormal cell growths within the structures lining or supporting the ear. An ear tumor could emerge from the outer layer of skin, the oil or earwax glands, bones, connective tissues, muscles or middle layers of the skin within a cat’s ear. 

The most obvious symptoms of ear tumors in cats is itching and pain of the ears. Polyps or lumps may be visible to the naked eye inside the ear canal, but can vary depending on location. These polyps may lacerate, leading to ear discharge or inner ear bleeding. Clinical signs of ear tumors in cats pet owners may note at home include the following: 

• Deafness
• Ear draining from an internal abscess
• Swelling 
• Ear scratching 
• Head shaking 
• Foul odor coming from the ear 
• Ear discharge 
• Bloody ears
• Pus-filled ears 
• Waxy buildup inside the ears

If the inner or middle ear is affected by an ear tumor, the feline may display neurological signs such as a head tilt and lose her coordination, or sense of balance. 

The exact cause of ear tumors in cats is unknown, however, these tumors are believed to be the result of long-term ear canal inflammation caused by chronic infection. It is thought that this chronic inflammation may lead to abnormal development and growth of the ear tissues, causing a tumor to form. This theory comes from the fact that episodes of inflammation cause the earwax gland to promote thick secretions in the external ear canal, which may stimulate cancerous cell production. 

Felines that have a history of chronic ear infections of yeast, bacteria or mites are at higher risk for developing an ear tumor. These infections lead to increased inflammation, causing an overgrowth of tissues and possible formation of cancerous growths.

Your veterinarian will likely base his/her definitive diagnosis upon physical and microscopic examination. Termed histopathology, a microscopic examination of the tissues will provide an accurate diagnosis to the nature of the feline ear tumor. The veterinarian or specialist will need to take a small sample of tissues from the tumor and send the specimens to a specialized diagnostic laboratory. Once at the lab, a veterinary pathologist will determine the nature of the cells, which will indicate whether or not the mass can be fully removed. 

Once the laboratory results are received, the veterinarian will  likely want to perform a urinalysis and blood work to obtain an idea of the feline’s overall health status. 

Your veterinarian might refer your feline to a board-certified surgical specialist. A veterinary surgeon is often recommended when handling feline ear tumors, canal tumors, and masses of the middle ear. The most common and effective way of treating ear tumors in cats is surgically removing the growth. However, in cases which the tumor has grown to surrounding tissues and the tumor alone cannot be removed without damaging the ear, extensive surgery is required to ablate the canal. Depending on your feline’s specific condition and the medical advancements available to you, laser surgery to remove the mass is also highly effective.

After surgery, you will be required to keep the surgical site clean and prevent your cat from interfering with healing time. Scratching or rubbing of the ears can cause the operation site to bleed or become infected, ulcerated, and inflamed, therefore, an Elizabethan collar will likely be sent home with you. Any manipulation of the site can remove sutures, which should be reported to your veterinarian immediately. Talk to your veterinarian if you have any questions about aftercare for your feline following surgery. 

In most ear tumor cases, surgical removal of the tumor results in a cure. A histopathology of the mass will give your veterinarian an idea of how your cat’s growth will behave, but the veterinary pathologist will state a prognosis of recurrence.