Squamous Cell Carcinoma in Cats: Skin, Ear and Mouth Cancer Explained

By Tailwisp Editorial TeamUpdated October 20, 20264 min read

A scab on the ear of a white cat may not seem like much. But when it keeps coming back, or never heals, it may be squamous cell carcinoma, one of the most common cancers in cats. Caught early, some forms can be treated successfully. Caught late, the outlook is far worse.

What is squamous cell carcinoma?

Squamous cells make up the surface layer of skin and the lining of the mouth and other organs. In SCC, these cells grow abnormally, forming tumors that invade deeper tissue. In cats, it appears in two main settings: on the skin, and in the mouth.

Skin SCC

• Where. Ear tips, eyelids, nose and lips, where there is little hair and pigment.
• Who. White and light-colored cats, particularly those that sunbathe. Chronic sun exposure damages skin cells over time.
• Progression. It often begins as actinic keratosis, a reddened, crusty patch, which may progress to a scabby ulcer that bleeds and does not heal. Cats may scratch or shake their heads.

See white cats and deafness and cat coat colors and patterns.

Oral SCC

• Where. Under the tongue, along the gums or the back of the mouth. It is the most common oral cancer in cats.
• Signs. Drooling, bad breath, bleeding from the mouth, difficulty eating, dropping food, weight loss, facial swelling and loose teeth.
• Risk. Linked with exposure to tobacco smoke, flea collars, canned tuna diets in some studies, and chronic inflammation. The exact cause is uncertain.

These signs can look like dental disease, so persistent mouth problems should be checked. See cat dental disease and gingivitis and stomatitis in cats.

Diagnosis

The vet examines the lesion, takes a sample by needle or biopsy, and may do bloodwork, chest X-rays and imaging such as CT to check for spread, especially for mouth tumors. Early biopsy is crucial.

Treatment

Skin

• Surgery, to remove the tumor, often including the ear tip, nose planum or eyelid, with a margin. Ear tip removal is generally well tolerated and often curative.
• Radiation, cryotherapy, laser or photodynamic therapy, for some small lesions.
• Topical or injected treatments, in selected cases.
• Chemotherapy, in some situations.

Oral

• Surgery, when possible, removing part of the jaw.
• Radiation, and chemotherapy.
• Palliative care, including pain relief, feeding tubes and anti-inflammatory drugs.

Oral SCC is often advanced at diagnosis, and survival may be short, from weeks to months, though some treatments extend it. Talk to your vet or an oncologist about goals. See cancer in cats and cat quality of life and saying goodbye.

Prevention

• Keep white and light-faced cats indoors, or out of strong midday sun. Close blinds, or use window film that blocks ultraviolet light.
• Ask your vet about pet-safe sunscreen. Never use human sunscreen with zinc oxide or salicylates, which are toxic when licked.
• Do not smoke around cats.
• Check ears, nose and eyelids monthly.
• Take any sore that does not heal in two weeks to the vet.
• Keep dental care up to date. See how to brush a cat's teeth.

Monthly check

Look at the tips of the ears, bridge of the nose and eyelids. Note redness, crusts, scabs, hair loss or sores. Take photos to compare.

Aftercare

After surgery, keep the cat comfortable, use a cone, give pain relief and return for rechecks. New lesions may appear, so keep monitoring.

Ear tip surgery in practice

Removing the tip of the ear, called a pinnectomy, sounds drastic, but cats usually heal well and look quite neat afterward. Surgery is done under anesthesia, with pain relief. The ear heals in a couple of weeks. For many cats with early SCC, this is curative. Without surgery, the tumor can spread across the ear and face, and become much harder to treat. See cat anesthesia safety.

Nose and eyelid lesions

Tumors on the nose and eyelids are harder to remove without affecting appearance and function. Options include radiation, freezing, laser, photodynamic therapy and sometimes surgery with reconstruction. A veterinary oncologist or surgeon can help select the best approach. Treat early, since small lesions are easier to manage.

Sun protection

Window film that filters ultraviolet light is a useful tool for sunbathing cats. Keep cats indoors during peak sun, and offer shaded perches. If you use sunscreen, ask your vet for a product that is safe if licked. Check your cat's skin regularly, particularly if it has white ear tips or a pink nose.

Living with the diagnosis

An SCC diagnosis is frightening, but many cats with skin SCC do well after treatment. For oral SCC, focus on comfort, pain relief, nutrition and time together. Your vet can help plan.

When to see a vet

See a vet for any sore that does not heal, or for mouth drooling or bleeding. Use the US vet directory to find a clinic.

This article is general educational information, not veterinary advice. Every cat is different. If your cat is unwell, or you are unsure about a symptom, diet change or medication, contact your veterinarian.