The non-pigmented noses and white ear margins of cats are susceptible to repeated sunburn. Solar dermatitis refers to inflammation of the skin due to sun exposure. With time and repeated episodes of solar dermatitis, the cells undergo changes which eventually lead to cancer, known as squamous cell carcinoma (SCC).

How can I tell if my cat has SCC?

Solar dermatitis and squamous cell carcinoma can be indistinguishable to the naked eye. They usually start as spots or dots on the nose or on the ear margins, which can become slightly raised like a scab, or red and ulcerative. Many of these lesions are dismissed as scratches or wounds from fights, but if they don’t heal in a week or so, consult your veterinarian. Most cases occur in middle-aged to older cats, especially white cats.

How is SCC diagnosed?

As squamous cell carcinoma progresses, it eats away the surface of the nose and can cause snuffliness and sneezing. The lesion may irritate the cat so that it rubs its nose, causing it to bleed and become infected. Once SCC is at this stage it can be diagnosed by appearance.

However, early lesions need to be biopsied to confirm the diagnosis. This involves a small amount of tissue being removed by your veterinarian and sent to a laboratory to be analysed by a pathologist.

How is SCC treated?

The best treatment for squamous cell carcinoma is surgery to remove the affected area. Of course, surgery is limited by the size and extent of the affected area. Radiation and chemotherapy may also be recommended by your veterinarian.

Can SCC be prevented?

Keeping a white cat (or any cat) out of the sun as much as possible, especially during the hottest part of the day, is the only sure way to prevent SCC.

There are several sunscreens available that have been formulated for use on animals. The use of these may help in the prevention of sunburn, solar dermatitis and eventual squamous cell carcinoma.