Effects of Solar Dermatitis
The skin is usually most effected in areas of the body which are sensitive to burning heat from the sun. Cats that are predominately white in color, or have white spots about their bodies, will be more likely to be effected. The reason for this is that there is no melanin, or colored pigment, to protect the skin from the sun. Any area of your cat's body can be affected, but dermatitis usually occurs around the ears; although the nose and eyelids are susceptible, as well.
When your cat has been exposed to the sun for a long period of time, the first thing you will probably notice is a reddening of the skin. The affected area will look scaly and there may be some hair loss, as well. Over time the lesions will begin to crust and appear as though they are infected.
The affected areas of skin are not usually painful. However, once they have been touched by solar dermatitis, they become more vulnerable under continued solar exposure. The lesions may begin to flake and peel and appear as infected scabs.
Methods of Treatment
Solar dermatitis can usually be treated by a combination of antibiotics and limiting exposure to the sun. Treatment will always depend on the severity of the burns and which areas of your cat's body have been affected. When the burns are very severe, a steroid cream can be prescribed.
Squamous Cell Carcinoma
If dermatitis is not treated and exposure to the sun continues, the lesions usually develop into skin cancer, or squamous cell carcinoma. You may initially notice the scabs, redness or hair loss on the affected areas of your cat, but there is no way for a cat owner to know if the condition has progressed to cancer. The only way to determine if the conversion has occurred is to have the affected areas biopsied and examined under microscope.
If the condition is determined to be squamous cell carcinoma, the best treatment option is surgery. During surgery, the skin that has been affected will typically be removed, along with any other questionable areas around it. However, if the nose or mouth area has been affected, surgery is not a good choice because of the delicacy of the area. In that case, radiation may be more appropriate.
The prognosis of surgical treatment is excellent and usually does not encounter any complications. Because squamous cell carcinoma is self-limiting, there is very little likelihood that the cancer will spread to any other part of the body.
Methods of Prevention
The best way to prevent solar dermatitis or the development of squamous cell carcinoma is to limit the exposure that your cat has to sunlight. You don't want to deprive your cat of sunlight altogether, but you do want to limit his exposure over long periods of time and when the sun is at its hottest point; such as around noon time.