Dear Christopher Cat
My cat Patch, whose face is mostly white, naps in a sunny window all day. I read your column about the need to apply sunscreen to dogs before their walks, and I’m concerned about Patch. Does the window glass protect her from ultraviolet rays and skin cancer, or should I apply sunscreen to her face?
You’re right to be concerned. Ultraviolet radiation can cause skin cancer in us cats, just as it can in dogs and humans.
Window glass blocks UVB rays, but not UVA rays, which penetrate deeply into the skin.
It sounds like Patch is exposed for prolonged periods, so her risk of skin cancer, particularly squamous cell carcinoma, is significant.
When we cats develop skin cancer, it’s often on our ears, nose and other areas where hair is sparse. Pink and other lightly-pigmented skin is most vulnerable.
To protect Patch, apply pet sunscreen to those areas, install UV-blocking film on the window, or close the curtain on her sunbathing.