Squamous cell carcinomas (SCC) are one of the most common and dangerous skin cancers in cats – especially cats with white ears and non-pigmented noses. The most common initiating cause of SCCs in both cats and dogs is sun exposure. The usual sites for this cancer are the tip of the nose, eyelids, lips and ear tips. It’s essential – as with white-skinned dogs – that cats with white noses, faces and ears are kept inside or, at the very least, allowed only minimal time in the sun.
SCCs in cats become invasive quickly and it's really important this skin cancer is diagnosed and treated promptly.
Any crusty or bleeding sore that doesn't heal, especially if it's located in areas where the cat's fur is white or light coloured, is potentially a squamous cell carcinomas. This is the time to take your cat to the vet (even better, as soon as you notice a lesion in these white-haired vulnerable places). Tips of white ears can develop red, crusted and bleeding sores along the edges. If the sores are left to get larger, the ear tips will gradually disappear as the cancer erodes the tissues and the ear(s) will become increasingly malformed.
Early treatment includes surgery and/or cryosurgery (freezing), while more advanced cases require radiation or chemotherapy and have a poor prognosis. If the ear tips are affected, surgery to remove all the ulcerated tissue is usually effective - your cat may have a different appearance, but it will recover well.
Limit the amount of time your cat spends in the sun. If your cat spends a lot of time on the window sill during the day, a window shade or reflector to block UV rays is a sensible option. It's not out of the question to apply sunscreen to your cat's ears and nose before it goes out in the sun, or tattoos can be applied as a permanent sunscreen.