Put it down to global warming or the hole in the ozone layer but sunny days are officially here to stay. Cases of human skin cancer are on the increase, so much so that there's a marked trend against the tan as the height of fashion.
Cats suffer the most from the increased ultraviolet rays that summer days bring.
It's the tips of their ears that catch the burn. To begin with, the tissues of the ear become sore and tender but if left untreated these early tissue changes progress to an unpleasant skin cancer, squamous carcinoma. Treatment can involve hormonal steroid administration to slow up the rate of tissue change or, at worst, amputation of the affected ear. So it is better by far to prevent the sun causing biological havoc by applying high factor sun block to the tips of the ears. It may sound odd but your cat will be grateful and it is a simple preventive measure that all owners of white cats or cats with white-tipped ears should consider.