Human marketed tuna can be bad for a cat. For one thing, it doesn't include taurine which a lack of can cause cats to go blind (which is why a diet of dog food for cats is bad, they don't include taurine). It doesn't have enough vitamin E, which can lead to all kinds of problems when combined with the fats in tuna.

Chicken of the Sea and others is fine for a cat as a treat occasionally, but you should really feed your cat tuna-flavored wet food instead of people food.