Hi. You ask a complicated question. There are essentially 3 elements to consider when feeding a cat canned food that contains tuna (that is - canned food made for cats, not for humans). Thiamine, Vitamin E, & metals. As noted in the above article:
"If you’re feeding good quality commercial cat food manufactured by a reputable company, you can safely feed fish-based food without risking thiamine-deficiency or pansteatitis [Vitamin E deficiency]...At this point, it’s hard to tell whether heavy metals are a possible issue when feeding fish or fish-based products. With no established data as to the long-term effects, you may want to contact the manufacturer of your brand of cat food and ask if they test their product for heavy metals. Otherwise, consider limiting the consumption of fish-flavored products until more information becomes available on this topic."
These are the reasons why you hear so much about people limiting tuna (and, other fish) in their cat's diet. You also need to take into consideration how much tuna/fish is in the food compared to other proteins, the more non-tuna/non-fish proteins the less risk. So, you might be able to find some foods that still contain enough of the tuna 'flavoring' that would be amenable to your cat's palate, but have a higher quantity of non-fish based proteins included.