My own pasta sauce using canned tuna is:
 
 4 cloves garlic, chopped
 4-5 dried red chili peppers, broken up
 4 anchovies
 evoo
 1 can Italian tomatoes
 12 chopped kalamata or other brine-cured olives, pitted and minced
 1 can tuna (preferably packed in oil), drained
 2 tablespoons minced fresh Italian parsley
 penne rigate
 
 1) Put some olive oil and the peppers in a pan and heat. When the oil
 is hot, put in the garlic and sautee for a minute or so -- not too
 long.
 2) Off the fire, put in the anchovies and mash them with a fork,
 stirring them around until they dissolve. Don't worry, if you think you
 hate anchovies, you'll discover that these'll just lend a wonderful
 background taste and you won't notice. But they are essential.
 3) Returnt to the fire, add the tomatoes and the chopped olives, bring
 to a boil, lower heat and cook over very low heat for about 20
 minutes. 
 4) After that, about the time you put the pasta in the pot, add the
 tuna, breaking it up with a fork and integrating it into the sauce. 
 5) Stir with the cooked pasta, adding the parsley. DO NOT USE CHEESE.
 Never. Not with fish. (Well, there are exceptions). 
 
 Serves 2 generously.