Five-Can Tuna Casserole

1 can tuna
1 small can evaporated milk
1 can chicken-rice soup
1 can mushroom soup
1 can chow mein noodles
1/2 cup Cheddar cheese, shredded
Water chestnuts, sliced (optional)

Combine all ingredients and pour into a greased casserole. Bake at 350 degrees F for 45 minutes.