Tuna Noodle Casserole

8 oz. egg noodles
2 cans tuna (drained)
1 1/2 cups sour cream
3/4 cup milk
1 tsp salt
1/4 tsp pepper

Topping:
1/2 cup bread crumbs
1/2 cup parmesan cheese
4 tbsp melted margarine

Bake uncovered at 350 degrees for 35-40 mins