Soak bread in milk for five minutes,then squeeze out milk. Cut tuna into small cubes. Lightly mix bread with tuna,parmesan,two tablespoons chopped parsley,lemon zest,egg,sea salt and pepper,and form into 12 medium-sized meatballs.
Heat oil in a pan and cook meatballs over medium heat for five minutes until golden all over.
To make sauce,combine cherry tomatoes,garlic,raisins,olive oil,two tablespoons chopped parsley,sugar,sea salt and pepper in a large fry pan. Add a dash of water and simmer for 15 minutes,stirring occasionally. Add meatballs and simmer for 10 minutes until cooked through.
Cook pasta in simmering salted water until al dente and drain. Divide between four warm pasta plates and top with tuna meatballs and sauce. Scatter with remaining parsley and pine nuts.