Cook the pasta in a large saucepan of lightly salted boiling water for 10-12 minutes. Drain well in a colander. Place the pasta in a large mixing bowl and toss well with the olive oil.
Drain the tuna and use a fork to roughly break it into flakes. Put the tuna into a blender or food processor. Add the lemon juice to taste, capers or wine vinegar and mayonnaise then blend together until smooth and creamy. Add to the pasta and stir together until all the ingredients are evenly mixed.
De-seed the capsicum and then finely dice. Finely dice the cucumber without removing the skin.
Add the capsicum, cucumber and corn kernels to the pasta and toss together. Spoon into a serving dish.
Remove the shell from the hard boiled eggs and cut into quarters. Arrange the wedges decoratively over the salad then serve.