Preheat oven to 350 degrees F. Grease a 3-quart baking dish; set aside. Cook pasta according to package directions; drain. Return to pan.
Meanwhile, in a large skillet, cook bacon over medium heat until crisp. Drain bacon on paper towels, reserving 2 tablespoons drippings in skillet. Crumble bacon; set aside. Add mushrooms and leeks to the reserved drippings; cook about 5 minutes or until tender.
Stir crumbled bacon, mushroom mixture, lobster meat, Gruyere cheese, half-and-half, blue cheese, truffle oil, and cayenne pepper into cooked pasta. Transfer mixture to the prepared baking dish.
Bake, covered, for 20 minutes. Stir gently. In a small bowl, combine bread crumbs and melted butter; sprinkle over pasta mixture. Bake, uncovered, for 10 to 15 minutes more or until mixture is heated through and crumbs are lightly browned. Let stand for 10 minutes before serving.