Heat a small nonstick skillet over medium-high heat. Sprinkle tuna with pepper. Coat pan with cooking spray. Add tuna to pan, and cook 3 minutes on each side or until desired degree of doneness. Keep warm.
Combine tomato and next 7 ingredients (through juice) in a large bowl. Add pasta; toss to combine. Arrange about 1 1/3 cups pasta mixture on each of 3 plates. Flake fish with a fork; divide evenly over pasta. Sprinkle each serving with 2 tablespoons cheese.