I haven't fully converted this to the lowest WW pts yet, but here's my basic recipe for a tasty, fast and easy tuna pizza.
1/4 -1/2 c. prepared tuna
grated cheese (to cover, to your tastes)
Spread the tuna over the pita, like you would sauce on a pizza, and sprinkle with as much cheese as you like.
I cook mine in my little toaster over on broil, but it could also be done in the oven that way.