Place oven rack in topmost position and preheat oven to broil.
Drain the canned salmon of all liquid. Mix together the salmon, wasabi, mayonnaise, pickles, and tomatoes. Open the rolls and lay out on a baking sheet. Spoon 1/2 cup of the salmon mixture onto the bottom of each roll. Place one slice of cheese on top of the salmon mixture and broil in the preheated oven until the cheese melts and the top sides of the rolls begins to brown.