Make the tartar sauce: Mix the mayonnaise, pickles, scallions, parsley, lemon juice, mustard, Worcestershire sauce and hot sauce in a medium bowl until combined. Cover and refrigerate 30 minutes to blend the flavors.
Meanwhile, make the crab cakes: Mix the mayonnaise, parsley, mustard, lemon juice and Old Bay in a large bowl until combined. Add the panko and mix again. Add the crab and mix, taking care not to crush the meat. Shape the crab mixture into 8 patties, each about 3 inches in diameter. Cover and refrigerate 15 to 30 minutes.
Preheat the oven to 200 degrees F. Line a large baking sheet with a brown paper bag or a double layer of paper towels. Pour enough vegetable oil into a large skillet to come 1/2 inch up the side and heat over medium-high heat until the oil is hot but not smoking. Add the crab cakes in batches and cook until the undersides are golden brown, about 2 minutes. Flip the cakes and continue cooking until golden, about 2 more minutes. Transfer the crab cakes to the lined baking sheet and keep them warm in the oven while cooking the remaining cakes. Serve hot with the tartar sauce and lemon wedges.