Line a baking sheet with aluminum foil for easy clean-up.
Combine the eggs, mayonnaise, Dijon mustard, Worcestershire, Old Bay, salt, celery, and parsley in a large bowl and mix well. Add the crab meat (be sure to check the meat for any hard and sharp cartilage) and panko; using a rubber spatula, gently fold the mixture together until just combined, being careful not to shred the crab meat. Shape into 6 cakes (each about ½ cup) and place on the prepared baking sheet. Cover and refrigerate for at least 1 hour. This helps them set.
Preheat a large nonstick pan over medium heat and coat with oil. When the oil is hot, place the crab cakes in the pan and cook until golden brown, 3 to 5 minutes per side. Be careful as oil may splatter. Serve the crab cakes warm with the tartar sauce.
In a small bowl, whisk together the mayonnaise, relish, mustard, onion, and lemon juice. Season with salt and pepper, to taste. Cover and chill until ready to serve.
Make-Ahead Instructions: The crab cakes can be formed, covered, and refrigerated a day ahead of time before cooking. The tartar sauce can be made and refrigerated up to 2 days in advance.
Note: If you can only find jumbo lump crab meat, you may need to break the pieces up a bit. If the clumps are too large, the crab cakes won't hold together well.
Note: The nutritional information does not include the tartar sauce.