Of the 50 or so cysts my Toby had removed, one was on the ear flap. The concern here was that bleeding might be an issue-We all know how those ears can bleed like a stuck pig from just a little nick. But no bleeding and we didn't even have to keep his ears wrapped. It was benign, typical basset type cyst but you don't know for sure unless it's biopsied. After having had a dog with a mast cell tumor, I would have a fine needle aspirate done on any cyst/lump as they are referred to as "The Great Imposter" because they can look like a benign tumor but be an aggressive cancer. See Mast Cell Tumors for additonal information. Not trying to scare you but insist on a biopsy if your vet is going to remove the lump or a fine needle aspiratet if he's going to watch and wait.
Keep us posted.
Keep us posted.