x2. both mom and dad are vets. worked at moms vet clinic from the time i was 14 until i was 22. if it appeared in less than a week i seriously doubt it's a tumor. the vet will just drain it and put it on antibiotics. saw this kind of stuff all the time with outside cats. scratches and bites from other cats will cause an abscess quicker than anything. nasty stuff. no need to be put down though. lol