knot on boxers face

Question
about two weeks ago my boxer developed a knot on her face about the size of a dime. It literally appeared almost overnight. By the time we returned from vacation it was very swollen. I took her to a vet who gave her an injection of steroids and antibiotic. Within a day the knot went down to its original size. Now, it appears it is getting big again. Could this be a cyst?

Answer
No-- cysts grow and never shrink or go away. They have to be removed.

At first I thought she was stung or bitten- but to go down then re-swell is odd.

I don't know what that could be or what caused it as the steroids and antibiotics should have reduced it and then it would go away--

Take her back to the vet and explain it swelled up again-- further diagnosis is needed.