Hello. Thanks for writing in. My name is***** and I would be happy to help you. If the entire side of the face is swollen, then it is most likely a tumor. But, I would definitely want to confirm that diagnosis. An abscess is less likely but still possible. I would expect an abscess to be more painful, and you may see puss drain from the mouth or from an opening in the side of the face once it opens. If it is inside the mouth, then it should be easy to visualize if he lets you look into the mouth. If he won't, it may help to give him a little sedative to take a look or even put a needle into the swelling and take an aspirate to evaluate for cancer. I think it is definitely worth a second opinion. A steroid injection should help with the inflammation and swelling, but it most likely won't shrink the tumor, unless it is something like lymphoma. Even then, it wouldn't shrink it or control it for long. A steroid should help for pain control, but if you feel like he is still in pain, then I would get a pain injection. If he is in pain, he may not eat or be reluctant for you to touch around his face. If it is cancer, his survival time can vary depending on the type of tumor it is. If it has been growing rapidly, it may only be a couple weeks to a couple months. If it has been slow growing, and he continues to eat, then a few months is not out of the question. It is just impossible to predict, though, without knowing what type of tumor you are dealing with. Please let me know if you have any other questions or concerns. Hope this helps.
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