Well, just got off the phone with the vet, she confirmed lymphoma. Given her age and other medical issues we don't plan to aggressively treat (radi/chemo) but are evaluating our options. For now she suggests staying on the Rimadyl, and adding Ultram when she starts showing signs of pain. I mentioned the elevated ALT but she said at 162, she's not that concerned and thinks keeping her comfortable is more of a prioritiy at this point.
Thank everyone for the well wishes.