I am so sorry to hear your news.
I would certainly put her on a cancer diet and supplements. If you can get IP6 there, I would add that, it can be used with chemotherapy.
I would think long and hard about chemotherapy. It can be a lifesaver, but I would want to know about success rates, etc. There are probably only limited circumstances under which I would have a pet undergo chemo, and I don't know enough about your situation.
Some of these links might be helpful: