Tough but informed decision

I wondered if you know of anyone who has been in the same situation we sadly are with Izzy at the moment? She has been diagnosed with colitis and rectal carcinoma recently.
She is such a lovely girl and we really want to make the right decision for HER...not selfish for us and not taking into account finances, though may have to rob a bank! I wondered if anyone has been in the same situation? Surgery may be a possibility, though , it’s pretty major, and we have already been told the tumour will regrow. We’re soul searching as to what is kindest for Izzy. 
Anyone else's experiences/outcomes may help, We don't want to pit her through so much if her quality of life is not likely to improve, indeed may do the opposite if surgery is opted for, however we do want to give her the best option. 

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