What kind of prognosis did your doctor give you insofar as rate of progression?
I would personally never opt for mainstream treatment without first trying natural alternatives. Have you considered at least looking at what nature might have to offer?
My thinking is what will the harm be in trying an alternative for a month - and if there has been no spread or increase in the cancer, or even better, a decrease, then go another month. You may just go on until the cancer is gone and you have not only beaten the symptoms of cancer (the cancerous cells) but also the underlying causes.
Regardless of what you choose, I would highly, highly recommend a good natural cleansing and detox. Bentonite clay would be an excellent start. And there are some very good liver, bowel, gallbladder and kidney cleanses as well.
Good luck! Let me know if you want some information on natural alternatives. I have spent many years and tens of thousands of hours researching them.