First, let me say that there really are wonderful treatments for cancer now and she may do beautifully with the surgery and treatments and ya'll may have many more wonderful years together.
Now...having said that, I feel that I should encourage you and everyone else to spend as much time as you can with your parents while they are here. Ask questions...learn all you can about them and for goodness sake, bury any hatchets that need to be buried because when they are gone, they are gone. I lost my father in July and had been caring for him for 2 years so that loss was no surprise and I had loads of time with him. Unfortunately, I didn't spend as much time with my mom while I was caring for him (they are divorced and she lives in Texas) and so when I got the call that she was ill, it NEVER even dawned on me that I would lose her. I found out she was sick on like Dec. 2nd, flew down and the 4th and she passed away on the 5th. Just like that....during the last half of 2010 both parents gone. Cherish every moment you have. I will be praying for you and your family.