A diagnosis of PC can be terrifying.
The fact the doctors are confident they can attempt the Whipple surgery is actually a positive thing. Many cases of PC are found too late and surgery is not an option.
The Whipple surgery is difficult and recovery can be a real challenge for the patient. But it offers an opportunity for a possible cure. The surgeon should go over everything in as much detail as your Aunt wants (maybe has already) before surgery. It's a good idea for someone to be with her during appointments with the doctors to take notes. I was pretty much in a state of shock when I received the diagnosis, and was so thankful my Husband was at all appointments with me.
Hopefully, your Aunt is having surgery at a hospital experienced with doing Whipple surgery. It is important that the surgeon and surgical staff have experience with this surgery. It is complicated.
I had Whipple surgery over five years ago. I'm OK. I hope your Aunt has a positive outcome as well.