I have now met many people who have had the whipple surgery as far back as 10 years plus! It was curative for them. Everyone’s case is different, but be joyous that it was found early. All surgery in the GI area will require some recuperation time and possibly a diet change, but a small price to pay! One help I might offer is to try to have your Dad as healthy as possible prior to the surgery. Good muscle tone, and healthy diet. ESP. Enough protein ( not just from red meat!). So happy it was found early. That is a rare occurrence! Many blessings,