I was diagnosed in Dec. 2024 and had 14 treatments ( 7 sessions of 2 weeks on, one week off) of Gemcitabine/Abraxane. I lost my hair, was very weak and tired and have minimal neuropathy in my feet, but tolerated it. The size of the tumor did not change but there may have been some killing of internal cells, possible necrotic tissue internally. I am also on Nivolumab immunotherapy for lung cancer, no mets from either. I was hoping to be a candidate for Whipple surgery, but my tumor was 4.2 x 4.8 cm. and needed to shrink away from a major vein and artery and reduce in size. The chemo did not accomplish that BUT I underwent 5 SBRT radiation treatments in September and it looks like it may have worked ( haven't spoken to the surgeon yet, just reading radiology report). I had the radiation done without using markers in order to be eligible for Nano-knife procedure. It's a relatively new procedure that not all hospitals have. I'm receiving treatment at CPMC San Francisco and as of last year has done more than 100 of them. It doesn't have a lot of history as far as survival rates, but the Whipple sounded pretty awful and the survival rates weren't great.
I am 78 years old and have been through 4 different cancers in 19 years. Hope your dad has good results. Oh, the oncologist and surgeon didn't think that another chemo drug would be effective hence the move to radiation. So far so good. Hope your dad has good results. Every one is different and reacts differently too.