I was diagnosed in March 2018 with NETs in multiple locations after having a blockage in my small intestines. My first line of treatment was monthly injections of Octreotide. But when a GA 68 scan revealed some growth in April 2020, I had PRRT at Mayo in Phoenix from April-October 2021. The Mayo doctors explained at the time they had not determined when was the "best" time in the course of the disease to do this. I decided it was best to do it when I felt fairly healthy. I also understand it could be repeated. I do not consider it "the end of the line" for me. I personally would consider chemo more in that category - a personal choice.
There are procedures that specifically target NETS in the liver that I would encourage you to research and discuss with her doctors.