My Dad had Hodgkins Lymphoma in his late 20's in the 70's, they were able to treat it with radiation and chemo and it never returned.
A good friend of mine was diagnosed around age 24 right after graduating from BYU 4-5 years ago and was able to treat it with Chemo and is back to living a full/normal cancer-free life.
Most recently, a boy in my ward (23) was diagnosed with Stage 4 Hodgkin's Lymphoma. He went public with his diagnosis in Nov 2020 and after 4 treatments all signs of cancer on his scans are gone as of Feb 2021. He still has to complete the rest of his 7 treatments to make sure all of the cancer is gone, but it's all good news right now.
It's still so scary to face - prayers for her and your family.. and a few extra prayers for her doctors to know what to do as well!