With estrogen driven, it is best to use a 3:1 ratio of CBD to THC. Has she used it as of yet? There is a workup chart, but if she is used to it, work up as quickly as possible. Cut out sugar and any known inflammatory type foods, cancer feeds on mucus. Cut out red meats, and eat fruits and veggies known to fight cancer.
When using the oil if on BP Meds, must be monitored the oil naturally reduces BP, and some have to stop using pharma meds for BP when on the oil.
Drink plenty of water, the oil can dehydrate. Drinking water with fresh lemon and green tea are good choices.
Add in the enzyme Serrapeptase, it cuts mucus and helps rid the body of dying cells which keeps the kidneys from being over-taxed.
Here is a recommended workup chart, if she has never used I recommend following it. The first few days that is half the size of a grain of rice, and the other days are a full grain of rice. Some people will dose it out on parchment paper and put it in the freezer. She can do double duty and use it as a suppository and orally. The oil taste horrid, she can put it in PB, or use a capsule.
The oil is for life, you can not stop using it, or cancer does come back. This is very scary, my heart goes out to you, I think she will be fine with you in her corner. If you have any questions I might be able to help, just ask.
Big Hugs, my mothers side almost all died of cancer, both my sisters and my mother, I was not into cannabis so could not save two of them, I sure wish it was known at that time. My prayers go out to you both.