Strongly recommend you look at getting your sister on the Beck Protocol for cancer. I've seen severeal people cured of stage 1 to stage 3 cancers when they followed the protocol along with an alkalizing diet such as the Gerson Diet.
Chemo/Radiation are just methods of execution. No need to go there.
Besides the video in my post above, you may want to check out:
https://www.bobbeck.com/
https://www.cancertutor.com/bobbeck/
https://www.sota.com/sota-kits.html
If it's safe to get her home, it becomes easier to use therapies that have a better chance of working.
Once your sister gets to where she can drink things (like fruit juices or veg juices) safely, there is a good juice-based diet to go on called the Gerson Diet
https://gerson.org/gerpress/the-gerson-therapy/
It is geared to put as little strain on the liver as possible while getting sufficient nutrients into the body to build back the immune system and fight the cancer. When you couple it with blood electrification, it works very well.