Should my cousin's daughter amputate her other leg, which is afflicted with cancer and causing her severe pain, or should she leave it?

We ask God to reward the woman and her family for their affliction, and to grant them the recompense of those who are patient and seek their reward from God. For God Almighty has promised the patient a reward without measure. We have also learned that God has not sent down a disease except that He has sent down a cure for it, and the reference for determining treatment methods are skilled doctors, and all we have to do is seek God's help in the means of treatment.