My 8 year old Cattle Dog Cookie has Lymphoma. Nothing they can do really but give her Steroids and a Chemo med in pill form so she lives the rest of her shortened life in comfort.
Whit, 6 months is forever to a dog - you are already working to make sure she is comfortable, just love her all you can while you have her. it's really all we can do anyway - we never know how much time we have with family.