My doctor received pre-auth for a certain kind of radiation therapy for my post-op breast cancer but then changed it to a different kind without notifying me. My health care insurance eventually denied the claim as medically unnecessary (better options exist). Two internal appeals were not successful. If an external appeal will not be in my favor what else can I do in this situation? What sort of leverage do I have against the hospital/doctor (both the doctor and hospital are in-network)?