I am afraid I cannot give you anything that is back and white nor supported by concusive peer reviewed published data that will lead you to a personal decision. Uniqueness of each patient and their disease, (separate from staging) are involved in this decision making process, and no one that I talked with indicated that any absolute rule applies.

Brian, stage 4 oral cancer survivor. OCF Founder and Director. The first responsibility of a leader is to define reality. The last is to say thank you. In between, the leader is a servant.