My oncs have always used the term from the moment of diagnosis. I look at it this way being cancer free and being a survivor are two different criteria. My doctor says 5 years out from last clean scan is cancer free, and considered a "safe area" to say cancer free. I haven't made it there yet everytime I get close to a clean scan something else pops up.
So I go with Survivor! Any person who endures day in and day out this battle of cancer that attacks us both emotionally and physically is a Survivor whether your are family, friend, caregiver, or cancer patient or cancer free!
Your a Survivor!!!!