Hi there and welcome. I can't talk to what your mother is facing because my cancer was different, however Christine is a pro. She's a 3 time survivor and had been through what is facing your mom. Drs. Have to give to a worse case scenario but they don't know for sure that cancer will return, no one does. It's a numbers game. I would suggest doing what you can to stop it n its tracks. If your dr says its a 20% success rate for this surgery I would say get another opinion from someone tops in their field, as you know some surgeons are more successful than others, ideally they will do he surgery then chemo radiation. Best of luck