any tumor tests to predict which chemos work better?

[sarah]

Hello,
A member of our cancer support group is looking for a way to find which chemos will work for her, she feels she's running out of time and options, has mets to liver and bones, it's a genetic bc. She's looking at a company called Caris Life Science who purports to be able to do that for 5000 euro so I'm just wondering if any of you know of any tests that rule out certain chemos or suggest that others might be more beneficial???? any thoughts? very worried about this person. thanks
Does the oncotype test help? or just for ER status?
health and happiness
sarah