how do we find distant metastases from breast cancer

[63Fever]

My wife is now NED. When we talked with her oncologist, they told us her chance of re-occurrence 8%. I asked the oncologist how we were going to scan or check her for a distant metastasis. We were told they would go off of symptoms only for distant metastasis, and mammogram only for breast re-occurrence. We saw her radiation oncologist, and she recommended breast MRI for her. The problem is we have Kaiser, and they sub out their radiation services through John Muir. What is one to do, and what are your experiences with this. Just wanting to know if I'm off base here.