How to watch for brain mets?

[StephN]

Just think that in my case, I was off all chemos and only on Herceptin for almost 2 years when my brain mets got active. I had 2 clean scans the previous 2 years during and after my mets. Those cells could have been just dormant for up to 3 years or more in my brain before getting active and partying hearty!
They could have gotten there even before/during my adjuvent treatment (which was considered aggressive)! Who knows?? I was node positive and high grade, but even with node negative, there CAN be micromets that get out and are not caught. They are SO tiny (remember - 1 million cells on the head of a pin) that there is no way to tell how "clean" we are.
The serum tests are good and I hope they will be approved soon for those without mets.
We need a way for tracking our cancer at a more molecular level then waiting for a tumor of 1/8 inch plus to show on a PET or other scans. And HER2 is something they are finding easy to see in our blood.

Otherwise we have to go with what we now have to achieve the peace of mind we need to get our lives back. My 2 cents worth!