Joan--
My oncologist recommended the test that Guardant does. (
http://guardanthealth.com/). It tests circulating tumor cells and identifies mutations and amplifications.
My test showed three mutations and three amplifications. One of my amplifications is HER-2 (of course!). One of the mutations is P-53. There are drugs in phase 1 clinical trials for several of the abnormalities I have. My oncologist said a successful P-53 drug would be a "home run." She's working on one in her lab. Here's more about that mutation:
https://ghr.nlm.nih.gov/gene/TP53
I think my insurance covered the test. At any rate no one has billed me for it.
Amy