ER-/PR+HER2- IS THIS POSSIBLE

Barbara, it is possible for a tumor to be ER- PR+ (and HER2-) but the combination of ER- and PR+ is uncommon.  I've even read that some oncologists consider it a lab error.

Here's a discussion about the problems of false-negative results with either the ER or the PR part of the hormone receptor tests:  http://www.medscape.com/viewarticle/589766

Although there are skeptics, many oncologists do recognize the ER- PR+ phenotype as real (not a lab artifact).  It accounts for around 8% of BC tumors here in the U.S., according to the studies I've seen  Here's a short article written for the general public:  http://foodforbreastcancer.com/articles/er--slash-pr%2b-breast-cancer

Here's an abstract from the 2007 ASCO meeting that discusses the variations of ER, PR, and HER2 subtypes (including ER- PR+ HER2-) among BC cases diagnosed in California:  http://www.asco.org/ascov2/Meetings/Abstracts?&vmview=abst_detail_view&confID=52&abstractID=40116

That's just a quick survey of some of the info.  So, yes, it's possible, although I don't know anyone with that dx.

otter

 I posted somewhere else that my pathology report said 60% + but onco test was neg for PR.

I also did alot of ? but if ER+ they do tamoxifen. I am learning now that tamoxifen may not work if PR -.

We need more research in that area.. I go back in Dec and I will ? this again.