ER/PR + %

Karina121293

Hi everyone. Strange enough, but never paid attention to the percentage of ER and PR. Just know I am positive and that's all. Would like to know more now.

Please help me understand the percentage in ER+/ PR+. I am at 50%. Is lower better than higher or vice versa?? Many thanks in advance.

Karina 

cp418

see this link.  Your percentage is high which means you are considered hormone positive with more treatment options.  Sending Hugs to you.

http://www.breastcancer.org/symptoms/diagnosis/hormone_status/

Gitane

Hi Karina,  I came across this information a while back.  It is from the College of American Pathologist's newsletter,  "CAP Today", April 2010.

 

On one point, everyone agrees: Current ER/PgR testing, regardless of how accurate it is, doesn’t tell the whole story. “For all practical purposes,” says Dr. Osborne, “having a correct positive ER or PgR result doesn’t guarantee that the hormonal therapy will work.”

And, says University of Michigan oncologist Daniel Hayes, MD, another co-author of the guideline, the benefit seen from hormonal therapy seems to level off at about 30 percent to 50 percent positivity. “A patient is not more likely to benefit if her tumor has 100 percent positive cells versus 50 versus 30.”

faithfulheart

Gitane, that sucks!!  I'm 98% ER pos, why bother on the hormonal theropy!!  Did I read that right?

Gitane

I think they are saying that not everybody who is ER+ benefits from endocrine therapy.  We all know that.  Some of us don't benefit, others benefit for a while then stop, and still others benefit greatly.  They don't know who fits into which category.  I think they are saying this...  If our BC is destined to respond to the therapy, higher levels (above 30% I guess) don't mean we benefit more or are more likely to benefit.  Now I am interpreting it that way.  Maybe I'm wrong.

mmm5

what if you are very low like 16 percent?

Gitane

Hi mmm5,  I went back to that same article and found that if only 1% of cells show moderate staining, there is benefit to endocrine therapy.  Here is what they said:

The evidence in support of the one percent cutoff comes from research by Washington University pathologist D. Craig Allred, MD, one of the guideline’s co-authors and a member of its steering committee, and colleagues (Harvey JM, et al. J Clin Oncol. 1999.17:1474–1481). Guideline co-author David Hicks, MD, says the researchers took tumors tested by IHC’s predecessor—ligand-binding assays—and performed ER testing on them using IHC. “They found that if the Allred score... was below three, the benefit from endocrine therapy appeared to be lost.” A score of three equates to either one to 10 percent of cells showing weak staining or as few as one percent of invasive tumor cells showing moderate staining, says Dr. Hicks, professor of pathology and laboratory medicine at the University of Rochester (NY) Medical Center. This has been simplified to greater than one percent tumor cells staining for ER as an indication that the patient is a candidate for endocrine therapy. 

weety

Thanks, gitane, for posting that.  That's kind of what my onc told me (I think I'm about 10%ER) but I was hoping they would decide I wasn't getting much benefit so I could stop it.  Bummer. . . Sigh. . . She said that you just never know which part of a tumor cell will get turned on and "we want to cover all our bases."

Karina121293

Thanks everyone for the discussion.I was hopping that after hysterectomy, I could avoid hormonal therapy. but no chance per my onco. From the other hand regardless the SE, it's good to be on the safe side.

Karina

AnacortesGirl

Karina -

That was one of the things I learned, also.  I had the mistaken idea that the estrogen just came from the ovaries and uterus.  But it appears our bodies have "contingency plans" for other ways to generate the estrogen.  Shoot! 

But I guess we have to look at the positive and at least we have the hormonal therapy in our arsenal of weapons.

Karina121293

AnacortesGirl, exactly. After a year of full on active treatment, it's safe to know we have something else to guard us afterwards. Just hope for the least SE, yet to decide which hormonal I will be taking.

bak94

So does that mean that if I am 3% er positive I should get tomaxifen? My mo did mention it, but wanted to confirm the biopsy results with the pathology after I have bmx, which is after chemo for me. I will be having a full hysterectomy because I am brca1 positive.

weety

I'm not sure. . . but my onc did say that you are either estrogen postive or not--just like you are either pregnant or you're not.  She told me any estrogen involvement warrants anti-hormonal treatment.  I'm at about 10% and on femara.