Both HER2 positive and negative in same breast

cholly64

Hello all, This is my first post and I'm not sure where to put it so I apologize if this is the wrong area. I found a lump Aug. 2019 and biopsy came back HER2 negative a MRI was ordered to look for more masses and sure enough 2 more masses were found one small that wasn't biopsied and one a bit larger that was biopsied. My doctor was reassuring that it would also come back negative but to her surprise and the surprise of my oncologist as well it came back HER2 postitve which change my course of treatment from Adjuvant to Neoadjuvant chemo (six cycles of TCH+P) I opted for a bilateral mastectomy with reconstruction. After surgery there was some residual cancer which changed my treatment again from continuing with Herceptin and Perjeta to Kadcyla (14 cycles) and radiation for 5 weeks, which is where my treatment is now. The most upsetting is I have tissue expanders which I was supposed to have only a couple of months before my final implant surgery but now it will be 5-6 months after my last radiation. So uncomfortable/painful and I'm worried that radiation will mess up my skin so much that it will put off implant surgery even longer if ever. Your input is appreciated. But my question is: has anyone ever heard of this happening? Both HER2 positive and negative biopsy results in the same breast at the same time. All my Doctors keep saying how "unique" my cancer is and it really is disconcerting.

Moderators

Hi Cholly, and welcome to Breastcancer.org,

We're sorry for all you're going through and the reasons that bring you here, but we're really glad you've found us. You're sure to find our incredible Community an awesome place for answers, information, and support -- we're all here for you!

While you wait for the ever-helpful responses from our wonderful members, you may be interested in checking out this page from the main Breastcancer.org site on HER2 Status -- particularly, the sections on HER2 Testing and HER2 Testing Accuracy, which states "tissue from one area of a breast cancer can test HER2-positive and tissue from a different area of the cancer can test HER2-negative." In addtion, there's some information on testing results that could be inaccurate.

You're not alone! We're sure others who have tested both HER2 negative and HER2 positive will be by shortly to weigh in.

We hope this helps. Please keep us posted on your treatment and how you're doing!

--The Mods

Redkitty815

I have a somewhat different story, but just had my treatment switched because I was hormone-positive, Her2- according to initial biopsy and triple positive in surgical pathology after neoadjuvant chemo (AC-T) and a bilateral mastectomy. My doctor told me that, while it is unusual, it does happen because cancer is heterogenous and the biopsy may not represent the whole tumor. I think the good news is that, at least at the hospital I am at, being unusual gets lots of eyes and brains on your case. So after their discussion, I have another 12 week course of a gentler chemo and a year of Herceptin ahead with radiation happening after I recover from chemo. I went direct to implant so I don’t have the same challenge of extended time in tissue expanders.

Like you, I have a longer than expected path and a lot of frustration and fear that goes with it (e.g., did missing the Her2 contribute to the amount of residual cancer and worsen my outlook? Can I handle another dose of chemo and extending my treatment by almost a year when all I want is to be done?) I am trying instead to focus on the positives: I get another chance at systemic treatment with Herceptin and there are options like Kadcyla available to get us better outcomes that weren’t there even a few years ago. I am hoping that lengthening this crappy chapter of my life also gives me a much longer story.