Should Borderline Her2+'s use herceptin??

[Cathya]

Hi;

I am waiting this week for news that I can go back on herceptin. My onc ran an echo last week and said that if it was normal I would be continuing herceptin. I had heart issues which took me off it for the last 4 months but I have had it for 8 previously. Now, thinking of being borderline her2+ (by Fish) and ER+/PR+ I am wondering if it works for folks like me? I also am on Arimidex for the ER/PR+ part. I took AC and Taxol and radiation on the left side. I want to take it, don't qualify for the lapatinib (which I would love to take along with the herceptin) but just wonder. Anyone out there with info on this? Thanks

Cathy

[mcgle]

It is my understanding that herceptin may be of limited use for us HER2 borderlines. I think they take all other prognostic indicators into account when making the decision, but am not sure about ER/PR receptivity.

Best to quiz your onc about this.

Sorry I couldn't help more.

Mcgle

[Cathya]

Mcgle;

I appreciate your response. I kind of wonder if there is enough experience with herceptin for my onc (or most for that matter as I think very highly of my onc) to be well informed. I wonder if there is any new research out on us borderliner her2+'s.

Cathy

[Becky]

There is an early release article for the next issue of the Journal on Oncology (ASCO) dealing with this issue (which I cannot cut and paste). In a nutshell, it had always been accepted that borderline Her 2 (2+) and FISH borderline would not benefit from Herceptin. However, there is question on this thought based on additional genetic markers.


It is well understood that Her 2 does not work in a vaccum. It loves to cross talk and other receptors love to talk to it. This article states that about 35% of Her2+ pathology is also strongly Her1+ and that 97% of all Her2s have some evidence (no matter how mild) of being Her1+. Her1 and Her2 need to be positive for Her3 to be active and if active, Her3 can phosphorylate on its own without dimerization. Therefore, they suggest, if Her2 is only mildly overexpressed but Her 1 is expressed, Herceptin could slow down or stop tumor growth due to inhibiting the Her1/Her2 crosstalk that activates Her3 (if expressed even mildly).

Hopefully you understood this. Other pathways are also discussed in the article and how they are influenced by her3 (p13K etc).

So... in some women, even if mildly overexpressed, Herceptin can help.

I will see if I can paste the article.

Kind regards

Becky

[Bev]

I thought that ER+PR+ seldom have HER 1+, which on the face of it might mean it has limited value for ER/PR +, borderline HER2+. I may be wrong about this as all the studies get jumbled in my mind. I myself, would take it as long as I could.

[Becky]

You are very right Bev. I was kind of answering the question in that in some cases, borderline could work out well. If ER+, it might not make a difference if the ER is suppressed.


Becky

[Bev]

Thanks Becky, I think so much info will become available in the next few years that will change the facts as we know them now. In the meantime we just have to go with the facts with where they are now. It is so complicated. I'm looking forward to a time when it becomes so clear and easy to deal with like polio. I have my optimist hat on today.

[Kimberly Lewis]

I was positive by IHC and weakly positive by FISH (40%). At Duke that meant no Herceptin for me. When I changed Onc's (wait at Duke was 2hours in office min.!) The Onc from Duke wrote my new Onc saying that Herceptin would be beneficial for me! Wow, I have been on Herceptin ever since. I guess there is no other safety net right now and there is so MUCH they don't really know. That's my experience for what little it's worth. Stage 3a - 7 nodes positive er+ pr weakly positive...

[Cathya]

Thank you so much for responding. I am looking forward to going on it as I believe in fighting this disease with all guns....assuming they have bullets...lol. Is it possible to get our tumor tested privately somewhere to find out about her1, etc. I guess my original tumor is in parafin and likely the biopsy from the second one so would it work anyway?? I am glad to be taking Arimidex for the hormones but wonder about lapatinib ..... later when it's available. I also worry that my heart troubles will start up again although it niggles around in my mind that I have heard sometimes they don't recurr.

Cathy