Recurrence in Her2 patients...

Some of you may have seen my post recently about what drug to take post-treatment for Her2 positive but ER/PR negative. I am almost thinking that I want to take Herceptin for a year after my radiation, but I have a lot more to read andthen to discuss with my oncologist.

I have another question....I am in need of some research advice. I need some data that discusses Her2 recurrance and type of cancer cell presented at recurrance. In other words, when Her2 positive patients have a recurrence, how often is the new cancer Her2+ and how often is it negative for Her2? And does it matter whether or not the patient is or has become post-menopausal after treatment--does that affect whether or not the recurrence overexpresses Her2? Has there been enough data collection of Her2 info to have statistics on this?

thanks!
Val Pfeiffer

Val,

From reading that I have done, HER2 positive rarely if never reverts to HER2 negative, even for recurrences.

On the other hand occasionally HER2 negative cancers will sometimes turn HER2 positive when they reoccur.

I found this:

Can HER2 Status Change?
by Bonnie Bassett-Spiers

©2004 Willow Breast Cancer Support & Resource Services

The answer to this question is, possibly. A very early research study published in the Proceedings of the National Academy of Sciences (PNAS) in June 2004 looked at 24 women whose primary tumours had been HER-2 negative and then later developed a recurrence. The study was investigating a new method of testing HER2 by looking at circulating tumour cells in their bloodstreams. What was somewhat surprising to the researchers was that 9 of the 24 women who had previously tested negative for HER2 were now HER2 positive using this new test.

Obviously, this research is very preliminary and that much more work needs to be done before these findings have any bearing on treatment decisions. However, a closer look at women who test HER2 negative but have cancers that behave more like HER2 positive may be warranted.

(Article: "Her2 status reverses itself" by Caitlin Cox, MAMM Magazine, Sept/Oct 2004.)




Warmest Regards
Joe

Thank you Joe. I also wonder how often a previously her2+ patient has a whole new cancer recur....non Her2 unrelated to the first cancer.

That's my problem. My second opinion doctor told me he wanted to do a biopsy to see what kind of cancer I have now. But the spot is between my lungs and I'm afraid to do that. He said that if it's not the breast cancer her2 +(as it was 5 years ago) then the herceptin and xeloda won't work. Since I opted not to get the biopsy, I won't know if it's working until my next petscan in two months.The second doc said it could now be lung cancer or lymphoma, in which case I would need a completely different drug.So, I am waiting and praying that the drugs are working. Goc Bless, Cathy