IDC that is Her2- and Her2+ ?!?!

smlowry7

Hello!

I am wondering if anyone else has experienced what I am as far as the pathology of their CA goes. I was dx in Feb 2016 and due to the size of my tumor the radiologist wanted a biopsy from both sides of my tumor. The results were tumor 1) 100% ER+, 90% PR+, Her2+++ 2) 100% ER+, 95% PR+, Her2-. The comment on the path report said that most of tumor 1 was completely her2-, but 10% of the tumor cells show strong membrane reactivity and so the result is regarded as positive.

I saw my MO's partner today because she was out of town for an emergency. She mentioned that she thought my tumor would have melted more by now since I have treatment #4 of 6 of TCHP tomorrow and my tumor is her2+. I explained my "unique" situation and she went over my path report with me. I asked if maybe the HP had taken care of the 10% that was her2+ and now only her2- was left. I also asked if it would change my treatment plan or if I would need another chemo treatment that is her2- specific. She said she would talk to my regular MO about a biopsy now vs waiting until surgery after chemo is done. She also said that her2- would have a different combo, but since i had her2+ as well getting the HP was important. I asked if I could do a her2- specific chemo treatment for extra coverage and she said it wasn't protocol, but my situation was complex because usually it's either her2- or her2+. They sent my specimens for blueprint and it was inconclusive due to not having enough tissue sample and they couldn't find any cancerous cells in the tissue they received. How the heck can you be able to diagnose with a biopsy sample and then the next people can't find any cancerous cells to test at the molecular level for the her2 status?

Has anyone had a similar situation? Thanks in advance!

meg2016

I also have tumors that are heterogeneous on Her2 expression. This was only find after I got a second opinion on my tissue samples. Because of that, I began with THP (4 rounds), and have had some shrinking based on an MRI, but will continue now to AC as well to see how they respond to that. Curious to find out what your MO recommends. It is also my understanding that tumors that are strongly ER/PR+ don't respond as well often to the neoadjuvant TCHP (some response, just not complete response.)