The Herceptin will not change the over-expression capabilities of the cancer. It will however prevent cells from multiplying. If you have a tumor and take Herceptin, you will likely have tumor shrinkage. If you however stopped taking the Herceptin then that tumor will begin to grow again.
Remeber that Herceptin was primarily created for the metastatic HER2+ bc patient.
Navigate through the below website- it will tell you how herceptin works- for the metastatic patient.
Not enough data has been collected to gauge how beneficial it has been for the Stage I, and II bc women. Evident from the posts on this board, it is clear that Herceptin shrinks tumors and helps the immune system fight-off cancer. And it absolutely helps when used with taxol. It also prolonged the life of many Stage IV patients too. Some women still progress (very few) with it and others (mostly) are NED or stable. Some women on this board have been taking Herceptin for 6+ years! I think that once the Stage I, II and some III's are off the Herceptin, only time will tell exactly what it did for them. We can only hope that the success brought forth by those women with more advanced disease that are taking Herceptin will be the promise that it will work for those of us with earlier stage. I mean, if it shrinks mets, and Stage I's supposedly do not have mets, then our immune system fortified by the herceptin should kill off any errant cancer cells. Because it is relatively safe to take, I suppose we are lucky it will be there if the earlier stages reccur...
Maria (MTS)
http://www.herceptin.com/herceptin/p...about/work.jsp