Assisting Community-Based Oncologists and Surgeons in Making Neoadjuvant Treatment Decisions for Patients with Early Breast CancerNeoadjuvant treatment of HER2-positive tumors
2:31 minutes.
TRANSCRIPTION:
DR MAMOUNAS: Traditionally, the HER2-positive patients had a pathologic response with chemotherapy in about 20% to 25%. And then when trastuzumab was incorporated in neoadjuvant regimens, it jumped to about 40% to 45%. So that was a huge jump when you think about it. It’s almost like doubling of pathologic complete response. And eventually, when pertuzumab was incorporated into the regimen based on the FDA accelerated approval of pertuzumab, pathologic response rates went up to about 60% overall. And then if you look at it within the ER subtypes, always, pathologic complete response is lower for the ER-positive, HER2-positive — about 50% or so. And for the ER-negative, HER2-positive, it jumped to almost past 70%. So that’s the numbers I can quote to patients now, 50% with dual anti-HER therapy for the ER-positive, HER2-positive and about 70% for the ER-positive — ER-negative, HER2-positive. DR LOVE: But in spite of these pathologic responses in the neoadjuvant responses, Kim, the basic paradigm, does it still stay the same? In other words, that you get the same benefit in terms of disease-free and overall survival long term, whether you give it preop or postop? DR BLACKWELL: That’s been a little bit difficult to – to prove, because we don’t have a randomized study of trastuzumab in the neoadjuvant setting only or started in the neoadjuvant setting and then continued postsurgery versus doing the surgery — we don’t have the B-18 equivalent of a HER2-positive study. It would be an interesting study to do. My hypothesis would be that, because trastuzumab is so effective in the treatment of HER2-positive breast cancer, it’s almost impossible for me to imagine it would be detrimental to incorporate it in the neoadjuvant versus the adjuvant. And I personally think moving highly effective agents up earlier in the treatment course should benefit patients. I don’t think there’s any reason to believe that it would harm patients. And so one of the big advantages of incorporating trastuzumab in the neoadjuvant setting is you’re getting a highly effective agent started immediately to fight systemic micrometastatic disease as opposed to even a 6-, 8-, 9-, 12-week, depending on what kind of surgery and delays and all of the various other things that you would get by giving it in the postsurgical setting. So I think there is a real potential advantage. It’s just not been a proven advantage. |