Vijayakrishna Gadi, MD, PhD: Hi, my name is V.K. Gadi. I’m the director of medical oncology in the division of hematology-oncology in the department of medicine at the University of Illinois College of Medicine in Chicago, Illinois. Welcome to this OncLive® Peer Exchange® program titled “Changing Treatment Paradigm for HER2+ Metastatic Breast Cancer.” Joining me are my colleagues Dr Chuck Geyer from Houston Methodist Cancer Center in Houston, Texas, Dr Nancy Lin from Dana-Farber Cancer Institute in Boston, Massachusetts, and Dr Michelle Melisko from the University of California, San Francisco UCSF. Panelists, say a few words about yourselves. I’ll start with Dr Geyer. Chuck, go for it.

Charles Geyer, MD, FACP: I’m a breast medical oncologist at the Mary and Ron Neal Cancer Center at Houston Methodist Hospital. I serve as breast committee chair for the NSABP [National Surgical Adjuvant Breast and Bowel Project] Foundation and also the medical oncology cochair for NRG Oncology. I’m happy to be participating.

Vijayakrishna Gadi, MD, PhD: Thank you very much. Nancy, you’re up.

Nancy Lin, MD: Hi, I’m Nancy Lin. I’m a medical oncologist at Dana-Farber Cancer Institute. I lead our metastatic breast cancer program, and I’m the associate chief of our breast oncology division.

Vijayakrishna Gadi, MD, PhD: Last but not least, Michelle.

Michelle Melisko, MD: I’m Michelle Melisko. I’m a breast-focused medical oncologist at UCSF. My research interests are in metastatic disease, primarily CNS [central nervous system] disease, and then also quality of life, patient-reported outcomes, and survivorship issues.

Vijayakrishna Gadi, MD, PhD: Thank you very much. As the title suggests, we’re going to overview the landscape that’s changing and evolving for HER2 [human epidermal growth factor receptor 2]–positive MBC [metastatic breast cancer]. We’ll look at the latest research, focused on the San Antonio Breast Cancer Symposium that just concluded, and how these trials are changing how we manage women and men with breast cancer. With that, let’s get going with the first topic. This is to level-set where we all are in our own practices and the current state of MBC with HER2+ disease in your practices. I‘ll call on you sequentially. What are you seeing in terms of the incidence of each type of breast cancer? Is it changing in your practices? Michelle, I‘ll start with you.

Michelle Melisko, MD: Because I’m at an academic center, we tend to see a population of younger women presenting with more aggressive disease. We end up seeing more triple-negative breast cancers, perhaps more HER2+ breast cancers, and less of the run-of-the-mill older ER [estrogen receptor]–positive HER2-negative breast cancers. We also tend to see more of the rare, unusual subtypes like metaplastic or things like that. But it’s definitely enriched for younger and more aggressive disease.

Vijayakrishna Gadi, MD, PhD: Before I leave you, Michelle, can you highlight 1 or 2 emerging challenges you’ve identified in your recent population?

Michelle Melisko, MD: Of course, we’re very interested in pursuing clinical trial research. With all the optimistic and fantastic breakthroughs, the approval of pembrolizumab in triple-negative disease, and the approval of Enhertu in HER2+ metastatic disease, we have a lot of good treatments. Not necessarily the best treatments. But 1 of the challenges we face is trying to convince women that it’s worthwhile to participate in clinical trials, that there’s still work to be done because there are a lot of unknowns with trial participation, particularly in the face of COVID-19 and the extra work that’s involved. In terms of other challenges in managing patients, CNS disease still remains a tremendous challenge, particularly in the triple-negative and ER+ populations. We have some breakthroughs in the HER2+ space, but we need work in the other areas as well.

Vijayakrishna Gadi, MD, PhD: Thank you. Chuck, from your perspective, what’s your practice looking like? What are a couple of challenges you’ve noticed?

Charles Geyer, MD, FACP: We’re a very broad health care system, so we have more of a mix. We have a large primary care group that feeds into the cancer center, so we see some older patients with mammographically detected ER+. We seem to have few older patients, 80 or 90 years old. We do because we do the clinical trials. Jenny Chang’s interest in triple-negative breast cancer. We get that element of that younger, more aggressive subtype coming to our practice as well.

In terms of the challenges, this is something we’re facing. We have a large hospital and cancer center downtown, but we have a community network with regional hospitals. We’re interested in extending our clinical research efforts out, making that available as everybody is. But there’s always the challenge of the increasing productivity, RBE [relative biological effectiveness] pressures balanced with the time it takes to consent the patient and then monitor and document everything. There’s extra work to clinical research that takes time. That’s a big challenge that we’re all going to be seeing more as payments are “adjusted” moving forward to maintain the ability to do this, because it’s phenomenal what we have before us in terms of opportunity.

Vijayakrishna Gadi, MD, PhD: Nancy, if we can hear from you about the same issues with same questions. What is your practice looking like?

Nancy Lin, MD: In our early stage breast cancer population, I haven’t seen a tremendous shift 1 way or the other in terms of subtype distribution or age distribution over last multiple years. Where we have seen a shift is in people with metastatic breast cancer, and we’re certainly seeing the effects of better adjuvant therapy for HER2+ disease. We see fewer patients with HER2+ metastatic breast cancer than we did 10 or 20 years ago, and that makes it challenging in a way that wasn’t the case before. It’s a good thing to accrue to HER2+ metastatic breast cancer trials. We also have a large group of patients who are living many years with ER+ or HER2+ metastatic breast cancer and reaching for nth-line therapy more often in a way that we didn’t before. In terms of challenges, triple-negative breast cancer remains a major challenge, particularly in the metastatic setting. Even with the improvements with pembrolizumab and sacituzumab, patients still don’t do as well as patients who have other subtypes of metastatic disease. In ER+ disease we struggle with what to do in endocrine-refractory patients because after 1 or 2 lines of chemotherapy, patients tend not to respond to nth-line therapy in the ER+ metastatic space. As Michelle alluded to, CNS disease remains a major problem across all 3 subtypes of breast cancer. Although in HER2, we have options that we don’t in some other subtypes. It’s also very frequent in HER2+ disease. We have patients who’ve exhausted our systemic therapy options for CNS metastasis, and there’s still a clinical need to develop better treatments in that space.

Transcript edited for clarity.