HER2-positive Breast Cancer: What You Should Know

Adam Walker (00:00):
This program has been made possible through the support of an independent grant from Daiichi Sankyo, Inc.

Adam Walker (00:09):
From Susan G Komen. This is real pink, a podcast exploring real stories, struggles, and triumphs related to breast cancer. We’re taking the conversation from the doctor’s office to your living room.

Dr. Ian Krop (00:22):
Breast cancer is not just one disease. There are many different types of breast cancer. HER2-Positive breast cancer is one of the more common types making up about 10 to 20% of newly diagnosed breast cancers. Today, we are talking to Dr. Ian Krop associate chief of the division of breast oncology at Dana Farber Cancer Institute and associate professor of medicine at Harvard Medical School. Dr. Krop is a physician-scientist that treats patients and conducts clinical trial research in breast cancer. He is a leading expert on HER2-positive breast cancer and a Komen scholar. Dr. Krop welcome to the show.

Dr. Ian Krop (01:00):
Hi Adam. It’s a pleasure to be here. Thanks for having me

Adam Walker (01:03):
Well, I’m, I’m excited to talk to you. I have, I’ve talked to many people that have referenced HER2-positive breast cancer and, I think learning more about it’s really important, but before we get into all of that, can you tell us how you got started in this field and how you got to focusing on breast cancer?

Dr. Ian Krop (01:22):
Yeah, so I guess I was finishing training about a little more than 20 years ago and right about then was when people and oncology were starting to realize that breast cancer was not just one disease, but multiple different kinds of diseases, as you mentioned. Along with that there started to be development of new drugs targeting each specific kind of breast cancer. And so I thought that people like me who had laboratory training as well as clinical training in oncology could be useful in trying to understand how best to use these new targeted therapies and, and potentially develop new therapies. So that’s kind of what got me interested in breast cancer and that’s basically what I do these days.

Adam Walker (02:12):
Oh, that’s fantastic. You had a vision and you pursued it. I love that. I love that. So I know your focus, you focus your research on HER2-positive breast cancer. As I mentioned, we talked about that on this show many times. Can you just tell us more about that? What is that?

Dr. Ian Krop (02:27):
Yeah, so, so what’s unique about these, HER2-positive breast cancers is that at some point in, as they’re developing, they have a mutation in their DNA that leads to way too much of a protein called her to on the surface of these cells. And so what is HER2? So HER2 is a protein that’s, all cells have some and what its function is, is to basically tell the cell to grow more aggressively and, and to be resistant to dying under conditions of stress. And what happens is when you have millions of these, HER2 proteins on each cancer cell, which occurs because of this mutation all of these proteins are telling the cell to grow more aggressively and resist dying. And so that’s what happens is it, you lead to a cancer that tends to be more aggressive than other kinds of cancer and, and you know, be resistant to some types of therapy.

Adam Walker (03:28):
And so that’s, what’s unique about these, HER2-positive breast cancers is that they, they have all these, HER2 proteins and it leads to cells being kind of having some bad behavior, but it was this realization that the reason why these cancers were behaving so badly was because of this, HER2 protein that led to development of drugs that block that HER2 protein. And since that development of these new drugs that, that target her to now these cancers actually are very well treated with these new therapies and patients do incredibly well. Now that we have these new therapies,

Adam Walker (04:05):
Oh, I love that. I love it. So then, so let’s talk about patients for a minute. If someone is diagnosed with this type of breast cancer, what should they know and what can they do?

Dr. Ian Krop (04:15):
Right. So again, the first thing to remember is that in general now, because of these new targeted therapies, people with HER2-positive breast cancer tend to do extremely well. So, you know, that’s the first thing you should take into your discussion with your doctor is that, you know, people in this kind of breast cancer now do very well. What it means from a practical standpoint is that people need to get some type of her to therapy. And, and as we may talk about later, there’s a number of these new, our two therapies. And in general, these work better with chemotherapy rather than just by themselves. So for most people with HER2-positive breast cancer, they get some combination of a, HER2 therapy meaning a drug that specifically blocks that HER2 protein plus some type of chemotherapy. And with that combination we see very high cure rates with this kind of breast cancer when patients are diagnosed for the first time.

Adam Walker (05:19):
Wow, that’s fantastic. And, and I know you mentioned you’ve been in this field for about 20 years. So this question may go back a little before your time, but we we’ve come a long way in treatment in this field. If someone was diagnosed 25 years ago versus diagnosed with HER2 breast cancer today, what is the difference in the progress?

Dr. Ian Krop (05:37):
Yeah. And so that’s where, you know, this, you know, understanding of why these cancers behave the way they do. And the development of these new drugs really has made such a dramatic difference. I mean, this is one of the real success stories in, in oncology. So, you know, back about the time I was starting treatment I mean, starting you know training again, as I mentioned, people tended to do pretty badly with these kinds of cancers because they were so aggressive and a lot of patients had recurrences of these cancers even when they got drugs like chemotherapy. But with these new, HER2 targeted drugs mixed in with the chemotherapy now it’s actually better to be diagnosed with HER2-positive breast cancer. People tend to do better with this kind of breast cancer than most other kinds of cancer. And so the vast majority of patients are cured with this kind of cancer compared to, you know, 25 years ago when a lot of patients were having recurrences at this kind of breast cancer. So it’s really night and day.

Adam Walker (06:39):
I mean, it’s really encouraging to know that the science has come that far that quickly. So thanks. Thank you for sharing that. So I want to shift just a little bit up and talk about MBC patients. So what should MBC patients know about the, HER2 type of breast cancer?

Dr. Ian Krop (06:55):
Yeah, so just so everybody’s on the same page. So MBC, you know, we use stands for metastatic breast cancer and, you know, metastatic is just a word we use to describe cancers that have spread beyond the breast and the lymph nodes around the breasts. So it just means cancer that’s gone somewhere else in the body. And what typically means for patients who have metastatic disease is that they need to be on some type of treatment essentially indefinitely. So it means basically some type of long-term treatment. And you know, the problem with that is that over time, oftentimes cancers can learn to be resistant to a specific treatment. They learn how to get around that treatment. And that happens in HER2-positive breast cancer as well. But what’s really, you know, kind of unique about HER2-positive disease. Is that not only do we have, you know, one or two drugs that block her too, we now have eight or nine.

Dr. Ian Krop (07:54):
And in fact, we have four different new HER2 blocking drugs, or HER2 targeting drugs that have just been approved by the FDA within the last year. So this is a field that’s really moving very quickly and it all stems to this idea that if you can figure out what’s driving a cancer in this case for two, it’s easier to develop new drugs to attack that weakness of the cancer. And so that’s really, what’s kind of been the hallmark of, of, of treatment of HER2-positive disease has been the realization that the problem here is this HER2 protein. And, and we’ve now developed a number of new drugs that target that HER2 protein. And when they, all of these drugs are pretty effective. And so for patients who have this kind of disease, when it’s metastatic, they do need to change typically from one drug to another over time, but we have a lot of these new drugs. So hopefully we will have always have a drug available for someone, even if it’s become resistant to one drug, we can switch to another drug. And, you know, the goal is that we can keep developing drugs faster than the cancers can learn how to become resistant.

Adam Walker (09:02):
Yeah. Yeah. That’s great. That’s great. I appreciate you taking the time to explain that and, and even walking through what NBC is to, to bring us all along. So all right. So what are some questions that individuals with HER2-positive breast cancer should be asking?

Dr. Ian Krop (09:16):
Yeah, so, I mean, I think, you know, it’s important that everybody understands what the, HER2-positive breast cancer is in terms of, you know, why we call it that and, and what you know, what drugs are available for them. You know, you know, people are in many different situations. Some people have newly diagnosed for two positive breast cancer. That’s just confined to the breast. Others have cancer cells that are in the lymph nodes and others have metastatic disease that spread to other places and, and the treatment for those different situations is quite different. In general, it all involves some combination of a, HER2 therapy and and in many cases, chemotherapy but it’s, you know, the specific, you know, regimen that we use depends on a person’s specific situation. So I think in terms of what you need to know from your doctor, it’s, you know, what stage, you know, where exactly is my breast cancer and what are the goals of the treatment and what are my, what drugs are going to make the most sense for me at this particular point in time. But it’s, it’s, you know, it’s certainly not a one size fits all situation. That’s not true for any kind of breast cancer, but specifically in HER2-positive disease, we have a lot of different drugs and it all depends on exactly what you know what that particular patient situation is.

Adam Walker (10:39):
Of course, of course. Okay. so Dr. Krop, this has been great. I’ve learned a lot. Last question for you, after all your years of medical practice, is there any advice that you can share with our patient community?

Dr. Ian Krop (10:53):
Yeah, so, I mean, I think that’s a great question and, you know, my general sense or my general recommendation for people who are meeting their oncologist for the first time, or even if they’ve already met, you know, even if they’re going back for multiple visits, it’s just to ask questions. You know, I think it’s really natural for all of us, for our brains to come up with worst case scenarios. When, you don’t know, you know, the answer to a question, so we’re always worried about something you know, that could go wrong. And I think asking your oncologist, you know, questions that are bothering you that are troubling, you can be really helpful, especially in this kind of breast cancer where we have so many good options and people tend to do so well. I think if you just, you know, try to get, you know, a real hand handle on what the landscape is and what, what, what people are recommending, you know, for you right this minute, then what to expect, you know, six months from now, I think understanding that and having a roadmap, you know, for what to expect can really go a long way in terms of helping, you know, you people get through what, what we’re asking them to do, because, I mean, even though people do very well with this kind of breast cancer, it does typically involve a, you know, a substantial amount of treatment, you know, even for patients with early stage disease.

Dr. Ian Krop (12:19):
We, you know, our therapies usually lasts at least a year. So it’s not something that you’re just going to go in and get your treatment and be done. It’s going to go on for a while. So kind of getting a handle on all of that is really helpful, but again, I just want to just reiterate that patients, people with this kind of breast cancer now tend to do very well. But you know, I think knowing the facts in your particular case, it can be really helpful.

Adam Walker (12:45):
Yeah. Now, doc, Dr. Krop, this has been great. Thank you for taking the time to explain this thoroughly. I’ve never understood it like I do right now. So, thank you so much for your time today. Thank you for joining us on the show.

Dr. Ian Krop (12:58):
Sure. My pleasure.

Adam Walker (13:05):
Thanks for listening to Real Pink, a weekly podcast by Susan G Komen for more episodes, visit realpink.komen.org for more on breast cancer. Visit komen.org. Make sure to check out at Susan G Komen on social media. I’m your host, Adam, you can find me on Twitter @AJWalker or on my blog AdamJwalker.com. This program has been made possible through the support of an independent grant from Daiichi Sankyo, Inc.