Tumor Profiling and Breast Cancer Treatment

[00:00:00] Adam Walker: This podcast is brought to you by Exact Sciences, with a leading portfolio of products for earlier detection and treatment guidance. Exact Sciences helps people face the most challenging decisions with confidence

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.

Every cell in your body has genes that contain the blueprints, or genetic code, for your body.  Cancer develops when changes – or mutations — in some of these genes cause the cells to grow uncontrollably and take on new characteristics.  Tumor profiling, also called molecular profiling or genomic testing, gives information about the specific changes in the genes of cancer cells.

Today we are joined by Dr. Christy Russell, Vice President of US Medical Affairs at Exact Sciences, who will talk with us about tumor profiling in breast cancer. Welcome to the show, Christy!

Well, I’m excited to talk with you about this. This is something that I’ve, I don’t know anything about at all. And I’d imagine a lot of our listeners probably don’t know much about it. And so, uh, let’s start with the basics. What is tumor? Profiling slash genomic testing. What is that?

[00:01:21] Dr. Christy Russell: So tumor profiling looks at the specific changes within the genes in cancer cells. And so it’s meant to provide information about that cancer, how it might behave, how aggressive it might act. And if there are specific drugs for which, uh, there might be effectiveness. Based on specific gene abnormalities within the cancer cells.

[00:01:49] Adam Walker: Okay. And so I assume then you, the idea being that you get a profile. Of the cancer. You sort of understand how it works and what it responds to, and then you seek the right drugs and the right, uh, treatments to, to combat that,

[00:02:04] Dr. Christy Russell: right? Yes. And this is where the nomenclature of precision medicine or precision oncology has come from to not view patient with she has breast cancer.

So let’s throw everything at her. It’s trying to be more intelligent about. The drugs that may be most effective, um, based on what the cancer is telling us genetically. Okay.

[00:02:31] Adam Walker: That’s fantastic. And so, uh, so I’ve heard of genetic testing, but I’ve not heard of genomic testing. So how are genetic and genomic testing?

[00:02:40] Dr. Christy Russell: Right. They’re both tests on genes, but genetic testing really refers to testing on a person’s normal genes that are in their normal cells. Usually when we talk about someone, especially with breast cancer, that we’re going to test someone who may be at risk for breast cancer to see if it’s something that they may have inherited from either their mother or father.

We will go after normal tissues. So this is normally a blood test or a cheek swab. We’re just getting normal cells that are in the lining of the mouth. And we’re looking for very specific mutations in genes that are known to be linked with a higher risk of getting cancer. And in this case, we’re talking about breast cancer.

So. Understanding your risk of developing a cancer or another disease. There are genetic tests for other diseases as well. That’s genetic testing, and it’s really referring to a hereditary method of transmission of the abnormal gene. Now, if you have. If you have been passed these abnormal genes, um, through a parent, they are in every cell in the body so that you could test any normal cell, um, to understand whether that mutation is within all the cells of your body.

And one of the more common. Groups of mutations that we talk about for breast cancer are the B R C a one or B R C a two genes that stands for breast cancer, one or breast cancer, two genes. But again, these are your normal cells. We want to know whether there’s some kind of mutation in those normal genes in every cell, in your book.

That’s very different from genomic testing. So genomic testing is profiling. The genes in the cancer you’ve already developed a cancer. And so it’s, we would remove cancer cells by biopsy, um, getting tissue or by liquid. Getting cancer cells circulating in the blood. And we would look at specific genes within the cancer and of that those genes.

Tell us how aggressive that cancer might act. Um, are there very specific mutations that again, that can direct us toward a specific therapy being more effective. So genetic testing, hereditary, uh, ways of transmission of abnormal genes, genomic testing. What happens once the cancer is developed? What are those genes just in the cancer cells doing and what are they telling us about the most effective treatment?

[00:05:24] Adam Walker: Hmm. Okay. That’s fascinating. And so, so how D how can tumor profiling inform whether or not someone needs chemotherapy? Like how does all that work?

[00:05:33] Dr. Christy Russell: So for breast cancer, uh, we, uh, at exact sciences have a product called the Oncotype D occupied DX breast recurrence score test. This is a test where we’re testing 21 genes.

Within the breast cancer cells, 16 of the genes are cancer genes. Five of them are referenced genes. The specimens are sent to our lab and we generate a report that indicates several things. One is, um, whether the cancer, uh, is responsive. To chemotherapy. So let me walk you through that. When we do genomic tests on cancer cells, uh, specifically this Oncotype DX breast recurrence score test is only done on breast cancer cells that are signaling that they need estrogen to grow.

And those are called hormone receptor positive breast cancer cells. We also are only testing in breast cancer cells. Where a gene called her to new, which is a normal gene that, that gene is functioning normally. So our testing is only done on what we call hormone receptor positive, her two new negative, early breast cancer.

So. So we get the specimens of the breast cancer and we test for the 16 cancer genes. Every patient has the same genes tested for this genomic test and the five reference genes, which are the same again for everybody where they get the test. And it gives two pieces of information. One is. Because this cancer is known to be dependent upon estrogen to grow and because whether we are pre-menopausal or post-menopausal, we make estrogen in our body, we know that those cancers will shrink.

Or be eradicated if we can block that estrogen in the body. And these are called estrogen blockers or hormone therapies that are like anti-estrogen therapies. And so for our patients that get this score, we are presuming that they are all taking an estrogen blocker for a minimum of five years. And the data would show that if you take the estrogen blocker for a minimum of five years, you can reduce your risk of developing metastasis or that early breast cancer spreading to other parts of the body.

By some studies will say 40%, but the feeling is that if you took the therapy for all five years, you would reduce your risk of developing metastasis by having. Now that is the presumption. So let’s say I’m diagnosed with breast cancer. It is estrogen receptor positive or hormone receptor positive her two negative.

It doesn’t appear to have spread. The specimen will be sent to our laboratory for testing. And we will presume that this patient will be placed on an estrogen blocker for five years. So our test tells you two pieces of information. One. What is my leftover risk of developing metasticies. If I do take this estrogen blocker for five years, what is my leftover risk?

So if I don’t take the estrogen blocker, my risk is 10% and I do take it. It’s 5% are our score or our tests. We’ll be able to give you that information. The second piece of information that gives you is. Will my cancer respond to chemotherapy. Will it shrink with chemotherapy? If I take chemotherapy, do I have an increased chance that this cancer will never metastasize or show up anywhere else in the body?

Now, when we say, what is my leftover risk? If I take an estrogen blocker. That’s called prognosis. And that is what your underlying risk is based on the score and the features of your cancer. The chemotherapy portion is prediction. We can predict with this 21 gene recurrence score. Whether you will benefit from chemotherapy or not.

So it is prognostic, what is my underlying risk? And it is predictive. Will I benefit from chemotherapy? And we have multiple studies that have shown consistent results. If you have a lymph node, negative breast cancer, and you think, oh, I’m good. I’m clear, but you have a hygiene score by our test. You actually probably need chemotherapy to significantly improve your chances of this cancer.

Not coming back. Hmm. On the other hand, if you have a low score, it would suggest you would get no benefits from chemotherapy and you shouldn’t be offered chemotherapy. And this is true now for women who are lymph node, negative, or even women with up to three positive lymph nodes for whom the standard of care was to give them all chemotherapy.

[00:10:51] Adam Walker: So you mentioned a minute ago, uh, metastatic breast cancer. Let’s dive into that just for a moment. So how can genomic testing guide therapy selection in metastatic disease?

[00:11:03] Dr. Christy Russell: So our Oncotype breast recurrent score assay is just for women with early breast cancer. But exact sciences has two other assays for women with metastatic or advanced breast cancer.

This is now testing the cancer where it’s spread so that we would again get a piece of tissue from the area of the cancer spread to so. For example for breast cancer, if the cancer cells showed up in the liver or the bone, we would get a specimen from there. And we would test for the specific mutations that are occurring in the cancer cells that have spread.

So we want to know. What is happening with those cells? What genes have been mutated and what abnormal proteins, those new genes that are mutated are, are developing or creating that we can measure. So we have two tests. One is called Oncotype. Map pan cancer tissue tests. And we have a second test, which is called gym extra tests.

One is much deeper in the number of genes that tests. The second is, has less genes that it tests, but it tests for the huge majority of genes for which there are drugs that are available for women with metastatic cancer. This is a growing field where we’re looking again for precision therapy, the right therapy for the cancer at that time.

And the patient’s cancer experience.

[00:12:38] Adam Walker: Wow. So, all right. So we’ve talked about sort of what this testing can offer in terms of guiding treatment and in guiding sort of how we approach that cancer. So when should someone who’s interested in genomic testing have that conversation with their doctor? Is there a certain time that produces better outcomes for patients?

[00:12:59] Dr. Christy Russell: Well, I am an oncologist. Uh, I am no longer practicing, but with my patients, I like to talk from the very beginning. About all the things that could happen related to their cancer. So if you have a patient who presents with early breast cancer, we would talk about what is the right surgery? What is the right?

Do you need radiation or not? Do you need chemotherapy or not? Do you need an estrogen blocker? How long should you take it? And. Begin to introduce it that time, the different kinds of testings that can help guide therapy for that patient’s cancer. And so this conversation I believe, should happen on many different occasions.

One when you’re first diagnosed and then. You have a new decision point that occurs with your cancer? Is there evidence that the cancer has come back? Have I developed a new kind of cancer? I think the question of genomics, what is unique about my cancer? How that would make me. Want to take a specific therapy and how are you making that decision?

And are there genomic tests that can be more precise in helping me decide the best therapy for my cancer? And so I think every milestone along a cancer journey deserves the question. And it’s a conversation between the patient and his or her physician.

[00:14:27] Adam Walker: You know what I mean? I like how you framed that at every decision point, you know, I don’t think I’ve ever really thought of a cancer journey like that, but to your point, there are a lot of different decision points along the way, and it would make sense to consider this kind of testing at each one of those and determine does this, will this help us to have a better outcome with that?

[00:14:46] Dr. Christy Russell: Yeah, and it’s not just chemotherapy or hormone blockers. It’s immunotherapy. It is. Is there a genomic test that can tell me whether I’ll benefit from radiation therapy? And so there are many things that have happened for, uh, decisions for a patient who is an early cancer, who likely is cured of that cancer, but needs the optimal care and optimal testing and optimal therapy.

And for patients with advanced cancers, Know, that’s a very frightening situation and you want to make sure that you’ve optimized your best options for as long a life as you can have. And as normal a life you can have while you’re experiencing that advanced cancer.

[00:15:32] Adam Walker: Yeah. That’s right. So last question.

Where can our listeners go to learn more about genomic testing?

[00:15:41] Dr. Christy Russell: Well, first of all, komen.org has a lot of great resources, including questions to ask your doctor facts for life, then help explain your diagnosis and prognosis, and even an animated video. Blain’s the difference between genetic and genomic testing.

So Coleman itself has a very, very rich portfolio of educational materials and go to komen.org. And you will be able to find that exact sciences also as information, um, at two sites, I will say one is onco type. I Q. Dot com. So that’s onco type O N C O T Y P E I q.com as well as a page specifically for breast cancer patients, which is called my breast cancer treatment.org.

All one word, my breast cancer treatment.org. We have great resources. Coleman has great resources. I would recommend starting at any of these places to help guide you through the conversation you can have with your physician for best shared, decision-making be part of the process and be well-informed so that the best decisions can be made between you and your physician to get.

[00:17:04] Adam Walker: Well, that’s a great, uh, admonition there, and I really appreciate you joining us on the show, just breaking all this down in a way that we can, we can follow and understand, and really understanding how these tests can really help lead to better outcomes, better treatments. So, uh, Dr. Russell, thank you so much for joining us today.

Thank you to Exact Sciences for supporting this Real Pink podcast. For more information about Exact Sciences, please visit their website at exactsciences.com. For more information about genomic testing in breast cancer, please visit www.komen.org.

Thanks for listening to Real Pink, a weekly podcast by Susan G Komen. For more episodes, visit RealPink.com. 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.