Also welcome news for patients with estrogen receptor–positive (ER+) breast cancer, recently presented data suggest a survival benefit for some patients by extending endocrine therapy to 10 years, rather than stopping at 5 years. But the question remains, which subset of ER+ patients stands to benefit?
Physicians have a variety of choices on the assays to apply to their patients. There are many genetic expression profiling and expanded immunohistochemistry (IHC) tests to guide the adjuvant therapy of women with breast cancer, including Breast Cancer Index (BCI), MammaPrint, Oncotype DX, and Prosigna. In this installment of Interview With the Innovators, we focus on BCI – the only validated test available to physicians and patients that provides guidance on the benefit of extending endocrine therapy for an additional 5 years.
BCI is a biomarker test that assesses distinct biological pathways for breast cancer. It predicts both early recurrence (0-5 years) and late distant recurrence (5-10 years) as well as the likelihood of benefit from extended endocrine therapy. About two-thirds of breast cancer patients are ER+, and the risk of late distant recurrence is a concern, with more than 50% of recurrences occurring after 5 years.
The publishers of PMO had the unique opportunity to discuss the utility of BCI with Dr Stephen Malamud and Dr Susan Boolbol of Mount Sinai Beth Israel Hospital about their collaboration as a medical and surgical oncology team to employ a test such as BCI in the treatment decision-making process for patients. What follows are highlights from their thoughtful exchange. To view the video of their discussion, please visit www.personalizedmedonc.com.
PMO Thank you for talking with us today about guiding the adjuvant therapy of women with breast cancer using the Breast Cancer Index (BCI). To begin, can you describe the circumstance in which you would use this test?
Dr Malamud At the time of diagnosis, a woman with breast cancer will come to the office to make that critical decision on how to move forward with their adjuvant therapy. There are many parameters we will use to ascertain risk and determine what the best treatment might be.
First and foremost is the clinical presentation in the stage of the cancer. Second comes a variety of these biomarkers that we now use to help differentiate who needs chemotherapy, hormone therapy, or combinations of those therapies and predictions in terms of outcome of treatment and the benefits of those same therapies.
The markers we have considered to date include the estrogen or progesterone receptor by IHC, but more importantly, as we enter the era of personalized medicine, we look at the genomic analysis of the tumor to decide what needs to happen in the first 5 years. If they are hormone positive, do they need chemotherapy in addition to their hormone therapy? Secondly, what should we do when those patients have survived without a recurrence for their first 5 years and we need to decide how to move forward? We now have genomic analysis for both of those scenarios. The most critical new question is what to do at that fifth year when we have been relatively stuck with information that tells us that only a small percentage of women will benefit from an additional time on anti-estrogen therapy beyond the fifth year.
The Breast Cancer Index (BCI), a newly developed second-generation genomic assay, will tell us who is likely to benefit with the additional therapy (Figure 1). Other women, who have a low likelihood of benefit, may be absolved from continuing therapy. We can look at BCI to determine not only the risk of recurrence but the likelihood of benefit from additional therapy. We determine the risk of recurrence over those next 5 years, defined as low or high risk, and use that information as a segue to the discussion of the potential additional benefit of therapy. Based on data from the MA.17 study, those patients who have anything other than a low BCI predictive are more likely to benefit from an additional 5 years of therapy.
Dr Boolbol This field has changed enormously over the past 20 years. We wouldn’t think of treating a patient now without information from the initial biopsy, IHC of estrogen and progesterone, and Her2 status. And now we need genomic information when we’re discussing the potential benefit of chemotherapy. We now have assays to help guide us in treatment decisions.
We have several clinical trials showing that 10 years of endocrine treatment is better than 5 years. That benefit for the overall population of women with breast cancer is relatively small, single digits. But, with BCI, we now have an assay to give us more information, to personalize the treatment for individual patients. We can tell a patient, we’ve run this assay on you and you are not likely to derive much benefit from an additional 5 years or, you will likely derive benefit. It’s a paradigm shift of great benefit to patients.
PMO Can you discuss the importance of the multidisciplinary treatment team and the value of gene expression profile tests to the team?
Dr Boolbol A critical part of taking care of women with breast cancer is the team approach. A surgeon cannot take care of a breast cancer patient alone, a medical oncologist cannot do it alone, and a radiation oncologist cannot do it alone. It really is a working, functioning team that needs to take care of the individual patient. In doing that, part of the surgeon’s job as potentially the first interaction with the patient is educating the patient on how their team functions and all the treatment options, from surgery to systemic therapy.
Considering these new genomic tests and patients’ involvement with the multidisciplinary team, it’s important that the patient understands that there are tests that the treatment team uses for early and late treatment. The patient should anticipate interaction with all of the team members, and that will make a difference to their overall care. In fact, studies have shown that patients treated at high-volume centers, meaning centers that take care of a lot of breast patients, treat patients in a multidisciplinary fashion, and the patients have better outcomes.
Dr Malamud Dr Boolbol and I are very fortunate in that when patients come in for their first visit after they’ve had a diagnosis established, we have the opportunity to see patients together or within several days of each other. Patients really pick up on that, and they understand that there is a multidisciplinary collaborative effort to maintain their health and continue their care for years. I’m not going to take care of you only for these couple of months and then I’m gone and will turn you over to this person. It is a team that continues for at least 5 years and usually more. That kind of interaction is appreciated, and having us both in the same room sometimes at the same time where you’re talking about the surgical aspects and the postoperative care and introducing the concept of genomic testing, prognostic testing, hormonal therapy, chemotherapy, etcetera. The treatments segue into my role quite nicely, and then if at the end of the day they still have some questions, the fact that we can assure them that the following day their case is going to be presented at an even larger, multidisciplinary session again affords some relief because now they’re going to have 20-odd heads discussing their case, hopefully getting a check mark of approval to what we’ve already discussed.
Dr Boolbol As I tell patients, breast cancer is too big for them to handle alone. They need support. And it’s the same thing for those of us caring for them. As a multidisciplinary team we support each other in order to take care of the individual patient. It’s important for patients to know how the team interacts and functions. For example, since I am the first one seeing the patient postoperatively and seeing their pathology first, I’m the one who orders any genomic test that will aid in the decision of chemotherapy.
As the patient moves through treatment and follows up with me and with Dr Malamud, then we start discussing other tests that will aid in the decision of long-term treatment, specifically endocrine treatment such as BCI.
PMO BCI touts the unique ability to predict risk of both early and late recurrence, as well as likelihood of benefit from extended endocrine therapy in early ER+ breast cancer. In your experience, are these performance characteristics unique for BCI compared with the other assays?
Dr Malamud Yes, BCI testing has become an important adjunct in our care of patients, especially as we make decisions about therapy beyond 5 years. Normally it’s been the paradigm in the adjuvant treatment of breast cancer that the endocrine treatment continue for 5 years, and we’ve been hard-pressed to find data to support going past the 5-year mark.
Recently, however, several trials, including the ATLAS, MA.17, and others, have shown that there is an advantage for some women to go on with extended adjuvant treatment beyond the fifth year.
The BCI test can help us decide which of those women are actually likely to see benefit from an additional 5 years. If one looks at those trials that were done years ago and now beyond the 10-year mark, the absolute benefit for most of the women if one looks at the mean is only about 5% or 6%, which means that most women do not benefit from being on 5 years of additional therapy. Our goal is to try and isolate those patients who are going to benefit from treatment and not give extended 5 or 10 more years of hormonal therapy to those women who are not likely to realize benefit.
So BCI is a test that separates those patients who are more likely to benefit from those who are unlikely to benefit. It offers a genomic profile of the tumor using a genomic panel completely distinct from the one that they may have had 5 years earlier and looks at the likelihood of benefit from continuing that treatment.
We are able to explain to the patient that this test is designed to help tell us whether or not there’s more therapy that’s likely to work for them in preventing this disease from coming back. It will help tell us whether or not you need to be treated beyond that fifth year or if we can just stop and be comfortable with that idea.
The idea of being able to stop potentially problematic hormonal therapy that they’ve endured for the 5 years prior is an amazing relief for these women who do not have to continue therapy. And for the women who are likely to benefit from continuing therapy, knowing that there is something that’s going to help them if they are at high risk is again almost of the same benefit.
Dr Boolbol If you compare how we treated patients 10 years ago to now, it’s vastly different. That was really just a cookie-cutter mold. You have breast cancer, it’s this size, it’s this stage, this is what you get. We still have a long way to go, but we really have moved so far past that, and it’s because of these genomic tests.
If the patient is not likely deriving any benefit and this treatment is not helping them, why would we put them at risk for any side effect? I only want to give a patient treatment if they will benefit. The studies show that there is a small benefit for longer than 5 years of treatment, up to 10 years of endocrine treatment. When we exclude the low-benefit patients and treat the patients who stand to benefit, we’re making strides in treating their disease.
When we look at chemotherapy, we see the same thing. When we look at the overall benefit of chemotherapy, it was only about 4% for the individual patient. But when you remove the low-risk patients and you just treat the high-risk patients with chemotherapy, you’re now seeing benefits of over 25%. That’s what we’re doing now in the extended endocrine phase of their treatment.
If we eliminate the low-risk patients who really are not likely to derive any benefit, and we’re only treating the high-risk patients who are likely to benefit, that’s where we’re going to see an enormous difference in outcome.
Dr Malamud To take data from 10,000 people and point to the 3% or 5% that may benefit and guess that you might be in that 5% is now an unnecessary gamble. That’s 5 years of treatment with the side effects of anti-estrogen therapy for a potential 5% difference in outcome. It is a big deal for a 40-year-old to continue another 5 years of tamoxifen or for a 60-year-old to continue another 5 years of an aromatase inhibitor (AI). There can be consequences of the treatments that may be in excess of that 5% to 6% difference in the long-term survivorship, or disease-free survivorship.
Dr Boolbol It’s no longer one size fits all – we’re really treating the individual patient. Ten years ago I could tell a patient with a tumor measuring greater than 1 centimeter they were getting chemotherapy. We’ve moved into the era of genomic testing that looks at the individual cancer to determine if the patient will benefit from chemotherapy.
Now my discussion with a patient includes educating them on a test to help with the decision for chemotherapy, and at 4½ to 5 years we’ll be implementing another test to help us with the decision of continuing endocrine or anti-estrogen treatment for another 5 years.
Dr Malamud BCI testing has now become a critical part of our decision making in that 4-, 4½-year mark and provides another opportunity to educate the patients. It behooves us as physicians to stay educated because breast cancer patients come in with that information. I relish that discussion because this is something that’s going to help us decide who gets treated.
PMO Please describe the prognostic and predictive characteristics of this assay. Dr Malamud The Breast Cancer Index has 2 unique qualities. The first is that it is prognostic in terms of the recurrence of breast cancer in those second 5 years of disease-free state, and secondly, it will give us a prediction in terms of the value of the additional hormonal therapy for the additional 5 years. Those data are actually the only validated data for any test in demonstrating likelihood of benefit for some patients in treating beyond 5 years (Figure 2).
Those data actually come from a very large multicenter trial, a randomized trial done from the NCIC in Canada called the MA.17, which looked at continued adjuvant therapy, continuing an AI after the first 5 years of tamoxifen. When that patient population was analyzed, there was a demonstrable benefit for those patients who received the additional AI therapy 2 years or more. In fact, at the 2-year mark, when the code was broken, it already was such a dramatic difference that the patients were unblinded and offered cross-over, which has been a criticism of that protocol.
But when one looks at that protocol and looks at the outcome, again the results were relatively small for the overall population. When that tumor population was looked at and classified by BCI analysis, it was quite clear there were 2 groups – those that were benefiting and those that were not. Those that were benefiting had a 15% or more, perhaps even 16% difference in terms of likelihood of benefit, or likelihood of recurrence versus the group that was statistically not getting any benefit at all.
PMO How has BCI changed the discussions you have had with your patients? Dr Malamud Using those data and the discussion with the patient regarding risk and benefits, we’re able to separate out those patients who are more likely to be getting an increased benefit from that additional time on drug. Without that, we were obliged to offer at least the discussion regarding continued adjuvant therapy, and patients would look at those data relatively quizzically and wonder whether or not they were going to be in that small subgroup of patients who are actually benefiting and whether or not converting from a tamoxifen to an AI was worth that little incremental gain and the toxicities associated with the AIs. The Breast Cancer Index has made that discussion not only objective but more acceptable at the patient’s level.
Dr Boolbol You hit on some key points, especially that this now gives us objective evidence. BCI allows us to have this objective discussion with our patients and move away from that one size fits all to where we have a validated test to show us that you are not likely to benefit or that you are likely to benefit. And we know that 50% or more of patients are of low benefit for extended treatment, and that makes a big difference to those patients.
Dr Malamud To be able to point to the other bar graph and say look, you’re going to be one of the women who’s more likely to benefit from additional therapy; you’ve already done the first 5 years, let’s go the full-court press. We have the evidence that you’re in the potential group that’s going to benefit from treatment, let’s move forward.
That kind of objective information will oftentimes convince the patient to get off the fence and to move forward. That’s incredibly important for us now at that fifth year where we’re sort of stuck in terms of weighing the benefits without data. The Breast Cancer Index has provided the data that allow for an objective discussion.
Dr Boolbol We know with endocrine treatment compliance is an issue with most of our patients. Patients have heard for years that you take 5 years of endocrine treatment and you’re done. But then we’re asking for another 5 years because we have studies to show that an additional 5 years may be of benefit, many patients think “I’m not doing this another 5 years. I’ve endured side effects from this for 5 years.”
But if we tell a patient, listen, we’ve done the BCI test for you, and we know you are likely to benefit from this, they may be much more likely to be compliant with the next 5 years of treatment.
Dr Malamud If one has that information and it’s there in black and white, and anyone tells them that this test was devised just for this purpose and there is a strong likelihood that you’re in this category that will benefit from treatment, it turns an hour-long discussion as to risks and benefits into something much more manageable and focused such that the patient who thought, “Gee whiz, I’m all finished,” now can at least be given some objective data that there is value for more.
PMO Extending endocrine therapy past 5 years is a notion recently studied in the ATLAS and MA.17 trials. Can you please discuss this development, the role BCI plays in making the decision of whether to continue therapy, and the impact on patients?
Dr Malamud BCI occupies a pivotal role now in our decision making when a woman receiving hormone adjuvant therapy reaches the fourth to fifth year of their treatment. That has been the paradigm and the therapy for women with hormone-positive breast cancer such that they remain on anti-estrogen therapy for 5 years. We’ve been struggling to find that population of women who will benefit from extended adjuvant, meaning continuing that anti-estrogen therapy onto the fifth and now into the tenth year.
Several clinical trials showed definitively that there is improvement in a population of women to be treated beyond that fifth year. Both the ATLAS and MA.17 trials demonstrate an improvement somewhere between 3% and 6% for the overall population. However, the woman sitting in front of you at that fourth to fifth year is not really interested in the general population of 5000 or more women. They really want to know what the likelihood is that they’re going to benefit, and pointing out that there is a 3% to 6% difference is not helpful to me because it also means that they’re also at risk for all the complications of treatment that take place beyond the fifth year; whether that’s a continued menopausal symptomatology of tamoxifen or the potential risk of osteoporosis, and other complications of the aromatase inhibitors.
It’s also worth noting that BCI can be used to revisit a previously made treatment decision. For example, if you have a 42-year-old patient, 7 years postdiagnosis, who opted to discontinue tamoxifen 2 years ago at the 5-year point, you can obtain the BCI test to provide reassurance of that treatment decision. If the test result for this patient shows a high likelihood of benefit from an additional 5 years of therapy, the patient can be offered to restart endocrine treatment. The reverse is also true; you may have a patient who decided to continue anti-estrogen treatment for an additional 5 years, but obtaining the BCI test at the seventh year yielded a result of low likelihood of benefit. For this patient, I may recommend discontinuation of therapy at this point.
Dr Boolbol I think that the Breast Cancer Index and really the ATLAS trial and the MA.17 trial are pivotal changes or paradigm shifts in how we’re taking care of patients. Prior to the release of these studies I would tell a patient that they were on endocrine treatment for 5 years. Again, this goes on during their initial consult as part of their overall treatment plan. Now I tell them that they’ll be on it for 5 to 10 years depending on the results of this test.
I do not know whether they will benefit from extended therapy or not. I have trials to say yes, the population at large benefits, but sitting in front of that patient, they’re really not interested in the population at large. They’re interested in what will benefit them, and I now can sit there and say we have a test, BCI or Breast Cancer Index, that we’ll be doing around 4½ years to tell us and give us that information of whether you are likely to benefit from extended therapy.
If there is a low likelihood of benefit, I may recommend that you don’t need it. No one wants to be taking a medication with potential side effects for little to no benefit. If there is benefit, you will want to take it, and that’s really what we’ve gotten down to. It’s a paradigm shift in how we’re treating patients with breast cancer (Figure 3).
Dr Malamud We always think that it’s relatively easy to convince somebody to take their medication that’s going to be potentially lifesaving for the first 5 years. Compliance in the first 5 years is critical. Convincing someone who’s already endured some considerable discomfort for those first 5 years to consider going on for another 5 years can be difficult. It’s nice, in fact, it’s critical to have this information that justifies the continuation of therapy.
PMO Can you share your thoughts on how BCI affects patients in terms of their notions of survivorship or the psychological impact of stopping versus continuing treatment?
Dr Malamud The Breast Cancer Index is an important tool to help at the decision point at that 4½- to 5-year mark. Clearly, it’s important for the patient to know whether additional therapy will be beneficial for them over the next 5 years. But probably, almost of equal importance, is the reliance on Breast Cancer Index in helping us decide to stop after 5 years.
A breast cancer patient, when she hits that 4½-year mark, is looking toward that goal line as the time that they can finally stop treatment. They need to go on with their life off of medication, be assured their disease is under control and likely to stay under control for the next 5 to 10 years.
In the past, we were reluctant to do that without testing that could help us, especially after the recent trials of the ATLAS or MA.17 and the extended adjuvant trial to tell us more might be better. But more is only better in a few patients. Being able to tell a patient with more confidence that I think it is safe to stop, that I think it’s safe to go on with your life without additional medication, that it’s safer to perhaps not have any of these side effects that are destined or at least likely to happen over these next 5 years is very important.
I often tell the patient they’re a survivor from the minute they meet me. But that 5-year mark has become a goalpost for many women with breast cancer and, frankly, for many people with all sorts of cancer, that 5-year mark has been their unofficial guidepost, and now being able to actually tell them in an objective way that after the fifth year, I think it’s safe to stop. You don’t need to go on. Breast cancer is a scary disease for many women, and stopping therapy is every bit as difficult as continuing treatment and being able to show them with reliance that their likelihood of recurrence is small and their likelihood of benefit is equally small gives us the ammunition to support that decision.
Dr Boolbol It’s interesting how patients fall into 1 of 2 camps, and as a surgeon, at the 4-, 4½-year mark this discussion really is ramping up where you have the patient who cannot wait to get off their endocrine treatment and they’re marking it on their calendar. And then you have the other camp of patients that this is really their crutch, and they feel like taking this pill everyday is really helping them – it’s saving their life. We really do now have objective data with BCI to help them through this period at the 5-year mark – we now can say this will continue to help you or this is not likely to give you any additional benefit.
And it helps both camps of patients, because for the women who really feel as though this pill is making an enormous difference and they never want to stop it, we now have a test in BCI to say we’ve run this test and we know that the likelihood of benefit is small for you. At that point the risk/benefit ratio switches. There may be more risks than benefits. That helps them.
For the other patients where the benefits outweigh the risks, that helps them. So really, every step along the way we as physicians are weighing the risk/benefit profile along with the patients to help determine the best, most ideal treatment for them.
Dr Malamud The best survivorship with the best quality of life. That’s what we’re trying to do.
PMO How does the use of this test (BCI) impact patient confidence in their treatment plan and ensure adherence to medication? How difficult is it to explain gene expression profiling and BCI to patients and how this technology will impact their care?
Dr Boolbol It comes down to risk/benefit. If we have a test result telling us that there’s low likelihood of benefit to continued treatment, the patients, knowing that this is a validated test, are going to go along with that. And the reverse is true. If we have a test telling us that they will derive benefit from continued treatment, although they may not be thrilled about continuing endocrine treatment for another 5 years, they will willingly go along with it and are more likely to be compliant.
Dr Malamud For the 5 years prior we’ve talked about survivorship and getting through the treatment. We tell our patients to win the battle, fight the battle today to survive the next couple of years so when the next test or next treatment becomes available, you’re there to participate.
Had we not been in clinical trials, had we not stored your tumor, had we not survived these 5 years, we wouldn’t be having this discussion, so here we are, here’s the information, and it is individualized.
Dr Boolbol We have to remember it’s validated, predictive data, and that’s critically important. I talk to patients about short term and long term and we want to get through the short term so that we have the long term, and that’s really what it comes down to.
PMO How can payers be educated on the value of these technologies to ensure patient access and cost reimbursement?
Dr Malamud Medicare has recently provided coverage for patients receiving testing with the Breast Cancer Index. This is clearly appropriate in my mind, and I would certainly support that it extends onto the other private insurers because, frankly, anyone receiving hormonal therapy, whether they’re Medicare eligible or not, should have the opportunity for this sort of test to be applied to them when they hit the appropriate time frame. Medicare is often the first to adopt new technologies and new treatments, but they’re also a signpost for the third-party coverage to look with a critical eye at the test and appropriately adopt them into their treatment plans as well.
Clearly, if one looks at the advantages to them, the Breast Cancer Index score that would indicate a patient should come off of therapy is advantageous not only to the patient in terms of their side effects and risks, but also advantageous to the insurer to avoid having not only to pay for the course of the drugs over the next 5 years but also to potentially deal with risks and complications over those 5 years to come.
Dr Boolbol I think that insurance coverage really goes back to personalized medicine and now we have coverage for BCI from Medicare, it really seems as though every insurance company out there should follow suit. Just as we want to individually take care of our patients, insurance companies should want the same. There is no medication without potential side effects, and limiting access to a test such as BCI that’s out there and available to tell us whether or not a patient will benefit from therapy or withhold coverage really does not make any sense and it is not in the patient’s best interest.
PMO What are the next steps in comprehensive personalized medicine for patients with breast cancer.
Dr Malamud As we move forward in the treatment of women with breast cancer, we will continue to see increasing use of a personalized approach. We’ve seen personalization of treatment, first in the development of the estrogen and progesterone receptor for those women who would benefit from hormone therapy. After that came Her2 testing to figure out who required anti-Her2 therapy. Now we have genomic testing that looks at the production and expression of genes associated with risk of recurrence and value of endocrine therapy in years 5-10. And now with the Breast Cancer Index, helping us to decide what to do when they hit that fifth-year mark.
There are a variety of other genomic tests out there to determine the interactions or potential resistance mechanisms for chemotherapy, resistance mechanisms in Her2, mTOR inhibition, PI3 kinase. There are companies where you can send tumors for complete genomic analysis to find actionable mutations with the hope that if there’s a mutation for which we have an appropriate drug, we can use that drug to target that mutation.
Dr Boolbol The way in which we treat patients 10 years from now will be completely different from what we’re doing today. Systemic issues, local treatment of breast cancer, how we do surgery, when we do surgery, what options we’re offering the patients, all these will be very different 10 years down the road.
I think that we’re going to be taking a minimally invasive approach to surgery such as cryoablation as opposed to excising the patient’s cancer in the operating room. We’re making advances in all of the arenas of how we treat breast cancer.
Radiation, for instance, there will be fewer patients who receive radiation. We’re also moving into the era of determining who will benefit from radiation rather than just treating every patient who has undergone breast conservation with radiation.
In every discipline of our multidisciplinary team, we’re making advances in the treatment of breast cancer, all taking a personalized approach. If you look at genetic testing, we’ve made incredible advances; so many advances that we don’t have answers to everything that we know right now. That’s one of the things that clinical trials will help us with.
PMO Thank you both very much for your time today, and our best to you and your continued success in your treatment of patients with breast cancer.