Hormone Receptor Positive Breast Cancer:
A Conversation with Alissa Huston, MD
By Pat Battaglia
Rochester-born Alissa Huston, MD, is a hematology/oncology specialist associated with the University of Rochester whose focus is on breast cancer. A familiar presence to many at the Coalition as a caring oncology provider, an occasional presenter at our educational seminars, and a past recipient of the Hearts and Hands Award, Dr. Huston kindly agreed to share her abundant knowledge regarding hormone receptor positive breast cancer.
Some breast cancer cells have receptors that bind to the hormones estrogen and/or progesterone. These cells need one or both of these hormones to grow. About eighty percent of breast cancer cases are estrogen and/or progesterone receptor positive. While this form of the disease affects many, approaches to treatment vary widely according to individual needs. We thank Dr. Huston for helping to clarify the intricacies of this all-too-common breast cancer subtype.
Question: For the person recently diagnosed who may be learning for the first time that their breast cancer is hormone-receptor positive, it can be a confusing time. What do they need to know about their diagnosis?
Dr. Huston: There are many elements that can be involved in a breast cancer growing, and when we think of one that’s driven by hormones, having that information helps us in tailoring what treatments an individual may receive. Medicines we use to block hormones will be an important part of their treatment plan. Sometimes I use the analogy of a cupcake. It sounds funny, but if you think of a hormone blocking medication as the cake portion, then what else will add benefit on top of it? It’s that icing – how much additional benefit you are going to get from adding chemotherapy.
We can have two estrogen-positive cancers and approach each of them differently. Some people have very little benefit from chemotherapy, and some of the new molecular tests help us in determining that specifically for hormone receptor positive cancers. Estrogen expression is one of the big drivers of breast cancer, and there is a group of medicines that will block those hormones and help provide that benefit to patients.
Question: Do hormone positive breast cancers differ significantly from those in which the growth is not driven by estrogen or progesterone?
Dr. Huston: They can. In terms of hormone receptor positive breast cancers, there are some that more strongly express estrogen and there are some that express it more weakly or behave less like your typical estrogen positive cancer. We know there are some that have some hormone expression but that may not be the big driver of what’s causing that cancer to grow and develop. When I’m talking with patients, I like to think about it in terms of what options we have available for treatment.
When you think about the most common breast cancer subtypes – hormone positive, triple negative, and HER2 positive – this is directing what tools I can use to treat the cancer. In triple negative breast cancer, all our treatments are chemotherapy, although for some patients now, immunotherapy can come into play. In HER2 positive cancers, there are targeted medicines for those receptors. Not every cancer is going to behave the same way and that’s true in every subtype. Everyone is an individual and everyone’s cancer behaves in its own unique way.
That’s often how I think about it – what the characteristics of the cancer are, hormone receptor status being one of those characteristics. There are other factors such as the growth rate, the grade – a whole number of things – that affect how a cancer responds to treatment. I look at the hormone receptors and think, okay, I have certain options as part of my overall plan.
Question: Are there any new treatment possibilities on the horizon for hormone positive breast cancer?
Dr. Huston: Yes. There have been a few clinical trials looking at a class of medications called CDK4/6 inhibitors. Many patients with metastatic breast cancer are familiar with them. There are three of these medicines, and they’ve been studied for quite a number of years in the metastatic setting, showing improvement in responsiveness over time in patients who take them along with the typical anti-estrogen medications like aromatase inhibitors. There have been a few studies looking at patients with early stage disease and whether these medicines can help to further reduce the rate of recurrence. One of the studies is still ongoing. One was mixed in its results, but the third showed a benefit. So there is a subset of patients that are considered higher risk – meaning a higher growth rate of their cancer above a certain threshold with positive nodes and a higher grade – that may benefit from the inclusion of this medicine for two years. It’s called abenaciclib or Verzenio. That’s been a new tool that we can talk about for patients with hormone positive breast cancer; are they eligible for this to help reduce their risk and improve that outcome.
It’s not without side effects but we have a good sense of what those are and how to manage them from our advanced breast cancer patients. It’s not for everybody and it’s approved in a very select subset of patients. We’re certainly waiting on data from some of the other trials.
For molecular tests such as OncotpeDX, we have more and stronger data, and ongoing studies showing that even in node positive patients that are estrogen positive, it can help us more precisely tailor treatment to the individual. All hormone positive cancers aren’t the same. While some may get some benefit from chemotherapy, others will not. Molecular testing may not always be appropriate in every circumstance, but that would be something else for us to talk about with patients.
Question: Considering the hormone-blocking agents that have been in use for a long time, we know they often come with a set of side effects. We’ve developed a program at the Coalition that helps people manage one of the most common side effects of aromatase inhibitors – joint pain – if they experience that.
Dr. Huston: Your program is wonderful. I spend a lot of time talking about aromatase inhibitor side effects with postmenopausal women, as that is the preferred anti-estrogen for them. Joint aches are one of the most debilitating side effects, and fatigue and hot flashes can also be debilitating. But your program has been wonderful and I continually receive great feedback from patients about how it’s helped them. While we have medicines that can also help, the thought of layering medicine after medicine can be overwhelming for many patients who are committing to, at minimum, five years of treatment and probably a little longer.
Looking at the total duration of treatment with aromatase inhibitors, we began treating people for five years, then ten years was better for some, and there was a study released last summer that said seven years seems on par with ten in terms of effectiveness and maybe less in terms of some of the side effects. There are still patients that may benefit from longer treatment but we’re trying to narrow down that timeline. So it’s a matter of having those conversations and figuring out what’s best for an individual.
We recently piloted through the Pluta Integrative Oncology and Wellness Center a small program based on large study that came out a few years ago looking at acupuncture to help reduce joint pain from aromatase inhibitors, and that showed a reduction in pain. Those are ways we can support patients for that duration of time they need to be on treatment.
Tamoxifen can also carry different side effects, but certainly it’s something to talk about with your provider. If you’ve struggled with all three aromatase inhbitors, Tamoxifen may still offer benefit for some patients.
Question: At the Coalition, we often see premenopausal survivors whose oncologists have recommended ovarian suppression in combination with aromatase inhibitors as superior to Tamoxifen, which has typically been used in that age group to block estrogen.
Dr. Huston: There is data to support this, and the strongest data is in the very young patients where chemotherapy was recommended for node positive cancer, although those are the ones that we also have to support too. Because if you’re in your early 30’s and now you’re in menopause, it’s hard to be in that place. But there is a benefit of that combined suppression. We start with what we think is going to offer the best benefit , do all we can to support the patient, and then look at things like Tamoxifen if we need to. It still offers benefit. But it’s hard, especially in our younger patients, where it brings in the conversations about fertility. Those are really important conversations to have when you’re talking about the timeline of treatment.
There is a study that closed a couple years ago that was looking at treating young patients for eighteen months to three years with anti-estrogen therapy and then, if they met certain criteria, coming off treatment to have a family then resuming treatment. We’re waiting on the data from that trial, and that’s an important and hopeful study for our young estrogen positive patients. If we’ve got a large study that backs it up, then we’ve got the data to begin doing this coordinated break and then resuming treatment.
Question: All of these conversations are complex. I’m sure your work is difficult – and heartbreaking sometimes. I’m wondering if there’s something or some person that drew you to your specialty.
Dr. Huston: Yes. I was initially drawn to oncology when I was in my training. I feel so honored to do what I do. I also had family experiences with a grandmother who had gone through breast cancer and advanced breast cancer when I was very young. She lived far away, but knowing and watching and understanding at some level what she had gone through impacted me. I also had the priviledge to work with Dr. Jennifer Griggs when I was a resident participating in a rotation that she created. I was drawn to the patients she cared for and at the end of four weeks, I knew that breast cancer was what I wanted to focus on. So that was my introduction.
Question: At the end of the day, what gives you hope?
Dr. Huston: I always look at what I do as a partnership with myself and my patient, and trying to look at everyone as an individual, and to do what’s right for them. And there’s hope in the midst of everything. Hope can take many different faces. At times it can be very hard and challenging and conversations can be very difficult. I feel that I get so much from what I do; from those that allow me to care for them