What Could Metastatic Breast Cancer Genetic Testing Advances Mean for You?

What Could Metastatic Breast Cancer Genetic Testing Advances Mean for You? from Patient Empowerment Network on Vimeo.

How do genetic testing advances impact metastatic breast cancer patients? Dr. Julie Gralow discusses these advances, including treatment developments, and the importance of retesting over time. 

Dr. Julie Gralow is the Jill Bennett Endowed Professor of Breast Medical Oncology at the University of Washington, Fred Hutchinson Cancer Research Center, and the Seattle Cancer Care Alliance. More about this expert here.

See More From INSIST! Metastatic Breast Cancer

Related Resources:

 

How Genetic Mutations Affect Metastatic Breast Cancer Disease Progression and Prognosis

Factors That Guide a Metastatic Breast Cancer Treatment Decision

How Can You Advocate for the Best Breast Cancer Care?

 

Transcript:

Katherine:                  

What advances have there been in testing?

Dr. Gralow:                

Well, it used to be – just going back a couple of years ago – that we didn’t do a lot of this genetic testing or genomic profiling of the tumor because we didn’t have many – the term is an “actionable mutation.” So, if we found something, would we do something with it? Did we have a drug we could use to do it? But, more and more and more, even in breast cancer, we’re finding actionable mutations that would drive therapy.

For example, in estrogen receptor positive breast cancer, we have a new class of targeted therapies called PI 3-kinase inhibitors – a drug called alpelisib or Piqray was approved in the last couple of years in that category – and it only is effective in estrogen receptor positive breast cancer that has a mutation in the PI 3-kinase gene. So, that would be something we’re looking for in the tumor’s genes, and actually, we need to know that there’s a mutation to even get the drug approved for treatment because it doesn’t work if you don’t have that mutation.

Increasingly, we’re finding some changes that can happen in the estrogen receptor gene and the HER2 gene, interestingly, so that you can have estrogen receptor expressed on your tumor, but over time, that tumor might develop an estrogen receptor mutation so that it stops responding to certain drugs that target the estrogen receptor.

And so, that’s called an ESR1. That’s the name of the estrogen receptor gene – an ESR1 mutation – and that would tell me probably not going to respond as well to a drug in the class we call aromatase inhibitors, but might respond better to a drug in the class that we call the selective estrogen receptor degraders like fulvestrant or Faslodex, is the name of a drug in that class.

We’re also finding that you can have what we call activating mutations in HER2, and they can be present whether the tumor overexpresses HER2 or not, and we’ve got some ongoing clinical trials looking at if the tumor doesn’t have extra HER2 on its surface – so, it doesn’t have extra HER2 protein, but at the gene level, it’s got an activated HER2 gene – we can use certain types of HER2 therapy to treat it, and we’re testing that right now in clinical trials.

So, could we even use some HER2 drugs even though technically, the tumor would be classified as HER2 negative? So, fascinating increasing information that we’re understanding, and I also mentioned before we can inherit mutations in genes such as BRCA1 and 2, but fascinatingly, the tumor can acquire those mutations. Even if we didn’t inherit a mutation, we can see mutations in the BRCA1 and 2 gene – we call those somatic as opposed to germline mutations. So, “germline” means it’s in every cell in your body, but “somatic” means the tumor somehow acquired this over time.

And so, we’ve done – we just presented some very early results of a trial, and we’re expanding this trial, looking at if you didn’t inherit a BRCA1 or 2 mutation, so technically, you don’t qualify for a PARP inhibitor, but if the tumor acquired a mutation and we can prove that with testing the tumor’s DNA, then we have seen responses from these PARP inhibitors, so that opens up another whole class of treatments, and there are other DNA repair genes that actually may be qualified as well that we can inherit or that can be acquired by the tumor.

So, more and more, we’re doing this genomic profiling, and it is leading to results that would give us possible treatment options.

Katherine:                  

Dr. Gralow, the goal of this program is to provide the confidence and tool for patients to advocate for the essential tests to get best care personalized to them. Are there specific tests that patients should make sure they have?

Dr. Gralow:                

Well, there are a lot of assays out there to do this genomic profiling or genetic testing of the tumor, so I don’t promote any one. Various institutions do it and do it well, various companies do it, but I think every metastatic patient should have the tumor looked at in this kind of profiling.

I also think every metastatic patient should advocate for having a biopsy of their cancer, and if a biopsy cannot be done safely in the recurrence, then see if they could get a liquid biopsy – have blood drawn to find it. So, I think that patients should be asking about this. Sometimes, insurance won’t always cover it, and so, my job as a treating physician is to advocate for that, to do an appeal.

More and more, because we have so many actionable mutations in breast cancer now, I’m not having insurance decline, but occasionally, it does, and then it’s our job as the healthcare providers to make the case that yes, this will impact the patient, and yes, it should be covered by insurance.

What Are Essential Genetic Tests for Metastatic Breast Cancer Patients?

What Are Essential Genetic Tests for Metastatic Breast Cancer Patients? from Patient Empowerment Network on Vimeo

Genetic tests can help guide metastatic breast cancer care. Dr. Julie Gralow discusses essential genetic tests for metastatic breast cancer, and how results impact treatment decisions.

Dr. Julie Gralow is the Jill Bennett Endowed Professor of Breast Medical Oncology at the University of Washington, Fred Hutchinson Cancer Research Center, and the Seattle Cancer Care Alliance. More about this expert here.

See More From INSIST! Metastatic Breast Cancer

Related Resources:

 

How Genetic Mutations Affect Metastatic Breast Cancer Disease Progression and Prognosis

Metastatic Breast Cancer: Debunking Common Misconceptions

What Could Metastatic Breast Cancer Genetic Testing Advances Mean for You?

 


Transcript:

Katherine:                  

For a patient to get diagnosed, what are the essential tests?

Dr. Gralow:                

So, we’re talking about metastatic breast cancer here, and in the U.S., maybe up to 10% or slightly less of breast cancer is technically Stage 4 or metastatic at diagnosis. That means at the time we first found it in the breast, it had already spread beyond. So, an important thing that we’ll do with a newly diagnosed breast cancer is especially if there are a lot of lymph nodes are involved or the patient has symptoms that might say there’s something in the bone, liver, or lung is staging.

So, we’ll use scans – maybe a CAT scan, bone scan, or PET scan – and we will look at whether the disease has gone beyond the breast and the lymph nodes, and if so, where. So, maybe 8-10% of breast cancer diagnosed in the U.S. already has some evidence that it has spread beyond the breast, but the most common way that metastatic breast cancer happens is that a patient was diagnosed possibly years and years ago, treated in the early-stage setting, and now it comes back, and that is the most common presentation for metastatic breast cancer, and sometimes that can be due to symptoms.

As I said, if it comes back in the bone, maybe that’s bone pain. If it’s in the lung, it’s a cough. There are symptoms. Sometimes, it’s because we’ve done a blood test or something and we find some changes there.

And so, when a breast cancer has recurred, it’s really important to document that it’s really breast cancer coming back, first of all, and so, if we can, we generally want a biopsy, and we want to stick a needle in it if it’s safe to do, and look and verify that it looks like breast cancer, and also, it’s really important that we repeat all those receptors that we talked about from the beginning because it can change.

So, a cancer up front 10 years ago could have been positive for estrogen receptor, but the only cells that survived – mutated, changed – were estrogen receptor negative, so what comes back could be different. So, it’s really critical to get that biopsy, repeat the estrogen/progesterone receptor and HER2, and also, in an ideal world, now that it’s 2020 and we’re moving more toward genomics, to do a full genomic profile and look for other changes and mutations that could drive our therapeutic options.

So, staging, knowing where the cancer is, getting a good baseline by understanding where it is and how big it is so that we can follow it and hopefully see that it’s responding to treatment, and then, repeating all of the biology components so that we know what the best options are for treatment are really critical.

Katherine:                  

Right. How can patients advocate for a precise breast cancer diagnosis, and why is that important?

Dr. Gralow:                

Well, all those things I just mentioned are key. Knowing exactly where it is so that we can monitor it – for example, if the cancer has come back in the bones, we would add what we call a bone modifying agent, a drug like zoledronic acid or denosumab – Zometa or Xgeva – which can suppress bone destruction from the cancer, but if it’s not in the bone, we wouldn’t add that.                                   

And, we want to have a good look everywhere so that we can see if it’s responding because sometimes, the tumor can respond differently in one area than another. Also, I think it’s really important to know what your treatment options are by doing that biopsy, getting a full panel, and looking at potentially hundreds of genes that could be mutated, deleted, or amplified so that we know what our treatment options are.

And, we’re not going to use all the treatment options up front, so it’s helpful for knowing that if this treatment doesn’t work or is too toxic, what are the second-line or third-line options? So, we make sure that there’s what we call good staging up front so we know where the cancer is, and then we make sure that we’ve looked at it as best we can in 2020 with all the genomics.

 That would give us the best chance of being tailored – individualized – to the tumor. Sometimes, if we can’t biopsy it, like with a needle that would go into a liver spot, then increasingly, we’re looking at what we call liquid biopsies, and that can be drawing the blood and seeing if we can find parts of the tumor, whether it be the DNA or the RNA that’s floating around in the blood, and sometimes we can get that information out of the blood as well.