Triple-Negative Breast Cancer: How We’re Learning to Treat It More Effectively

Triple-Negative Breast Cancer: How We’re Learning to Treat It More Effectively

About 20% of people with breast cancer have a type called triple-negative breast cancer (TNBC). 

It usually has a worse outlook than other breast cancers. It also tends to affect non-Hispanic Black women and women under 40 more often. But it can be harder to treat because some common cancer treatments, like anti-hormone and anti-HER2, don’t work with TNBC.

In the WebMD webinar “Triple-Negative Breast Cancer: How We’re Learning to Treat it More Effectively,” Kevin Kalinsky, MD, explained how TNBC is different and how new treatments are giving hope.

Most people with TNBC were interested in either empowering themselves with information about their type of cancer or choosing a treatment plan.

More than half of respondents said spending quality time with family and friends is the kind of self-care that interests them most as part of a cancer treatment plan.

“Do older people get triple-negative breast cancer? Is treatment different for them than for younger women who get it?”

“How does TNBC impact the ability to have children? How about its impact on breastfeeding?”

We can see triple-negative breast cancer in older people as well. It’s important for us to define what we mean by “older.” For instance, over the age of 70.

The most common subtype of breast cancer in general is hormone receptor-positive, HER2-negative breast cancer. The prevalence of having this form, I think, is even higher if you’re over the age of 70. However, we also see people with TNBC in that subgroup.

As we get older, we may also have other health issues. Treatment depends on the health of the person. We make an individual treatment plan for each person. If we have a very healthy person who is older, we’ll often have a similar approach to a younger individual.

As for its impact on having children: With chemotherapy during early-stage breast cancer, you can take a medicine that tells your brain to tell your ovaries to stop making estrogen. It’s safe to do this, and we know that it can preserve fertility. For premenopausal people, this is always something that we bring up. Often, we have a person see fertility doctors, too.

We like for there to be a window from the time a person with TNBC has surgery to the time they try to get pregnant. That’s about 2 years.

For people with TNBC who have metastatic disease, meaning it’s spread to other parts of the body, we don’t suggest they get pregnant. This is because we give therapies that aren’t safe during pregnancy. 

In terms of breastfeeding, it depends on what’s going on at the time. If you’re actively getting chemotherapy, we usually don’t recommend breastfeeding. 

Immunotherapy is new. We don’t quite know the effect on fertility yet, but experts continue to study this.

“What do you recommend for addressing the mental health impacts of having TNBC?”

“What are the top self-care tips you recommend for someone with TNBC? Do they make a difference in prognosis?”

“What are the most important precautions in the first 5 years of TNBC diagnosis and treatment to prevent it from coming back?”

It’s normal in our clinic to ask how people are doing. Some centers have more availability of therapists or psychiatrists than others. There are also social workers and spiritual health experts at some places.

Don’t underestimate this. It’s important to let your provider know if you’re struggling.

In terms of self-care, information is power. It’s important to go to well-established sites that give accurate information. It’s also important to find a provider with whom you feel comfortable – somebody you trust and somebody who communicates in a helpful way.

Especially on that first appointment, bring a loved one, friend, or family member with you because you may have a lot of anxiety. Having someone with you to hear and collect information can be critical. Also, think about some non-Western medical options. Experts can guide you in these to help complement some of the treatments that you may receive.

Give yourself grace, especially at the beginning when things can be very stressful. 

As for precautions, for people with stage I through III TNBC (meaning it hasn’t spread beyond your breasts or nearby lymph nodes), the risk of recurrence is in the first 5 years. After those first 2 years, we take a deep breath. Then, by the end of the 5 years, if there’s not been a recurrence, we can fully exhale.

This is different from patients who have estrogen-driven breast cancer where we can see late recurrences after 5 years.

My general rule of thumb is: If you have a new symptom not otherwise explained that lasts for 2 weeks or longer, let your doctor know.

“Is there any benefit in taking immunotherapy for 2 years post-treatment when there’s no longer detectable cancer?”

“How can someone find clinical trials for triple-negative breast cancer? Are they a good idea to participate in?”

The standard is to take 1 year of immunotherapy for patients who have stage II through III TNBC.

They start immunotherapy with chemotherapy before they go into surgery. Regardless of what we see at the time of surgery, they continue immunotherapy for a full year, including that time before surgery.

But we haven’t evaluated 1 versus 2 years. For people who don’t have anything within the breast or the lymph nodes at the time of surgery, the standard is to continue immunotherapy. But we don’t know if that’s necessary. There’s a large study that’ll look into this to make sure we’re not overtreating people.

As for clinical trials, I can’t stress how important it is to do them. The advancements that we have today are purely because of clinical trials. To find these, there is a website, clinicaltrials.gov. You’re able to type in information like “triple negative” to help find one for you. The site will also find ones that are close to you.

It means your breast cancer doesn’t have these three receptors:

  • HER2
  • Estrogen
  • Progesterone

“Estrogen and progesterone are hormones that we all make, and those receptors are doors that let hormones come in and feed a cancer cell,” said Kalinsky. HER2 is a gene that helps breast cancer cells grow. 

There are pills that target estrogen and intravenous (IV) and subcutaneous (under the skin) treatments that target HER2. But these don’t work for TNBC. “Without those receptors, giving treatments that block estrogen or HER2 are not effective,” said Kalinsky.

Some drugs were recently approved to treat people with early-stage and metastatic TNBC. They include:

Immunotherapy. This intravenous (IV) treatment (which means it goes into your veins) tells your body to attack cancer. It’s been approved for many forms of cancer. 

Pembrolizumab (Keytruda) is now approved for people with metastatic TNBC whose tumors express a protein on the cancer cell called PD-L1.

For stage II through III TNBC (which means if there’s a positive lymph node under your arm or your cancer is greater than 2 centimeters), doctors often give immunotherapy and chemotherapy before surgery.

PARP inhibitors. These are approved if you have metastatic breast cancer. They’re oral drugs (meds you take by mouth) and targeted therapies that block the enzyme known as PARP. This helps stop cancer that has BRCA mutations from repairing its DNA and surviving. These treatments are approved for people who have BRCA mutations.

If you have HER2-negative breast cancer (which includes TNBC) and BRCA mutation, you might take olaparib (Lynparza) for a year. Your doctor might also prescribe talazoparib (Talzenna).

“In one study, we clearly saw that there was a delay in growth of the cancer if people received a PARP inhibitor compared to chemotherapy,” said Kalinsky.

Antibody drug conjugates. This is a combination of chemotherapy and monoclonal antibodies. The antibodies link up with the protein on breast cancer cells and deliver the chemotherapy straight to the cancer. 

“You can think about this like a GPS drug,” said Kalinsky. 

“The antibody targets this protein and then directly delivers the chemotherapy to the cancer cell instead of giving chemotherapy to the veins.”

The drug, called sacituzumab govitecan (Trodelvy), was approved for TNBC that was treated but has spread to other parts of your body or that can’t be removed with surgery.

One study compared this drug to chemotherapy. “We saw such notable effects, not only for delays in terms of the time that it took for the cancer to grow, but also people were living twice as long,” said Kalinsky.

Watch an online replay of  “Triple-Negative Breast Cancer: How We’re Learning to Treat it More Effectively.”

Watch other free WebMD webinars by leading experts on a variety of topics. 

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