Extending Life with Immunotherapy: Advances in Treating Triple-Negative Breast Cancer

The August 9, 2022 edition of the National Cancer Institute’s Cancer Currents blog announced the findings of the clinical trial KEYNOTE-355 that examined the benefits of using the immunotherapy drug pembrolizumab (Keytruda) in conjunction with chemotherapy in treating advanced triple-negative breast cancer (TNBC).

The results, published in the New England Journal of Medicine (Cortes et al., 2022), revealed that pembrolizumab in conjunction with chemotherapy was effective in extending the lives of TNBC patients with advanced disease as compared to chemotherapy alone, and the difference was striking. Those who received the drug lived a median of 23 months compared to 16.1 months for the chemo-only group.

Sources: Cancer.gov, Cancer Currents blog

Of course, cancer differs among patients and not all TNBC tumors are the same. The life-prolonging benefits of pembrolizumab were limited to those patients with PD-L1 scores of at least 10; PD-L1 is an immune checkpoint protein, and the score denotes the level of this protein found in cancer tumor cells.

And it’s important to note that while the drug extended life expectancy, it was not yet a cure, which is what we’re all still waiting for.

So there are asterisks associated with these findings, which might be disappointing for those with advanced cancers of this type. But the researchers stressed that this is a very promising outcome.

Consider the advances that have been made. TNBC used to be treated with untargeted therapies, kind of like throwing everything you’ve got at the tumor and hoping that something “sticks”. On the other hand, pembrolizumab is a targeted therapy for this specific subset of TNBC, and that makes a huge difference.

There has been a push to address the complexities of TNBC and large strides have been made in understanding what makes it tick. New therapies are being approved and they are making researches optimistic about eventually being able to cure the disease.

As an example, in April 2021, the FDA approved the use of sacituzumab govitecan (Trodelvy) for the treatment of certain types of TNBC (after conditional approval had been granted in April 2020). As noted in the May 12, 2021 edition of the Cancer Currents blog, sacituzumab is comprised of an “antibody coupled to a more potent form of the chemotherapy drug irinotecan (Camptosar). The antibody binds to breast cancer cells, delivering the chemotherapy directly to those cells.”

There’s good news for some patients with advanced triple-negative breast cancer.

Notably, patients receiving sacituzumab lived a median of 11.8 months longer compared to 6.9 months for those patients receiving the chemotherapy alone. Positive results were also obtained for patients with brain metastases, where the cancer has spread to the brain, who tend to have worse outcomes when treated only with chemotherapy.

There is still so much more to learn. Cancer is a puzzle and researchers have known for some time that the pieces do not yet fit together cleanly. But each one of these advances brings us more effective treatments for TNBC, addressing more specific targets on the tumors. Lifespans are increasing and for many, cancer is taking the form of a chronic disease, not a death sentence.

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REFERENCES

Cancer Currents Blogs

Sacituzumab Govitecan Approved for Metastatic Triple-Negative Breast Cancer, Cancer Currents, May 28, 2020: https://www.cancer.gov/news-events/cancer-currents-blog/2020/fda-sacituzumab-govitecan-triple-negative-breast-cancer

Sacituzumab Govitecan Earns Full Approval for Triple-Negative Breast Cancer, Cancer Currents, May 12, 2021: https://www.cancer.gov/news-events/cancer-currents-blog/2021/sacituzumab-govitecan-tnbc-regular-approval

Pembrolizumab Improves Survival in Advanced Triple-Negative Breast Cancer, Cancer Currents, August 9, 2022: https://www.cancer.gov/news-events/cancer-currents-blog/2022/pembrolizumab-triple-negative-breast-cancer-improves-survival

KEYNOTE-355 Clinical Trial
(as of this posting, the full article is not yet available to non-subscribers)

Cortes et al. (2022) Pembrolizumab plus Chemotherapy in Advanced Triple-Negative Breast Cancer. New Engl J Med, 387, 217-226. 10.1056/NEJMoa2202809

Presence by Touch: A Visualization

Staying present is key for not letting your thoughts take you on a wild ride.

Maintaining presence, however, takes practice so I’m always on the lookout for new ways to imagine the state of being in the “now”. Some of these are simpler exercises than others, but the upside of a more “complex” technique means that all my mental energy remains on staying present instead of, say, worrying whether I embarrassed myself at a party three nights ago.

The following is a visualization and mental exercise rolled into one:

What if only what you’re touching exists and everything else falls into nothingness?

Seated, close the eyes. Breathing deeply, allow everything that is around you to fall away in your mind, leaving only those points where your body makes contact with the surface beneath you.

Imagine that the soles of your feet sit on top of sole-shaped pieces of support material. Your buttocks and thighs contact like-shaped material, as does any place your back rests against your chair. If you touch your fingers to the side of your chair seat, small oval-shaped pieces of material appear where your fingers make contact.

Everything else disappears against a background of light (or darkness, if that is more calming). The chair and floor and even the room you are in? Gone. The point of this visualization is maintaining focus on only what you are physically experiencing at any given moment.

It is a strange sensation to imagine, floating through the ether but still feeling support from the slightest bits of material that touch you. This is the ultimate in being 100% present and turns the concept of object permanence on its head.

You don’t feel it? It doesn’t exist.

Our brain wants to fill in the parts that we can’t see because the brain has formulated an image of what is out there. However, in this practice we try to do the opposite–let go of what we do not have immediate physical evidence for.

This is a good analogy for dealing with thoughts that our brain fabricates based on the expectations that it has. What if we let go of them, if only for a short while, and simply sit in the stillness of what is happening right now?

Wound a Bit Tight? Meditating with Muscle Release

I, like so many people, keep a lot of tension in my neck and shoulders. Some days it feels as though my neck is made of steel, but not in a good way.

The reality is that I don’t even realize how tight those muscles are until I lie down and try to relax.

So I have made a meditation of this for bedtime. Instead of focusing on the sensation of my breath, the focus is on releasing the tension in my neck and upper shoulders.

It may sound like I would not be able to squeeze an entire meditation session out of this, but oh, I can.

Complete release takes focus!

Lying down on my back I inhale, and then with the exhale, I focus on my neck and relax it, releasing the rest of my body along with it. With the following exhale, I do that again. That’s because while I may think that the initial release took care of the tension, there is still tightness there and I really have to work on it mentally to release that.

It’s as though my neck muscles are springs that I can stretch, releasing tension through the exhale, but once I let go (inhale) the “memory” in my muscles tightens them up again.

It helps to imagine my body melting, as if I’m being drawn downward into the Earth.

I can keep going like this, feeling my chin inch slightly towards my chest as the tension releases. Melting into the mattress. The more I release, the more subtle the sensation, yet very satisfying. The more I relax, the more deeply I breathe and everything lets go.

The awareness of what is going on in my body helps so much, but the tension is tenacious. This is not surprising, given how much mental weight my neck and shoulders bear. So it is a dance between releasing and returning to release again. Little by little until I eventually fall asleep.