Table of ContentsView AllTable of ContentsHER2-Low Targeted TherapyHow Precision Treatment WorksOther Breast Cancer TreatmentsRisks and Side EffectsImpact on Outcomes
Table of ContentsView All
View All
Table of Contents
HER2-Low Targeted Therapy
How Precision Treatment Works
Other Breast Cancer Treatments
Risks and Side Effects
Impact on Outcomes
For those with breast cancer,human epidermal growth factor receptor 2 (HER2) statusis an important classification that allows for targeted treatment. HER2 is a protein associated with normal cell growth found in some breast tumors.
If a tumor has a lot of HER2 on the surface, it is consideredHER2-positive, and if it has none, it is HER2-negative. But, there is also a gray area. If it only has some, this is labeled asHER2-low. Treatment can be targeted to this hormone receptor status.
Until 2022, if someone hadHER2-low breast cancer, treatment was limited since approaches that targeted HER2 weren’t successful in these tumors.
A targeted treatment for HER2-low breast cancer was approved in 2022.Enhertu (trastuzumab deruxtecan T-DXd) delays disease progression longer and has improved survival rates. This is a big step forward from the days when people with breast cancer with low amounts of HER2 received standard treatment options such aschemotherapyor endocrine(hormone) therapy.
Daniel Llao Calvet / Getty Images
As part of this article, you will learn what targeted therapy for HER2-low breast cancer has to offer, what you need to know about how precision treatment works and how this impacts outcomes, the risks and side effects of HER2-low specific treatment, and other breast cancer treatment options.
Targeted Therapy for HER2-Low Breast Cancer
This approval was based on study results that showed that those with previously-treated metastatic HER2-low breast cancer were progression-free of cancer for significantly longer, with a more extended period of overall survival than those who underwent chemotherapy.
But this approach will only be used after other approaches are tried. Your oncologist may recommend the use of Enhertu in these circumstances:
Enhertu is a form of targeted therapy known as an antibody-drug conjugate. The drug has two parts that work together to target cancer cells.
One part of Enhertu is anantibody(immune protein) called trastuzumab that attaches to HER2 on the surface of the tumor cells. HER2 can be found in healthy cells but tends to be found in large amounts on the surface of some cancer cells. By targeting HER2, the treatment mainly affects cancer cells.
With this approach, the chemotherapy is, in effect, targeted mainly at cancer cells, mostly sparing the healthy ones.
Chemotherapy
This approach relies on the use of cancer-killing agents. These are injected or infused into the bloodstream and, from there, travel throughout the body. These drugs interrupt cancer cell growth and affect other fast-growing cells in healthy tissues.
Chemotherapy may be given before surgery to shrink tumors and help to keep cancer from returning. Or, it may be administered after tumor removal to proactively mop up any cells that may have traveled elsewhere.
Is Enhertu Chemotherapy?Enhertu is a drug with a component that can target HER2 receptors associated with some types of cancer, as well as an attached chemotherapy agent to kill these cancer cells.The chemotherapy agent is primarily delivered to cancer cells rather than affecting healthy cells, which differs from traditional chemotherapy agents.
Is Enhertu Chemotherapy?
Enhertu is a drug with a component that can target HER2 receptors associated with some types of cancer, as well as an attached chemotherapy agent to kill these cancer cells.The chemotherapy agent is primarily delivered to cancer cells rather than affecting healthy cells, which differs from traditional chemotherapy agents.
Radiation
Withradiation treatment, high-energy particles disrupt breast cancer tumors. The idea is to use these particles to destroy cancer cells. Typically, radiation treatment is used after tumor removal, such as alumpectomy, to ensure cancer doesn’t return. It may also be used aftermastectomy(breast removal) if the tumor is particularly large or has spread elsewhere.
Different types of radiation treatment may be tried, including:
Hormone Therapy
Since some breast tumors can grow as a result of exposure to hormones, it can help to reduce the amount of estrogen and progesterone that are circulating in the system. For example, in around 7 out of 10 cases, exposure to estrogen can cause breast cancer tumors to grow.By blocking these effects, hormone treatments can help in a variety of ways.
Hormone therapy can be used to:
Risks and Side Effects of HER2-Low-Specific Treatment
While Enhertu treatment offers a lot of upsides, it’s also important to be aware that it does bring some risks. Enhertu can have the following side effects:
If adverse reactions are mild and resolve in a matter of weeks, such as asymptomatic pneumonia, it may be possible to resume treatment with the same dosage or to reduce this somewhat. But if the adverse reaction is severe, such as developing a case ofcongestive heart failure, the medication may have to be discontinued.
How Does Precision Treatment Impact Outcomes?
For some, the use of Enhertu can make a big difference. While this treatment cannot cure cancer, it can buy time and extend survival.
Those in the clinical study group who received this targeted medication were able to avoid disease progression for about 10 months, with an overall survival rate of 23.4 months.Meanwhile, those who were given chemotherapy only remained cancer free for around five months, with a survival rate of 16.8 months.
Summary
Targeted HER2-low breast cancer medication has provided new treatment options for those with this condition. The medication, known as Enhertu, targets cancer cells and delivers medication to these to kill the tumors.
While this therapy can be effective, it is tried after other treatments, such as chemotherapy, hormone treatments, or radiation. When the targeted treatment is given, it can extend survival for many.
Understanding Your Breast Cancer Pathology Report
12 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Lai HZ, Han JR, Fu X, Ren YF, Li ZH, You FM.Targeted approaches to HER2-low breast cancer: current practice and future directions.Cancers (Basel). 2022;14(15):3774. doi:10.3390/cancers14153774Food and Drug Administration.FDA approves first targeted therapy for HER2-low breast cancer.American Cancer Society.Chemotherapy for breast cancer.American Cancer Society.Hormone therapy for breast cancer.Modi S, Jacot W, Yamashita T, DESTINY-Breast04 Trial Investigators, et al.Trastuzumab deruxtecan in previously treated HER2-low advanced breast cancer.N Engl J Med. 2022;387(1):9-20. doi:10.1056/NEJMoa2203690.National Cancer Institute.Enhertu may be preferred therapy for some metastatic breast cancers.Cancer Research UK.Chemotherapy for breast cancer.American Cancer Society.Radiation for breast cancer.Cancer Research UK.Hormone therapy.Enhertu.Understanding potential risks.AstraZeneca Canada Inc.Product monograph. Enhertu.National Cancer Institute.Enhertu improves survival for metastatic “HER2-low” breast cancer.
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Lai HZ, Han JR, Fu X, Ren YF, Li ZH, You FM.Targeted approaches to HER2-low breast cancer: current practice and future directions.Cancers (Basel). 2022;14(15):3774. doi:10.3390/cancers14153774Food and Drug Administration.FDA approves first targeted therapy for HER2-low breast cancer.American Cancer Society.Chemotherapy for breast cancer.American Cancer Society.Hormone therapy for breast cancer.Modi S, Jacot W, Yamashita T, DESTINY-Breast04 Trial Investigators, et al.Trastuzumab deruxtecan in previously treated HER2-low advanced breast cancer.N Engl J Med. 2022;387(1):9-20. doi:10.1056/NEJMoa2203690.National Cancer Institute.Enhertu may be preferred therapy for some metastatic breast cancers.Cancer Research UK.Chemotherapy for breast cancer.American Cancer Society.Radiation for breast cancer.Cancer Research UK.Hormone therapy.Enhertu.Understanding potential risks.AstraZeneca Canada Inc.Product monograph. Enhertu.National Cancer Institute.Enhertu improves survival for metastatic “HER2-low” breast cancer.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Lai HZ, Han JR, Fu X, Ren YF, Li ZH, You FM.Targeted approaches to HER2-low breast cancer: current practice and future directions.Cancers (Basel). 2022;14(15):3774. doi:10.3390/cancers14153774Food and Drug Administration.FDA approves first targeted therapy for HER2-low breast cancer.American Cancer Society.Chemotherapy for breast cancer.American Cancer Society.Hormone therapy for breast cancer.Modi S, Jacot W, Yamashita T, DESTINY-Breast04 Trial Investigators, et al.Trastuzumab deruxtecan in previously treated HER2-low advanced breast cancer.N Engl J Med. 2022;387(1):9-20. doi:10.1056/NEJMoa2203690.National Cancer Institute.Enhertu may be preferred therapy for some metastatic breast cancers.Cancer Research UK.Chemotherapy for breast cancer.American Cancer Society.Radiation for breast cancer.Cancer Research UK.Hormone therapy.Enhertu.Understanding potential risks.AstraZeneca Canada Inc.Product monograph. Enhertu.National Cancer Institute.Enhertu improves survival for metastatic “HER2-low” breast cancer.
Lai HZ, Han JR, Fu X, Ren YF, Li ZH, You FM.Targeted approaches to HER2-low breast cancer: current practice and future directions.Cancers (Basel). 2022;14(15):3774. doi:10.3390/cancers14153774
Food and Drug Administration.FDA approves first targeted therapy for HER2-low breast cancer.
American Cancer Society.Chemotherapy for breast cancer.
American Cancer Society.Hormone therapy for breast cancer.
Modi S, Jacot W, Yamashita T, DESTINY-Breast04 Trial Investigators, et al.Trastuzumab deruxtecan in previously treated HER2-low advanced breast cancer.N Engl J Med. 2022;387(1):9-20. doi:10.1056/NEJMoa2203690.
National Cancer Institute.Enhertu may be preferred therapy for some metastatic breast cancers.
Cancer Research UK.Chemotherapy for breast cancer.
American Cancer Society.Radiation for breast cancer.
Cancer Research UK.Hormone therapy.
Enhertu.Understanding potential risks.
AstraZeneca Canada Inc.Product monograph. Enhertu.
National Cancer Institute.Enhertu improves survival for metastatic “HER2-low” breast cancer.
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