When breast cancer cells test positive for estrogen receptors, it’s called estrogen receptor-positive (ER-positive) breast cancer. It means that estrogen is fueling the growth of the cancer. It’s one of several important characteristics of breast cancer that help determine the best treatment options.
In this article, we’ll examine the role of hormone receptors in breast cancer, how they affect treatment, and a general idea of what you can expect.
ER-positive breast cancer is the most common type of breast cancer diagnosed today.
According to the American Cancer Society (ACS), about
How many ER-positive cases are also PR-positive?
Progesterone receptor-positive (PR-positive) breast cancer means that the cancer is using progesterone as fuel. According to BreastCancer.org, about 65 percent of ER-positive breast cancers are also PR-positive.
Estrogen and progesterone are the two hormones associated with breast cancer. If the cancer has either or both receptors, it’s also known as hormone-positive or HR-positive breast cancer. Breast cancers that test negative for both hormone receptors are HR-negative.
Breast cancer is also checked for a protein called human epidermal growth factor receptor 2, or HER2. Having too much of this protein can help cancer grow and spread. These cancers are called HER2-positive or HER2-negative.
Breast cancer can also be triple-positive or triple-negative.
If your doctor suspects breast cancer, you will likely have a biopsy to test for cancerous cells. If there is cancer, your doctor will also test the cells for characteristics that include what receptors, if any, are present on the surface of the cancer cells.
The outcome of this testing is important when making treatment decisions. What treatment options are available is highly dependent on the test results.
If you have ER-positive breast cancer, your cancer cells grow in the presence of the hormone. Estrogen occurs naturally in the body. Drugs that interfere with estrogen’s ability to promote cancer cell growth are used to treat ER-positive breast cancers.
Hormones are chemical messengers that circulate in the bloodstream. Hormone receptors are proteins located in and around breast cells. When the corresponding hormone binds to a receptor, it tells the cells how to grow and divide.
In the case of breast cancer, these receptors allow abnormal cells to grow out of control, which results in a tumor.
What are estrogen and progesterone receptors?
Estrogen and progesterone are two hormones that can help breast cancer grow. These hormones bind to estrogen and progesterone receptors.
Following a breast biopsy, a pathologist will perform a test called an immunohistochemical staining assay (IHC) on the tissue sample. The test can detect the presence of estrogen and progesterone receptors.
Hormone receptor status provides a lot of information on how the cancer is likely to behave. It’s also a key factor in determining the best possible treatment.
HR-positive breast cancer typically responds well to hormone therapy. These therapies block the production of the hormones or interfere with their effects on breast cancer cells. On the other hand, HR-negative breast cancers don’t respond to hormone therapy, so other treatment options will be more effective.
Your outlook depends on the stage of your cancer when it’s discovered. Cancer is staged by number, starting with 0 and going to 4. Stage 0 is the very beginning and stage 4 is the last stage, also called the metastatic stage, because it’s when cancer has spread to other areas in the body.
Each number reflects different characteristics of your breast cancer. These characteristics include the size of the tumor and whether the cancer has moved into lymph nodes or distant organs, like the lungs, bones, or brain.
Research on survival statistics for people with breast cancer tends to separate participants into categories of women and men.
Survival statistics of women with the major subtypes of breast cancer — such as ER-positive, HER2-positive, and triple-negative — are grouped together. With treatment, most women with very early stage breast cancers of any subtype can expect a normal life span.
Survival rates are based on how many people are still alive years after they were first diagnosed. Five-year and 10-year survival are commonly reported.
5-year survival rates
According to the ACS, the
|Stage at diagnosis||Percentage living after 5 years|
|localized (hasn’t spread outside the breast)||99 percent|
|regional (has spread to nearby tissue or lymph nodes)||86 percent|
|distant (has spread to distant organs)||28 percent|
|all stages combined||90 percent|
One thing to note is that these statistics included women with the more aggressive HER2-positive and triple-negative cancers.
These numbers reflect women diagnosed between 2010 and 2016. Stage 0 is not invasive cancer and is not included in these survival statistics.
According to the Centers for Disease Control and Prevention (CDC), the
|Stage at diagnosis||Percentage living after 5 years|
|all stages combined||84.7 percent|
These numbers reflect men diagnosed between 2007 and 2016.
There are a few different treatment methods for ER-positive breast cancer. All women who have ER-positive breast cancer will be recommended a type of hormone therapy, also known as endocrine therapy. Often, breast cancer requires a combination of treatments.
Hormone treatment aims to prevent estrogen from activating cancer cell growth. This can be accomplished in a few ways, including:
Blocking estrogen receptors
- Selective estrogen receptor modulators (SERMs)
- tamoxifen (Nolvadex)
- toremifene (Fareston)
- Selective estrogen receptor degrader (SERD)
- fulvestrant (Faslodex)
Lowering estrogen levels
- Aromatase inhibitors (AIs)
- anastrozole (Arimidex)
- exemestane (Aromasin)
- letrozole (Femara)
Suppressing ovarian function
- Luteinizing hormone-releasing hormone (LHRH) agonists
- goserelin (Zoladex)
- leuprolide (Lupron)
The specific hormone therapy for you will likely depend on whether you’re premenopausal or postmenopausal. Hormone therapy can start before or after surgery and may continue for 5 years or more.
Most women with early stage breast cancer will have surgery before starting hormone therapy. Surgical options will vary depending on:
- the size of the breast
- your personal preference
- the size of the cancer
You can either have part or all of the breast tissue removed. A lumpectomy removes breast tissue, but not the entire breast. A mastectomy removes the entire breast.
Most women will likely also have one or more lymph nodes removed from under the arm. Depending on what type of surgery you have, you may also need radiation, which uses high energy rays to kill leftover breast cancer cells.
An Oncotype DX test can show whether chemotherapy will be beneficial and reduce your risk of relapse. The test examines 21 genes in cancerous tumors to identify the potential relapse rate.
If you have a low recurrence score, you will likely not need chemotherapy. If you have a high recurrence score, you will likely need chemotherapy, surgery, and hormone therapy.
The Oncotype DX test, which may be paid for by Medicare and most insurance plans, is recommended for women who have early stage breast cancer that is:
Chemotherapy uses powerful drugs, delivered through the veins or taken as a pill, over the course of several weeks or months. These drugs are designed to kill cancer cells.
ER-positive breast cancer has a high chance of being successfully treated, especially when it’s discovered early. A diagnosis at a later stage will have a less positive outlook, but being diagnosed at a later stage is less common.
There are still many treatment options for late stage cancer.
The outlook for women with ER-positive breast cancer is generally good, and there are effective treatments. The chances for a long life are excellent.
Getting a cancer diagnosis and treatment can feel overwhelming, but getting support from others who know what you’re going through can help. Find support from others who are living with breast cancer. Download Healthline’s free app here.