Treatment for HER2-positive breast cancer

If you have HER2 positive breast cancer, your treatment options will depend on several factors, such as the stage of the cancer (early or metastatic) and the status of the tumor hormone receptors .

HER2 positive tumors can also be estrogen receptor positive ( triple positive breast cancer ). However, the tumor receptor status can change (from positive to negative or vice versa). As a result , the treatment plan recommended by your oncologist may change.

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About 20-25% of newly diagnosed breast cancers are believed to be positive for a genetic mutation that amplifies the HER2 gene. The mutation causes the gene to make too many HER2 / neu proteins (or just HER2 proteins).

In normal amounts, these proteins act as receptors that tell breast cells how much to grow (and when to stop). When there is a mutation, the excessive production of HER2 proteins stimulates the growth of breast cancer cells.

HER2-targeted therapies include Herceptin (trastuzumab), Perjeta (pertuzumab), and T-DM1 (trastuzumab emtansine), which is marketed under the brand name. Kadcycla.

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Early stages

Treatment for early-stage HER2-positive breast cancer is similar to treatment for HER2-negative breast cancer, but usually also includes a drug that targets HER2, such as Herceptin .


Usually, a lumpectomy or mastectomy is recommended to remove the tumor in an early stage of breast cancer. Radiation therapy may also be recommended before (neoadjuvant) or after (adjuvant) surgery. Chemotherapy is usually not required at this stage.

If the tumor is DCIS (stage 0) or has a favorable genetic profile, additional treatment (adjuvant therapy) may not be necessary after tumor removal .

Adjuvant therapy is generally recommended for large tumors and lymph node-positive tumors (stage II) and for tumors that invade the surrounding tissue and spread to the lymph nodes (stage III) .

Metastatic cancer (stage IV) has specific treatment protocols and does not always require surgery .

Hormonal therapy

If the tumor is estrogen receptor positive , hormone therapy is recommended. If someone is receiving chemotherapy, hormone treatment can be started after the chemotherapy ends.

For premenopausal people, tamoxifen is usually the first choice. Aromatase inhibitors can be added if someone is postmenopausal. If a premenopausal person needs to take aromatase inhibitors, ovarian suppression therapy, ovarian ablation, or, in rare cases, oophorectomy may be recommended to lower estrogen levels.

People with early stage breast cancer who are premenopausal and at high risk may want to discuss ovarian suppression with their doctor. Research shows that, in some cases, aromatase inhibitors are associated with slightly higher survival rates than tamoxifen.


Depending on the stage of the cancer, tumor size, lymph node involvement, and genetic test results, adjuvant chemotherapy may be recommended. Treatment usually begins one month after the lumpectomy or mastectomy and lasts for four to six months .

HER2 Targeted Therapy

Before HER2-targeted treatment, HER2 tumors were considered aggressive cancers. With the advent of targeted therapy, survival rates have improved.

In 1998, Herceptin (trastuzumab), The FDA approved the first drug that directly targeted HER2. Oncologists usually start this drug before trying other treatments.

A decade after its introduction, Herceptin was joined by two more HER2-targeting drugs: Perjeta (pertuzumab) and T-DM1 (trastuzumab emtansine).

In 2017, Nerlynx (neratinib) was also approved for the treatment of people with HER2-positive early breast cancer after treatment with Herceptin.

According to a 2016 study, when neratinib (a tyrosine kinase inhibitor) was added to standard breast cancer therapy, complete response rates were higher than in people who received Herceptin plus standard therapy .

Tykerb (lapatinib) is another tyrosine kinase inhibitor that can be used after treatment with Herceptin or other HER2 medications .

Radiation therapy

For people opting for a lumpectomy, radiation therapy is generally recommended after surgery. For tumors with four or more positive lymph nodes, radiation therapy after mastectomy is often considered .

Tumors with one to three positive lymph nodes are in the relative gray zone. In this case, you should talk to your doctor and radiation oncologist about the possible benefits of treatment.

Bone modifying drugs

The addition of bisphosphonate therapy has been considered for early-stage breast cancer, as it may reduce the risk of bone metastases .

Advanced stages

In metastatic breast cancer, the goal of treatment is usually systemic therapy aimed at controlling the disease. Surgery and radiation therapy are considered topical treatments and are used primarily for palliative purposes only (to relieve pain and / or prevent fractures) .

A biopsy of the metastatic site and reexamination of the receptors is recommended to ensure that the HER2 status and estrogen receptor status have not changed.

First-line therapy for HER2-positive advanced breast cancer depends on the results of receptor studies. For people who are HER2 positive, one of the HER2-targeted therapies described above is generally used.

If the tumor is also estrogen receptor positive, hormone therapy, HER2 therapy, or both may be considered. Chemotherapy can also be used for several months.

If the tumor has already been treated with Herceptin (trastuzumab) as adjuvant therapy and the disease returns within six months after discontinuation of adjuvant trastuzumab therapy, T-DM1 is usually the second-line drug of choice .

Perjeta (pertuzumab) can be used in combination with trastuzumab and a taxane in patients with early-stage breast cancer who have already received Herceptin as an adjuvant, but who are considered to have a high risk of recurrence.

For cancer that progresses after trastuzumab and taxane in a metastatic setting, T-DM1 is the preferred option. If the person has not previously been treated with Herceptin, a combination of Herceptin, Perjeta, and a taxane can be used.


If the cancer progresses despite these treatments, a combination of Tykerb (lapatinib) and Xeloda (capecitabine) may be tried, as well as other chemotherapy or hormone therapy regimens .

Brain metastases

HER2 positive breast cancer is more likely to spread to the brain and liver than HER2 negative tumors. It appears that Herceptin (and possibly Perjeta) can cross the blood-brain barrier and reduce the size of brain metastases.

For people with bone metastases, bone-modifying drugs, such as bisphosphonates, can not only reduce the risk of fractures, but also improve survival .

Integrative procedures

Many people ask about alternative therapies when they are diagnosed with breast cancer. There are no proven "natural cures" for breast cancer, and no alternative treatments have been found to effectively treat the condition.

However, there are several comprehensive cancer treatments that can help people cope with the disease. symptoms of the disease and side effects of cancer treatment (eg, fatigue , anxiety, nausea, peripheral neuropathy , etc.).

Some integrative therapies that have been specifically studied for women with breast cancer include yoga , meditation , massage , and acupuncture .

A 2017 study found that women with metastatic breast cancer who were HER2 positive responded to Herceptin more favorably than women who were HER2 negative and did not meet treatment criteria.

Clinical trials

There are clinical trials looking at breast cancer surgery, chemotherapy, and radiation options, as well as studies comparing various hormonal and HER2-targeted treatments.

Myths of clinical trials persist, but they can sometimes offer a better treatment option. Your oncologist will explain how clinical trials work and whether they are right for you.

Get the word of drug information

Herceptin has forever changed the way HER2-positive cancers are treated and what people can expect when they are diagnosed. Herceptin and other HER2-targeted therapies have been shown to reduce the risk of early recurrence in HER2-positive breast cancer and improve survival in HER2-positive metastatic breast cancer.

The treatment recommended by your healthcare provider will depend on several factors, including the stage of the cancer; the size and spread of tumors; and if you have tried other treatments. Your oncologist will explain the options available to you and help you decide which treatment is right for you.

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