Neoadjuvant Therapies
What is neoadjuvant therapy?
In some cases, treatment with chemotherapy, HER2-targeted therapy or hormone therapy may be given before breast surgery. When treatment is given before surgery, it’s called neoadjuvant therapy or preoperative therapy.
Neoadjuvant therapy drugs are often the same as adjuvant therapy drugs (those used after surgery).
Before you begin neoadjuvant therapy, talk with your health care provider about possible side effects and how to manage them.
What to expect before neoadjuvant therapy
A needle biopsy is used to diagnose breast cancer. It removes a small amount of tumor tissue.
A clip is often placed in the tumor bed during the biopsy so the tumor can be found later when you have surgery. This clip can be seen on an X-ray. It’s usually removed during surgery.
The biopsy tissue is tested for biomarkers, such as hormone receptor status and HER2 status. These factors determine the type of neoadjuvant therapy that will offer the most benefit.
Neoadjuvant chemotherapy
If your treatment plan includes chemotherapy, neoadjuvant chemotherapy may be an option as a first treatment.
Chemotherapy has the same effectiveness whether it’s given before surgery or after surgery. The timing of chemotherapy around surgery does not affect survival.
However, for some people, neoadjuvant chemotherapy can change their surgical options. Neoadjuvant chemotherapy may be able to shrink a large tumor enough so a lumpectomy (plus radiation therapy) becomes an option instead of a mastectomy [10].
Neoadjuvant chemotherapy may also be given to people who have enlarged lymph nodes in the underarm area due to the spread of breast cancer to these lymph nodes. Neoadjuvant therapy can shrink the lymph nodes. This makes the surgery to remove the nodes easier.
Most tumors respond to neoadjuvant chemotherapy. If a tumor doesn’t respond to one chemotherapy drug regimen, a different combination of drugs may be used, or it may be best to proceed with surgery.
In some cases, response to neoadjuvant chemotherapy can help guide treatment after breast cancer surgery.
Types of neoadjuvant chemotherapy regimens
Neoadjuvant chemotherapy regimens are the same as the standard regimens used after surgery. Most are anthracycline-based or taxane-based therapies.
For HER2-positive tumors, neoadjuvant therapy usually includes a combination of chemotherapy and the HER2-targeted therapy drugs trastuzumab (Herceptin) and pertuzumab (Perjeta).
For some triple negative tumors (those that are hormone receptor-negative and HER2-negative) at high risk of recurrence, neoadjuvant therapy may include the immunotherapy drug pembrolizumab (Keytruda).
Learn more about neoadjuvant trastuzumab and pertuzumab.
Learn more about neoadjuvant pembrolizumab.
Learn more about chemotherapy drugs.
Learn more about HER2 status.
Breast cancer recurrence and survival with neoadjuvant chemotherapy
A meta-analysis that combined the results of 12 studies found no difference in rates of breast cancer recurrence or overall survival in women who had neoadjuvant chemotherapy versus those who had adjuvant chemotherapy [163].
Learn more about lumpectomy versus mastectomy and survival.
Triple negative breast cancer
Some people with triple negative breast cancer have cancer remaining in their breast after neoadjuvant chemotherapy. In these cases, treatment with the chemotherapy drug capecitabine after breast cancer surgery may lower the risk of recurrence and improve survival [10].
| For a summary of research studies on neoadjuvant chemotherapy, visit the Breast Cancer Research Studies section. |
Neoadjuvant hormone therapy
Neoadjuvant hormone therapy is only used to treat hormone receptor-positive (estrogen receptor-positive and/or progesterone receptor-positive) breast cancers.
Neoadjuvant hormone therapy (usually with an aromatase inhibitor in postmenopausal women) may change a person’s surgical options. It may be able to shrink a large tumor enough so a lumpectomy plus radiation therapy becomes an option instead of a mastectomy [10].
In some cases, response to neoadjuvant hormone therapy can help guide treatment after breast cancer surgery.
Neoadjuvant hormone therapy is an option for some postmenopausal women, including those who can’t have chemotherapy due to health problems or advanced age, and for some women who have a very low risk of breast cancer recurrence [10].
Survival is the same whether you start taking hormone therapy before surgery or after surgery.
Under study
Hormone receptor-positive breast cancers can be treated with neoadjuvant chemotherapy or neoadjuvant hormone therapy. Researchers are studying how to choose between neoadjuvant chemotherapy and neoadjuvant hormone therapy when treating hormone receptor-positive breast cancers.
| For a summary of research studies on neoadjuvant hormone therapy, visit the Breast Cancer Research Studies section. |
Learn more about hormone receptor status.
Neoadjuvant therapy for HER2-positive breast cancers
For HER2-positive breast cancers, neoadjuvant therapy usually includes a combination of the HER2-targeted therapy drugs trastuzumab (Herceptin) and pertuzumab (Perjeta).
Survival is the same whether you start taking HER2-targeted therapy before surgery or after surgery.
Trastuzumab
Trastuzumab is given through an IV into a vein or by an injection every 3 weeks.
Trastuzumab is given with neoadjuvant chemotherapy, but not at the same time as the chemotherapy drug doxorubicin (Adriamycin).
Whether you will continue to get trastuzumab after surgery depends on the pathology of the tissue removed.
Pertuzumab
Pertuzumab may be used in combination with trastuzumab and chemotherapy for neoadjuvant therapy.
Whether you will continue to get pertuzumab and trastuzumab after surgery depends on the pathology of the tissue removed.
Under study
Other HER2-targeted therapy drugs, including antibody-drug conjugates such as trastuzumab deruxtecan (Enhertu) and ado-trastuzumab emtansine (Kadcyla, T-DM1, trastuzumab emtansine), are under study for neoadjuvant therapy for HER2-positive breast cancers [149].
Ado-trastuzumab emtansine is already FDA-approved for use as an adjuvant (after surgery) treatment for early breast cancer.
Learn about HER2 status and prognosis.
Neoadjuvant therapy for triple negative breast cancers
Pembrolizumab (Keytruda)
For triple negative breast cancers at high risk of recurrence, neoadjuvant pembrolizumab (Keytruda) may be given in addition to neoadjuvant chemotherapy.
Triple negative breast cancers are:
Pembrolizumab is given through an IV into a vein every 3 weeks or every 6 weeks for up to one year. You either get a smaller dose every 3 weeks, or you get a larger dose every 6 weeks.
Neoadjuvant pembrolizumab can be given on the same day as neoadjuvant chemotherapy.
After surgery, you will continue to get pembrolizumab to complete one year of treatment.
Learn more about pembrolizumab for early triple negative breast cancer.
After neoadjuvant therapy ends
To check the response to neoadjuvant therapy, you may have several tests including a clinical breast exam, a mammogram, a breast MRI and/or a breast ultrasound.
Surgery is then planned much in the same way as if you didn’t have neoadjuvant therapy.
Pathologic response
After neoadjuvant therapy and surgery, a pathologist will check the breast tissue removed during surgery for a pathologic response.
Pathologic response describes how much of the tumor is left in the breast and lymph nodes after neoadjuvant therapy.
Pathologic complete response
In some cases, neoadjuvant therapy will shrink the tumor so much the pathologist can’t find any remaining cancer. This is called a pathologic complete response (pCR).
Whether or not you have a pCR can give some information about your chances for a breast cancer recurrence, which could change your treatment plan.
Although a pCR is encouraging, it doesn’t mean the cancer will never return. And many people who don’t have a pCR will still do very well.
pCR rates after neoadjuvant chemotherapy are highest among women with tumors that are [164]:
- High-grade
- Hormone receptor-negative (estrogen receptor-negative and/or progesterone receptor-negative)
- HER2-positive, when the neoadjuvant treatment plan includes trastuzumab and pertuzumab
However, neoadjuvant chemotherapy can be effective in treating tumors of any grade, hormone receptor status or HER2 status.
Learn more about tumor grade.
Learn more about hormone receptor status and HER2 status.
Sentinel lymph node biopsy and neoadjuvant therapy
A sentinel lymph node biopsy checks for cancer in the axillary lymph nodes (the lymph nodes in the underarm area).
Sentinel lymph node biopsy is usually done after neoadjuvant therapy, at the time of your breast surgery.
However, it may be done before neoadjuvant therapy begins if the status of the lymph nodes will affect your surgery options or your drug therapy options after surgery [10].
Treatment guidelines
Although the exact treatment for breast cancer varies from person to person, evidence-based guidelines help make sure high-quality care is given. These guidelines are based on the latest research and agreement among experts.
The National Comprehensive Cancer Network (NCCN) and the American Society of Clinical Oncology (ASCO) are respected organizations that regularly review and update their guidelines.
In addition, the National Cancer Institute (NCI) has treatment overviews.
Talk with your health care team about which treatment guidelines they follow.
After you get a recommended treatment plan from your health care team, study your treatment options. Together with your health care team, make thoughtful, informed decisions that are best for you. Each treatment has risks and benefits to consider along with your own values and lifestyle.
Updated 04/12/24
