Chemotherapy is one of the most common treatment methods for fighting breast cancer. Typically used in combination with surgery, chemotherapy helps to kill breast cancer cells whether they reside within the breast or have managed to escape throughout the body.
What is Chemotherapy?
Chemotherapy refers to the use of drugs to treat cancer. For many years, women with a tumor measuring at least 1 centimeter in diameter were offered chemotherapy. A growing understanding of breast cancer genetics have improved our ability to identify who can benefit from chemotherapy and to deliver an optimal chemotherapy regiment.
There are many chemotherapy drugs and combinations of drugs used to treat breast cancer. Each drug works in different ways, but most induce apoptosis, or cell death, by interfering with the division of cancerous cells.
Adjuvant vs. Neoadjuvant Chemotherapy for Breast Cancer
Chemotherapy can be administered before or after surgery to treat breast cancer. Adjuvant chemotherapy is delivered following surgery. Adjuvant chemotherapy is typically administered as insurance to attack any cancerous cells that remain in the body.
Neoadjuvant chemotherapy, or chemotherapy administered prior to surgery, has become more common in recent years. Ongoing research suggests that many women who respond to neoadjuvant therapy experience relatively high cure rates. There are several advantages to neoadjuvant chemotherapy.
- Immediate treatment to the whole body, including breasts, lymph nodes and bloodstream.
- Potential for less aggressive surgery to the breast and lymph nodes.
- Response to chemotherapy can be evaluated by observing shrinkage of cancer.
Chemotherapy for Breast Cancer by Genomic Type
Breast cancer is caused by genetic mutations. As the medical community’s understanding of breast cancer genetics evolved, a new system for classifying breast cancer evolved. This system has identified for main subtypes of breast cancer based on genetic analysis. These subtypes include Luminal A, Luminal B, Triple-Negative and HER2-positive.
Breast cancer subtype influences the decision to use chemotherapy, the specific type of chemotherapy used and when to use chemotherapy.
- Luminal A cancer cells are similar to healthy breast cells. These are slow-growing cancers that are unlikely to respond to chemotherapy.
- Luminal B cancers are more aggressive than Luminal A cancers. While chemotherapy can benefit women with Luminal B cancer, individual patients’ risk for systemic spread should be considered. For instance, hormone therapy is preferred over chemotherapy in women with a cancer that has not spread to the lymph nodes and that is smaller than 1 centimeter in diameter.
- Triple-negative cancers are fast-growing and more likely than others to occur in younger women. Chemotherapy is often administered prior to surgery in order to shrink tumors before their removal.
- HER2-positive breast cancers are aggressive and can spread to the bloodstream quickly. In women with HER2- positive cancers, cancer cells have HER2 receptors in their surfaces. Several types of chemotherapy and other systemic therapies that target HER2 receptors have been developed.
Risks of Chemotherapy
Each patients respond to chemotherapy differently. When patients know they have a chance to benefit from chemotherapy, they are generally willing to undergo any temporary side effects. Common temporary side effects include fatigue, hair loss, nausea and risk for infection. These side effects can often be managed and many patients will not experience any of these besides hair loss.
Although small, there is a risk for permanent damage from chemotherapy. Patients diagnosed at an early age can suffer from reproductive health complications. Certain systemic therapies, which are being used less frequently, can also increase risk for other cancers.
The physicians at Breastlink work with you to develop a treatment plan that accommodates your personal goals and values. We strive to provide an optimal outcome while also limiting the potential for side effects associated with surgery and chemotherapy.