Once you have been found to have breast cancer, you may be told that chemotherapy is recommended. (Some people call chemotherapy “chemo” for short.) Chemotherapy can be given before surgery to some people, or after surgery, or both before and after surgery. You may be wondering whether chemotherapy will be recommended for you and why.
Not all women with invasive breast cancer need chemotherapy. Whether you need chemotherapy or not is based on several factors, including the spread of your cancer, your tumor grade, receptor statuses, and recurrence score among other.
This post will give you an overview of chemotherapy as well as explain in more detail how the characteristics of your tumor relate to the need to have chemotherapy, or not.
Why is Chemotherapy Given in Breast Cancer?
Chemotherapy is given to decrease the risk of the breast cancer coming back in other parts of your body. Chemotherapy is one type of systemic, or whole-body, treatment for breast cancer.
Surgery removes the tumor from the breast and lymph nodes (the glands that catch cancer cells as they leave the breast), and radiation is given to kill any remaining cancer cells in the breast and lymph nodes that may still be there surgery. But neither surgery or radiation therapy can decrease the risk of the cancer coming back in other parts of your body.
Systemic treatment, including chemotherapy, may reduce the risk of cancer cells later growing in other parts of your body. Chemotherapy goes through your bloodstream and kills cancer cells that may have spread in other parts of the body, such as the bone, lung, and liver.
Chemotherapy cannot prevent the cancer coming back in every person. It can, however, decrease the risk of this happening.
How Do We Decide Whether or Not to Offer Chemotherapy?
Decisions about chemotherapy are made between you and your medical team. We use several things to help us figure out if chemotherapy is likely to help you. Specifically, we include the size of the tumor, the lymph node status (whether or not the lymph nodes have cancer in them), and other features of the tumor described here:
Tumor Size. Breast cancers are measured in centimeters. 1 centimeter is about the size of a green grape cut in half. Tumors are usually not perfectly round. Measurements include the height, the width, and the depth. We talk about the size of your tumor using the biggest measurement. For example, a tumor might measure 3 cm by 2 cm by 2 cm. This would be considered a 3 cm tumor. The tumor size is most important when the lymph nodes are negative.
Lymph Nodes. Lymph nodes are also called glands or just nodes. We have lymph nodes all over our body. They serve as a sort of filter as normal body fluids circulate, catching germs (bacteria and viruses) and even cancer cells. Lymph nodes in your armpit are removed as part of your surgery.
- If cancer is seen in the lymph nodes removed at the time of your surgery, the lymph nodes are said to be positive. If there are no cancer cells in the lymph nodes, the lymph nodes are negative. We are more likely to recommend chemotherapy if the lymph nodes are positive.
Stage: Staging of breast cancer is done based on the size of the tumor, number and extent of lymph nodes involved and spread of cancer cells to other parts of the body other than breast. Staging can vary from Stage I (one) to Stage IV (four). Stage I, II and III refer to breast cancer that has not spread to other parts of the body (meaning, the cancer is limited to only the breast and lymph nodes). Stage IV means the cancer cells have spread to other parts of the body than just breast. Chemotherapy is given with aim to provide cure in Stage I, II and III.
Grade. The grade of the tumor refers to the appearance of the cells compared to normal breast tissue. A tumor that looks a lot like normal breast tissue is grade 1, or low grade. A tumor that is disorganized and does not look like normal breast tissue is grade 3, or high grade. Tumors that are in the middle are grade 2, or intermediate grade. Chemotherapy is more effective in tumors that are higher grade (grade 2 or grade 3).
Hormone receptors. Hormone receptors are proteins on the surface or inside the breast cancer cells. There are two hormone receptors, estrogen receptor (ER) and progesterone receptor (PR). Chemotherapy is more strongly recommended if the tumor does not have either ER or PR.
HER2 status. Some tumors have extra levels of HER2 on them. HER2 stands for Human Epidermal Growth Factor Receptor-2. If your tumor is HER2-positive, chemotherapy is more likely to be recommended.
Lymphovascular invasion (also called angiolymphatic invasion). You will see this referred to by the abbreviation LVI or ALI. Lymphovascular invasion means that cancer cells are seen in the blood vessels or lymph channels in the tumor. Your tumor may or may not have this finding. We are more likely to recommend chemotherapy if your tumor has lymphovascular invasion.
Recurrence score. If your lymph nodes are negative and your tumor has the estrogen receptor, your tumor may be sent for a special test, called a multigene tumor assay. The test can help figure out whether or not chemotherapy is likely to decrease the risk of the cancer coming back. There are several multigene tumor assays. If the result comes back high (meaning there is a high risk of the cancer coming back and that chemotherapy can decrease that risk), we will most likely recommend chemotherapy. If the result comes back low, we will not recommend chemotherapy.
- If you had 1 to 3 positive lymph nodes, your tumor may also be sent for one of these tests.
- These tests are not used in people with tumors that do not have the estrogen receptor.
Does the Kind of Surgery I Have Play a Role in Chemotherapy Decisions?
Surgery removes the cancer only from the breast and the lymph nodes. Decisions about chemotherapy are not related to the kind of surgery you have.
Is it Possible That I Will Not Need Chemotherapy?
There are some people who will not be given chemotherapy.
- If your tumor was half a centimeter (0.5 cm) or smaller and your lymph nodes were negative, chemotherapy will most likely not be recommended unless the tumor was positive for HER2.
- If you have other serious medical problems, the benefits of chemotherapy are small.
- If you had mucinous or tubular carcinoma, chemotherapy is generally not recommended.
- Just a reminder…if your tumor was sent for a recurrence score test (multigene tumor assay) and shows a low risk of recurrence, chemotherapy may not be recommended.
Will I Get Chemotherapy Before or After Surgery?
Most people have surgery first followed by chemotherapy (adjuvant chemotherapy), radiation therapy, and then endocrine therapy (if the tumor was positive for the estrogen and/or progesterone receptor).
Some people have chemotherapy before surgery. If you are offered chemotherapy before surgery, it does not mean that you will get extra treatment. Instead, we’re just switching the order.
Chemotherapy before surgery is called preoperative chemotherapy or neoadjuvant chemotherapy.
Chemotherapy before surgery is an option if...
- Your tumor is very large relative to the size of your breast
- Your lymph nodes can be felt on physical exam
- The tumor is close to the chest wall or the skin
- You need time to have genetic counseling and testing before you decide what kind of surgery to have
- The surgeon does not think that your cancer can be removed from the breast or lymph nodes without shrinking it first
- You have inflammatory breast cancer (IBC)
Summary
In summary, chemotherapy is given to kill cancer cells that may have spread throughout the body. Chemotherapy can be given before or after surgery.
Decisions about chemotherapy are made with you and your medical team. Many things play a role in whether or not you get chemotherapy.
Chemotherapy is usually given after surgery. For some people, giving chemotherapy before surgery has added benefits.
References
- NCCN Clinical Practice Guidelines in Oncology. Breast Cancer. National Comprehensive Cancer Network. Available at http://www.nccn.org/professionals/physician_gls/pdf/breast.pdf. Version 2.2019-July 2, 2019. Last accessed on: Aug 16, 2020.
- How is Chemotherapy Used to Treat Cancer? American Cancer Society; Nov 22, 2019. Url: https://www.cancer.org/treatment/treatments-and-side-effects/treatment-types/chemotherapy/how-is-chemotherapy-used-to-treat-cancer.html Last accessed on: Aug 16, 2020.