Radiation therapy uses high-energy radiation such as X-rays to destroy cancer cells. Our radiation oncologists (doctors who specialize in treating cancer with radiation therapy) use the most advanced equipment and techniques. They precisely target radiation beams to tumors, providing powerful treatment while avoiding damage to healthy tissue nearby.
Radiation Therapy: Treatment Goals
Radiation therapy is considered local treatment because it focuses on the tumor in the breast, not on cancer in other parts of the body. The treatment goals of radiation therapy are to:
- Destroy any cancer cells that may remain after breast cancer is surgically removed. Radiation therapy given after surgery or another primary treatment is called adjuvant therapy.
- Lower the risk of cancer coming back (recurring) after surgery, either at the original tumor site (or nearby) or in other parts of the body
- Shrink or slow the growth of cancerous tumors that are inoperable (cannot be removed with surgery)
Types of radiation therapy
At the Stanford Breast Cancer Program, we use external radiation, also known as external beam radiation therapy (EBRT), for the treatment of breast cancer.
External beam radiation therapy
Our radiation oncologists deliver this type of radiation to the breast, or area where the breast was, using linear accelerator machines. There are many ways that external radiation can be used to treat your breast cancer:
- Whole-breast, or chest-wall, radiation: Radiation to the whole breast, or chest wall (area where the breast was prior to removal), to lower the chance of cancer returning in that area. We use whole-breast radiation after a lumpectomy to destroy any potential remaining cells in the breast, or chest wall radiation after mastectomy to destroy any potential remaining cells in the chest wall. This type of radiation is traditionally given once a day, 5 days a week, for 5 to 6 weeks (standard course). We also sometimes deliver this therapy in larger doses each day over a shorter total time – only 3 to 4 weeks (short course). If your breast cancer is on the left, we use a technique called inspiratory-breath hold for your treatments:
- Inspiratory breath hold: A technique where you are asked to take a breath in and hold during treatment. By taking a deep breath in, you are moving your breast or chest wall away from your heart. This helps minimize the amount of radiation that goes to your heart, reducing the risk of long term side effects.
- Partial-breast irradiation: This type of radiation focuses on just part of the breast around where the tumor was. At Stanford, we deliver partial-breast irradiation using an external radiation technique called 3-dimensional conformal radiotherapy accelerated partial breast irradiation (3D-CRTAPBI),, which uses 3-D imaging to shape radiation beams to the exact shape of the tumor cavity, and delivers radiation twice a day over 5 days (one week) total.
- Intraoperative radiation therapy (IORT): Your radiation oncologist coordinates with your surgeon to deliver treatment during your surgery. Once your surgeon removes the breast tumor, your radiation oncologist delivers focused radiation to the tumor site, before the incision is closed. IORT is given just once, in a single dose.
Your doctor will discuss which type of radiation treatment is best for you, which is based on many factors including your age, type of breast cancer, and stage.
Radiation therapy in combination with other treatments
Many people need both radiation therapy and surgery or systemic therapy during breast cancer treatment. The factors that influence our recommendation include:
- Type and stage of cancer
- Presence of genetic mutations such as BRCA1 or BRCA2
- Your age, overall health, and personal preferences
Your doctor will discuss the options appropriate for your care, based on your specific case. In general, we recommend radiation therapy in these situations:
During or after lumpectomy
For people with either invasive or noninvasive breast cancer, radiation therapy after lumpectomy is considered standard treatment.
A lumpectomy (also called breast-conserving surgery or partial mastectomy) removes only part of the breast and may not get rid of all cancer cells. Radiation therapy such as IORT (during surgery) or partial- or whole-breast radiation (after surgery) can help lower the chance of cancer returning to that breast.
Many people will not need radiation after a mastectomy. We may recommend radiation therapy if the:
- Tumor that the surgeon removed was 5 cm or larger
- Cancer has spread to nearby lymph nodes, the chest wall, or the overlying skin on the breast
- Margin (edges of tissue around a tumor) tests positive for cancer cells
If you need radiation after mastectomy, this can be done with or without reconstructive surgery.
For metastasized breast cancer
Breast cancer can spread (metastasize) to other parts of the body, such as the bones, brain, or lungs. If so, we may use radiation therapy to treat the cancer wherever it develops in the body.