Breast Cancer: Radiation Therapy

Pictured: Beryl McCormick & Simon Powell Beryl McCormick leads efforts to improve radiation therapy for breast cancer.

Radiation therapy uses high-energy x-rays to destroy cancer cells. At Memorial Sloan Kettering, we use radiation therapy in many different situations for women with breast cancer.

We can use radiation to target the entire breast that contains cancer, for example. Or we can deliver radiation to just the part of the breast affected by cancer.

Following a lumpectomy, we can focus radiation on the breast and, in some cases, the surrounding lymph node area to destroy any stray cancer cells. This approach lessens the chance that cancer will come back.

Partial Breast Radiation

If you’re an older woman with very early-stage breast cancer, we may offer you an intraoperative radiation approach (performed during surgery) in which we deliver radiation to part of the affected breast. When doing a lumpectomy, we apply radiation directly to the area of the breast where a tumor was removed. On average, this approach adds only 30 minutes to the time spent in the operating room — but eliminates the need for radiation after the operation.

Sometimes we give radiation therapy after a mastectomy, but only if there’s a high risk of cancer coming back in that area. Our plastic surgeons and medical oncologists work together to offer an integrated program of postmastectomy radiation to women who’ve undergone immediate reconstruction and require radiation treatment. 

Our approach has resulted in both excellent control of the cancer in the area treated (local control) and a low rate of major radiation-related problems with reconstruction. Women who need systemic therapy, such as chemotherapy, may receive radiation after chemotherapy is completed.

Your treatment team will work with you to identify the best sequence of radiation treatments. A course of standard radiation therapy for breast cancer typically includes five days of treatment a week for four to six weeks. 

Types of Radiation Used for Breast Cancer

We offer several types of radiation therapy for breast cancer. 

Intensity-Modulated Radiation Therapy (IMRT)

In IMRT, a special computer program is used to deliver a consistent dose of radiation to the breast. This technology prevents so-called hot spots (areas that receive more radiation than others due to the shape of the breast) and minimizes acute (immediate) and late (delayed) reactions. In special situations, IMRT is also used to limit the radiation dose to organs close to the breast or lymph nodes being treated.

Radiation Delivered in the Prone Position

In this method, women lie on their stomachs (instead of their backs) and radiation is directed to the affected breast as it hangs through an opening in the table. This approach reduces radiation exposure to nearby vital organs, such as the heart and lungs. It’s been found to be especially useful for women with large breasts.

Image-Guided Radiation Therapy (IGRT)

In IGRT, doctors and radiation therapists use imaging technologies to locate the tumor just before the radiation dose is given while the patient is in the treatment position. This results in a more accurate delivery of radiation directly to the tumor.

Proton Therapy

For some women, our radiation oncologists can use an advanced form of radiation therapy called proton therapy. It delivers high doses of radiation to tumors that may be resistant to conventional forms. Proton therapy directs its cancer-fighting energy to precise locations within the body, allowing our doctors to deliver the necessary dose to the tumor — maximizing the chance of destroying it — while simultaneously lowering the dose to normal tissue and thereby reducing the risk of treatment-related side effects. Currently, this cutting-edge technology is available at only 14 locations in the United States.

Radiation treatments today are very precise, resulting in little harm to surrounding skin or healthy tissues. It’s generally very well tolerated, but after approximately three weeks, there may be some side effects, such as a sunburn-like condition on the skin, fatigue, discoloration of the skin, or swelling and heaviness in the breast.

Your radiation oncologist will explain in detail what to expect and when side effects are likely to appear. He or she can also prescribe a topical skin cream to minimize the side effects.