Radiation for Early-Stage Breast Cancer

Topic Overview

When is radiation used for early-stage breast cancer?

Radiation therapy is given to most women with early-stage breast cancer who choose breast-conserving surgery such as lumpectomy. Their other surgery option is mastectomy, which removes the whole breast. Many women choose breast-conserving surgery plus radiation so they can keep their breast.

Women who have breast-conserving surgery plus radiation have the same survival rates as women who have mastectomy.^{footnote 1}

How is radiation therapy for early-stage breast cancer done?

Breast cancer is usually treated with external beam radiation. For this treatment, the radiation comes from a machine outside the body and is aimed at the cancer. In most cases, the whole breast is treated with radiation. If cancer was found in your lymph nodes, other areas may be treated with radiation too.

Radiation treatments are painless, like getting an X-ray. They are usually given 5 days a week during short appointments at a hospital or clinic.

Most women get radiation treatments for 5 to 7 weeks. But some women may have the option to get slightly higher doses of radiation for about 3 weeks. This is called hypofractionated radiation therapy. Studies have shown that this shorter treatment schedule works as well as the longer schedule to keep cancer from coming back.^{footnote 2}

Your doctor may recommend the 3-week treatment schedule if all of the following are true for you:^{footnote 3}

• You are age 50 or older.
• You had a lumpectomy.
• Your tumor was smaller than 5 cm.
• No cancer was found in your lymph nodes.
• You did not have chemotherapy.

What are the side effects of radiation therapy?

Radiation is very good at killing cancer cells, but it can also affect normal cells. This can lead to side effects. The most common ones are:

• Feeling very tired.
• Skin changes in the area treated with radiation. The skin may be red, dry, and sore.
• Swelling and heaviness in your breast.

Most side effects will go away within a few weeks after you finish your treatments. But it may take longer to get your energy back.

When is radiation not used after lumpectomy?

Some women may not benefit from radiation therapy after lumpectomy. You may not need radiation if all of the following are true for you:^{footnote 4}

• You are age 70 or older.
• Your tumor was small (less than 2 cm).
• No cancer was found in your lymph nodes.
• You are taking hormone therapy, such as tamoxifen, because your tumor contained hormone (estrogen or progesterone) receptors.