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Facts About Breast Cancer

Breast cancer is the most common type of cancer in American women, according to the American Cancer Society. This year, 268,600 women and 2,670 men will learn they have breast cancer. Another 62,930 women will learn they have noninvasive (also called in situ) breast cancer. Breast cancer can often be cured.

Radiation Therapy for Breast Cancer


If you find out you have breast cancer, you should discuss your treatment options with your physician. Breast cancer treatment will vary depending on the stage and location of the cancer.

Breast cancer treatment options include:

Radiation Therapy after surgery can decrease the chance of cancer returning in the breast and improve survival. Radiation therapy involves delivering focused radiation to the breast or chest wall, and sometimes the lymph nodes, to treat cancer cells not detected or removed by surgery. Radiation therapy kills cancer cells by destroying their ability to multiply.

Medical Therapy is often recommended to improve cure rates or prevent a new breast cancer from developing. A medical oncologist will evaluate you and determine what medications may be most helpful in accomplishing those goals.

Chemotherapy has the ability to destroy cancer cells. Often, two or three different types of drugs may be combined to get the best outcome. While the dose and schedule for treatment varies, chemotherapy is usually delivered every two to three weeks over a period of a few months.

Hormonal Therapy can block the effects of the female hormone, estrogen, in the body. Estrogen has been shown in some cases to cause your tumor to grow. Usually taken as a daily pill, hormonal therapy may be started during or after radiation therapy is completed.

Surgery is often followed by radiation therapy to decrease the risk of cancer returning in the breast, chest wall and/or lymph nodes.

Lumpectomy, or partial mastectomy, is the surgical removal of the cancerous tissue along with a small rim of surrounding healthy breast tissue. This type of breast-conserving surgery is often followed by radiation therapy.

Mastectomy is the surgical removal of the entire breast. Sometimes, breast reconstruction can be performed after the mastectomy. Radiation is sometimes recommended after mastectomy as well.

Both mastectomy and breast-conserving therapy (surgery and radiation) can be equally effective approaches in curing breast cancer. Ask your radiation oncologist about the risks and benefits of both options.


After lumpectomy, the usual course of radiation treats the whole breast and, if needed, nearby lymph node areas. The radiation beam comes from a linear accelerator, or linac. The radiation beam is a specialized X-ray, and is painless. Each treatment is brief. Treatment is delivered every day, five days a week, Monday through Friday. The full course of treatment is usually delivered over three to seven weeks, depending on findings during surgery.

Before beginning treatment, you will be scheduled for a planning session to map out the area to treat. This procedure is called a simulation. Simulation involves having X-rays and/or a CT scan. Tiny tattoo-like marks made on your skin help the radiation therapist precisely position you for daily treatment. Typically, radiation therapy is done with high energy X-rays, or photons. If needed, electrons may be used to treat the area where the lump was removed with a less penetrating, more focused beam.

Recent clinical trials suggest that whole breast radiation may be shortened by treating the tumor with higher daily doses over less time.

Additional research suggests women aged 70 or older with hormone receptor positive early-stage breast cancer benefit from radiation in terms of lowering their risk of getting cancer again in the treated breast but has not been shown to affect long-term survival. Discuss with your radiation oncologist whether treatment with radiation is necessary.


Ongoing research suggests that it may be safe to give radiation treatment to only the part of the breast that had the tumor, over a shorter period of time.

There are two approaches to APBI:

  1. Breast brachytherapy involves placing flexible plastic tubes called catheters, or a balloon, directly into the cavity where the tumor was removed. A small, radioactive seed is guided into the catheters or balloon and is left in place for several minutes based on the treatment plan designed by your radiation oncologist. The procedure is repeated twice daily for a period of five days, then the catheters or balloon are removed and the treatment is finished.
  2. External beam radiation with 3-D CRT is delivered in a similar way to standard whole breast radiation using a linear accelerator. However, it is more focused on the area around the surgery. Treatment occurs twice daily over a one-week period.

The long-term results of these techniques appear promising but are still being studied. Talk with your radiation oncologist for more information.


After a mastectomy, your doctor may suggest radiation therapy for the chest wall and nearby lymph node areas. Whether or not radiation therapy should be used after removal of your breast depends on several factors such as the number of lymph nodes involved, tumor size and whether or not cancer cells were found near the edge of the surgical site. Women planning to undergo reconstruction should discuss the impact of post-mastectomy radiation with their radiation oncologist.


It is important to care for yourself as well as possible during radiation therapy.

  • A balanced diet, a mild amount of physical activity, and taking time to rest are all important parts of your cancer treatment.
  • Nutrition is important. Eat a balanced diet. Let your doctor know if you have trouble swallowing, food tastes funny or you have trouble eating.
  • Follow your doctor’s orders, and if you are unsure of anything, ask your nurse or doctor any question you may have about your treatment.
  • Be sure to tell your radiation oncologist about any vitamins or dietary supplements that you are currently taking to make sure they are safe to take during radiation therapy.
  • Treat the skin exposed to radiation with special care. Stay out of the sun, avoid hot or cold packs, and only use lotions and ointments after checking with your nurse or doctor.
  • You should also be sure to clean the skin over the areas receiving radiation therapy with warm water and mild soap.

Completing treatment and recovery can be challenging. Seek out help from support groups and friends ahead of time. If you have a support network in place before and during treatment, it will be easier to get through side effects since people you can count on will be around to help you. If you need additional support, let your doctor and nurse know.


Side effects are usually temporary and typically go away shortly after treatment ends. Below is a list of possible side effects you might notice during your treatment.

  • Skin irritation similar to a sunburn, sometimes with a peeling reaction toward the end of treatment.
  • Breast swelling can be mild to moderate.
  • Mild tenderness in the breast or chest wall. This will slowly get better over time.
  • Mild fatigue that generally gets better a month or two after treatment ends.

Many of these side effects can be controlled with medications. Tell your nurse or doctor if you experience any discomfort so they can help you feel better.

After the short-term side effects of radiation therapy resolve, others may become noticeable months or years later.

  • Breast firmness or mild shrinkage.
  • Change in skin color and thickness. Sometimes new blood vessels will appear.
  • Scarring of a small part of the lung just under the breast. Generally, no side effects are noticed but rarely radiation may cause a dry cough or shortness of breath that is treatable.
  • Mild decreased range of motion and/or shoulder discomfort.
  • Hand or arm swelling, called lymphedema, can occur but depends upon the extent of surgery and radiation.

Many factors affect your risk for these side effects. Please talk to your radiation oncologist to learn more about how likely these side effects may be for you.

© American Society for Radiation Oncology, 2019.