Dr. MJ Bazos MD, Patient Handout

Radiation therapy after Lumpectomy

What is a lumpectomy?

Until a few years ago, women with breast cancer almost always underwent a mastectomy (removal of the whole breast). Lumpectomy (also called “breast-conserving surgery” [BCS] or “partial mastectomy”) is a less radical operation that removes only the diseased part of the breast and leaves healthy breast tissue in place. Studies have now shown that women who have a lumpectomy followed by radiation treatment live just as long as women who choose to have a mastectomy. Four out of 5 women with breast cancer have tumours that are suitable for treatment with lumpectomy.

What is radiation therapy?

Radiation therapy (also called “radiotherapy”) is the use of high-energy x-rays to kill cancer cells.

Do I need radiotherapy if I have a lumpectomy?

Yes, radiotherapy is almost always recommended after lumpectomy. Cancer can return in the same breast after surgery (local recurrence), and it has been proved that radiation reduces this risk significantly. Although there are no guarantees, the benefits of radiotherapy are so great that you should definitely consider it as part of your treatment.

But my doctor says I have a low risk of recurrence because I am

over 50 years old and my tumour was very small.

It is true that your risk of recurrence is relatively low. Still, about 1 in 5 women over 50 years old with small tumours will have a recurrence within 8 years if they have a lumpectomy without radiotherapy afterward. Radiotherapy can reduce that risk to about 1 in 50. It’s an extra margin of safety.

Does radiotherapy have unpleasant side effects?

Radiotherapy can have side effects that occur both during and after the treatment. In the first weeks after beginning radiation therapy, you may notice reddening or swelling of the skin over the breast area and fatigue or tiredness. These problems usually disappear within 3 to 6 months. In the first 5 years after treatment, you may experience discomfort, pain, swelling, discolouration or other skin changes in the breast area. However, over 90% of women are satisfied with the appearance of the breast after lumpectomy and radiation treatment. Some breast tissue may also shrink or become hard due to the death of fat cells, especially in areas where high-dose “boost” treatments were given. This hardening does not mean that the cancer has come back. With current techniques, severe longterm side effects are rare. Even in older studies, which used different techniques and higher doses of radiation than would be recommended today, these problems

occurred in under 2% of patients treated.

Isn’t it true that radiation can cause cancer?

Any danger from radiation depends on the type of radiation, how much is given and how it is applied. There is no convincing evidence that the kind of radiation therapy given after lumpectomy can cause cancer, either in the breast or elsewhere in the body.

I had tissue removed from one small area, but my doctor wants

to radiate the whole breast.

There is good evidence that radiation given to the whole breast is more effective than partial irradiation in preventing a recurrence.

What is a “boost”?

Sometimes, as part of radiotherapy, an extra dose (boost) of radiation is given to the small area where the cancer was removed. Most often it is used when not all of the cancer was taken out during

lumpectomy. Normally, a second operation to remove any remaining cancer is the best choice when this happens. But if this is not possible for some reason, or if you decide not to have more surgery, a “boost” of radiation to the area can be the “second-best” option. However, there is no clear proof that a “boost” of radiation provides any benefit. Research is under way to investigate this question.

What is the best way to give radiation therapy? Is there a

“right” dose of radiation?

Radiation treatment is not given all at once. It is divided into “fractions” — small doses scheduled 5 days a week that are given over 3 to 6 weeks. If “boosts” are given, they are also divided into fractions. So far, no clinical trials have been completed to show exactly which treatment schedule or dose is best. Evidence from existing studies suggests that there are several different schedules that produce similar benefits. Because all of these are acceptable, it may be possible to choose the treatment program that best fits your personal schedule. However, it is important to stay within a standard range. Unusually high doses can result in more severe side effects without giving extra benefit.

Should radiation treatment begin right after surgery? How long a delay is safe?

If you are not having chemotherapy, radiation treatment should begin as soon as possible after your incision heals, usually within 8 weeks after surgery. It is generally believed that radiation treatment should not be delayed longer than 12 weeks after surgery, although there is no proof to support this. If you are having chemotherapy, most cancer centres recommend that radiation treatment be delayed until chemotherapy is finished. Sometimes both kinds of treatment are given together. However, there is no evidence that this improves the outcome, and it can increase the risk of unwanted side effects, especially if any of the anthracycline drugs (drugs like Adriamycin) are used as part of your chemotherapy.

Are there any situations where radiotherapy should not be given after surgery?

Yes. Pregnant women and those who have had previous high-dose radiotherapy to the chest (including radiation for Hodgkin’s disease) definitely should not receive radiation therapy. Radiotherapy may pose an increased risk for some people with severe heart or lung disease. Also, people with scleroderma or systemic lupus erythematosus may be at increased risk for severe side effects from radiotherapy. Some people with certain conditions such as arthritis may be unable to lie flat or to stretch out the arm on the same side as the breast being treated. In these instances it may be difficult or impossible to give radiation treatments properly.