For women diagnosed with early-stage breast cancer, lumpectomy followed by radiation therapy has been shown to be as effective as mastectomy without radiation for removing the cancer AND minimizing the risk of the cancer coming back (recurrence). Radiation therapy after lumpectomy can destroy any cancer cells that may have been left behind after surgery, making recurrence less likely.
Still, studies have found a link between radiation therapy for breast cancer and a higher risk of heart and lung problems, especially if the cancer is in the left breast, the same side as the heart.
Now a new study with more than two decades of follow-up suggests that women who have lumpectomy and radiation therapy don’t have a higher risk of heart problems than women who have mastectomy.
The study was presented at the American Society for Radiation Oncology 2012 Annual Meeting.
Nearly 250 women diagnosed with early-stage breast cancer from 1979 to 1987 had been randomly assigned to have lumpectomy followed by radiation therapy or mastectomy as part of a National Cancer Institute study. Women who had cancer in the lymph nodes also received a chemotherapy regimen of Doxil (chemical name: doxorubicin) and Cytoxan (chemical name: cyclophosphamide).
After 25.7 years, 102 of the women were alive and 50 of them agreed to have tests to study their heart function:
- 26 of the women had lumpectomy plus radiation therapy
- 24 women had mastectomy
The women had the following tests:
- physical exam
- cardiac laboratory tests
- cardiac MRI
- CT angiography (a CT scan of the body’s large blood vessels) to check for disease and calcium build-up in the heart arteries
Three of the women who had lumpectomy and four of the women who had mastectomy already had either bypass surgery or angioplasty surgery to open blocked arteries in their hearts.
The results of the heart function tests were very similar for the two groups of women. They had similar:
- 10-year risk of heart attack (5.1% for women who had lumpectomy and 5.7 for women who had mastectomy)
- ventricular mass
- heart volume and function
- heart artery calcium build-up
In both groups, women who had chemotherapy had more atherosclerosis (hardening of the arteries).
In women who had lumpectomy followed by radiation therapy, heart structure and function were the same for women who had cancer in the left breast compared to women who had cancer in the right breast.
While the results of this study are reassuring, it’s important to know that only about 20% of the women who were originally enrolled in the study were available for the heart tests. Many women who died could have died of heart disease, which would make the results less reassuring.
Advances in radiation therapy have greatly reduced the amount of radiation exposure to the heart, lungs, and other healthy tissue. Doctors use computers to plan radiation therapy that is extremely precise in dose and delivery. Some radiation therapy equipment (called respiratory gating) tracks heart beats and lung movement and effectively blocks those tissues from radiation exposure. Other tools, such as intensity modulated radiation therapy, allow the oncologist to change the intensity of the radiation during treatment to avoid healthy tissue.
If you’ve been diagnosed with early-stage breast cancer, you and your doctor will consider the characteristics of the cancer, your unique situation, your surgical options, and your treatment options after surgery when creating your treatment plan. If you choose lumpectomy, it’s very likely that radiation will be recommended after surgery. Talk to your radiation therapy treatment team about how they’ll make sure that you get only the radiation therapy required to effectively treat the cancer. Together, you can plan your treatment to minimize any risks.
You can learn more about radiation after breast cancer surgery in the Breastcancer.org Radiation Therapy section.