Radiation has been part of breast cancer treatment since early 1900s. It has given many people the chance to survive breast cancer, but some survivors experienced an unwanted side effect years later – heart disease.
The benefits of treating cancer outweigh the costs of slightly increased heart disease risk, but the thought of heart trouble is worrisome.
The good news is modern radiation treatment poses very minimal heart risk for most patients.
People treated decades ago may be at slightly increased risk for heart disease. However, healthy lifestyle changes can minimize that risk.
Greater risk in past decades
“The issue of radiation increasing heart disease risk mainly affects people who were treated in the 1940s through the 1980s,” said Dr. Patricia Lillis, a radiation oncologist at Marshfield Clinic Cancer Center in Stevens Point. “Over time the risk has decreased as doctors became aware of the problem and made changes to treatment techniques.”
In the past, larger fields encompassing the breast, lymph nodes and chest wall were treated, exposing more healthy tissue to radiation. A number of chemotherapy drugs also have side effects on the heart. This led to accelerated heart disease onset for some people.
In a study of women who had radiation between 1958 and 2001, those with low baseline heart disease risk who had right breast radiation had the smallest risk increase for heart disease. Risk increased the most for women with high baseline heart disease risk who had left breast radiation. The overall risk increase for all women treated was still very small. The gains in survival and cure are universally believed to far outweigh that risk.
Significant technological breakthroughs in imaging and treatment delivery took place in the late 1980s and early 1990s. Most practices around the country began updating their equipment and Marshfield Clinic has remained on the cutting edge.
Modern treatments reduce risk
Modern radiation therapy is much less likely to cause heart problems, Lillis said.
Doctors know more about how cancer acts and how radiation affects cancer cells and healthy tissue. They use computers to plan precise dosing and delivery. Better machines target smaller fields encompassing the breast.
Radiation can be delivered at the moment in your breathing cycle when the heart is farthest from the chest wall. This technique is called respiratory gating and it minimizes radiation to healthy tissue.
There is much better understanding of when areas containing lymph nodes don’t need to be treated. In some very early stage cancers, only a portion of the breast needs to be treated. Studies are beginning to show select patients can skip radiation altogether.
“I can’t guarantee the risk of heart problems is zero for everyone, but I want to emphasize how much better modern treatments are,” Lillis said. “Marshfield Clinic is continually updating equipment to be on the cutting edge and uses the most advanced treatment techniques.”
Practice heart healthy habits
If you’re concerned radiation has increased your risk for heart problems, the best thing to do is follow standard advice for reducing heart disease risk, which includes:
- Not smoking.
- Maintaining a healthy weight.
- Controlling high blood pressure, cholesterol and diabetes.
Talk to your primary care doctor or cardiologist about your heart disease risk if you were treated for breast cancer in the past. Talk about how to reduce your existing heart risks if you’re about to undergo breast cancer treatment.