A technique called “deep inspiration breath hold” during radiation shows promise as a way to minimize the impact treatments can have on the heart, especially on patients with cancer in the left breast. Ryan Nowak, M.D., a radiation oncologist at Sanford Health, explains how it works and its benefits.
Historically, the radiation beam went across the chest wall to include much of the breast. Patients would breathe freely, so their chest would rise and fall normally, and the radiation would skim across the chest wall.
Because of the heart’s location, that meant it was situated right in the treatment field, so the entire heart, or at least a good portion of it, was treated. There weren’t many ways to treat the target on the breast without often treating the heart with a significant dose of radiation.
A study published in 2013 in the New England Journal of Medicine looked at thousands of cancer patients and determined how many developed cardiovascular problems compared to people who never received radiation.
It concluded that radiation treatment to the left breast increased the chances of the patient eventually developing heart disease or dying from some type of cardiac problem.
The risk can last 20 years or more, so the younger a patient is, the more time there is to develop problems down the line.
Although the decrease in mean heart dose with the deep inspiration breath hold technique is modest for each individual patient, the large number of patients treated with left-sided breast cancer will eventually translate into a meaningful decrease in cardiac-related complications among the population.
There were 230,000 cases of breast cancer last year, so a lot of patients are getting radiation, which means that even a small percentage increase in all those people translates to a measurable improvement.
Not everyone’s a good candidate for the deep inspiration breath technique, but most people are. Sometimes it doesn’t work on smokers or if the person can’t hold their breath or do it consistently.
The technique has evolved, and the current way of doing it is the most advanced and accurate way to decrease the dose of radiation to the left heart and lung.
It basically entails holding your breath of 20 seconds. When you take a deep breath, the breast actually moves out away from the heart.
During the treatment, a camera monitors the position of the patient’s chest and breast wall. When she takes a breath that’s too big or too small than what the machine is expecting, it won’t turn on.
If a patient is a candidate, they receive a pamphlet that explains how to practice at home for a few days by taking a breath and holding it consistently.
Though most deep inspirational breathing is done on women with cancer in the left breast, it holds promise for some other radiation treatments, including those for Hodgkin lymphoma, lung cancer and perhaps cancer of the pancreas.
Anything that can move during treatment, you can imagine a benefit there. If it’s not going to move, the treatment field can shrink so it focuses the radiation.