Check Up: Breath-holding cuts incidental radiation
Radiation is a powerful cancer treatment, but protecting healthy tissue from the scatter of damaging rays is challenging. As a result, women who get radiation for cancer in their left breast - which overlaps the heart - have been found to be at increased risk of heart disease and lung cancer.
Radiation is a powerful cancer treatment, but protecting healthy tissue from the scatter of damaging rays is challenging.
As a result, women who get radiation for cancer in their left breast - which overlaps the heart - have been found to be at increased risk of heart disease and lung cancer.
A new study by Thomas Jefferson University researchers confirms that such women can significantly reduce the incidental radiation dose to their hearts with a simple technique: holding their breath.
Intermittent breath-holding enables doctors to monitor the patient and administer a beam of radiation precisely when the distance between the heart and the chest wall is greatest.
That extra space is small, typically only about an inch, but the protective effect is important, said Jefferson radiation oncologist Pramila R. Anne, senior author of the paper in the journal Practical Radiation Oncology.
"What we find is that less than 1 percent of the heart gets a significant dose" of radiation, she said.
That translated to a median reduction in total radiation dose of 62 percent for the 81 left-sided breast cancer patients who completed the study. Equally important, after a median follow-up period of eight years, 96 percent of the women were alive, so their cancer therapy was not compromised by the breath-holding.
The women were not tested to evaluate their cardiovascular health. However, by using mathematical modeling, the researchers concluded that 3.6 percent of the women would have heart disease a decade after radiation therapy - about the same rate as women ages 50 to 79 who do not have radiation therapy.
Breath-holding, also called respiratory gaiting, has been shown to reduce spillover radiation in patients with other types of malignancies, including liver, pancreatic, and lung cancers.
Jefferson was one of the earliest centers to experiment with the technique more than a decade ago, equipping patients with a snorkel-like device called the Active Breathing Coordinator, Anne said.
The device - now made by Elekta, a Swedish company - keeps the patient from inhaling more air while holding the breath, and is connected to a computer that monitors respiration.
In the breast cancer study, patients practiced with the device for about 30 minutes to see whether they could reliably stop breathing for 15 to 20 seconds at a time. During radiation therapy, given for a few minutes per day for three weeks, the patient may have to hold her breath eight times - a task that proved too difficult for five women.
"You have to be a regular breather," Anne said. "Patients with a cough or postnasal drip may have trouble."
The only possible downside to the technique is that it adds slightly to staff training time and workload.
"When all the facts are considered, the marked reduction in cardiac [radiation] dose justifies the utilization of clinic time and resources in department," the researchers wrote.