Preliminary data on prone positioning during whole-breast radiotherapy following breast-preservation surgery “suggest that radiation exposure to the heart and lung can be reduced compared with supine positioning with similar efficacy,” according to a research letter in the Journal of the American Medical Association. The letter notes that while radiation therapy to the breast contributes to improved outcomes in patients with breast cancer after breast-preservation surgery, whole-breast radiotherapy “is associated with damage to the heart and lung, increased cardiovascular mortality, and lung cancer development, with risks that remain 15 to 20 years after treatment. These consequences occur when breast cancer patients are treated supine.”
The authors of the letter conducted a study to test the hypothesis that prone positioning is superior to standard supine positioning, comparing the volume of heart and lung within the radiation field. The prospective study included patients with breast cancer who underwent two CT simulation scans, the first supine and the next prone. The researchers found that prone positioning was associated with a reduction in the amount of irradiated lung in all 400 patients with breast cancer enrolled in the study and in the amount of heart volume irradiated in 85% of the 200 patients with left breast cancer.
“The study is limited to a single institution. A multi-institutional prospective trial with outcome measures is warranted to confirm these findings,” the investigators advised. “If prone positioning better protects normal tissue adjacent to the breast, the risks of long-term deleterious effects of radiotherapy may be reduced.” ■
1.Formenti SC, DeWyngaert JK, Jozsef G, et al: Prone vs supine positioning for breast cancer radiotherapy. JAMA 308:861-863, 2012.