Nationwide Trends in Heart-Sparing Techniques Utilized in Radiation Therapy for Breast Cancer

Abstract

PurposeRadiation dose to the heart correlates with cardiac-related deaths and may partially diminish the benefit of radiation for breast cancer. This study assessed the current nationwide trends in heart-sparing techniques for breast cancer radiation. Methods and MaterialsIn November 2017, an institutional review board–approved survey was sent to radiation oncologists in the United States. Questions assessed demographics and the type and frequency of heart-sparing techniques. Data were analyzed using descriptive statistics and χ2 tests. ResultsIn total, 530 responses (13%) were obtained. Most physicians had practiced >15 years (46%), with most in a private setting (59%). Eighty-three percent of physicians offered prone positioning and/or deep inspiration breath hold (DIBH). This was more common in academic practice (P < .01). Seventy-three percent of physicians used heart-sparing techniques for more than three-fourths of left-sided patients. The most commonly used technique was DIBH, and 43% of physicians used the technique more than three-fourths of the time. Commonly used DIBH systems were Varian RPM (54%) and Vision RT/Align RT (31%). No increase in DIBH use was observed with regional nodal irradiation, and coverage of internal mammary chain nodes varied. Patient tolerance (78%) and cardiac-to-chest wall distance (72%) were the most common determinants of DIBH in left-sided patients. Twenty-three percent of physicians used DIBH for right-sided patients, with lung (64%) and heart sparing (46%) as the most common reasons for use. Lack of facilities was the most common reason not to use DIBH (61%). ConclusionsMost respondents offer heart-sparing techniques for breast cancer radiation; this is more common in academic centers. DIBH is the most common technique across all practice settings. DIBH is much less commonly used in right-sided patients but is still used by >20% of practitioners, with lung and heart sparing cited as reasons for use. More data are needed to determine if and when this technique should be used in right-sided cases.