Dose-sparing effect of deep inspiration breath hold technique on coronary artery and left ventricle segments in treatment of breast cancer. (January 2021)

• Record Type: Journal Article
• Authors: Song, Jiheon; Tang, Terence; Caudrelier, Jean-Michel; Bélec, Jason; Chan, Jessica; Lacasse, Patricia; Aldosary, Ghada; Nair, Vimoj
• Is Part Of: Radiotherapy and oncology. Volume 154(2021)
• Page Start: 101
• Page End: 109
• Publication Date: 2021-01
• Subjects: Breast cancer -- Left anterior descending coronary artery -- Deep inspiration breath hold -- Radiotherapy; Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2020.09.019
• Languages: English
• ISSNs: 0167-8140

Abstract

Highlights: DIBH reduces radiation dose to the heart, left ventricle, coronary arteries and left lung. Greatest dose reductions from DIBH were to the distal LAD (−14.4 Gy) and apical left ventricle (−12.1 Gy) segments. Reducing dose to these cardiac structures may improve radiation-induced cardiac toxicity. Abstract: Background and purpose: The risk of radiation-induced cardiac injury remains a challenging problem in the treatment of breast cancer. Certain cardiac structures receive higher doses than others, which results in variable frequencies of radiation-induced injuries across these structures. Radiation dose can be reduced using the deep inspiration breath hold (DIBH) technique. We aimed to investigate the dose reductions from DIBH in individual cardiac segments. Materials and methods: A dosimetric analysis was performed on left-sided breast cancer patients who underwent breast-conserving surgery and whole breast irradiation. Radiation doses to the cardiac structures were compared between the DIBH and free-breathing (FB) techniques and the dose reductions with DIBH were correlated to the lung expansion. Results: For the 75 patients included in our study, DIBH effectively reduced doses to the heart, left lung, left anterior descending coronary artery (LAD) and left ventricle (LV), but the degree of dose reductions was variable across different structures. The absolute dose reductions were greatest in the distal LAD (14.4 Gy) and apical LV (12.1 Gy) segments, compared with the other LAD (middle 9.7 Gy, proximal 1.6 Gy) and LV (anterior 5.3 Gy, lateral 2.9 Gy, septal 2.0 Gy, inferior 0.2 Gy) segments. Left lung expansion was significantly correlated with the dose reductions in the LAD (Spearman's rank correlation coefficient, ρ, 0.304) and LV ( ρ, 0.420) segments. Conclusions: Our study demonstrates the dose-sparing effects of DIBH in various cardiac structures, especially the distal LAD and apical LV segments. The large dose reductions seen in the distal LAD and apical LV segments could potentially translate into clinical benefit of reduced cardiac toxicity, as these structures have been previously shown to receive the highest doses and are associated with radiation-induced injury.