Grace Lee1, Tara Rosewall2, Anthony Fyles2, Nicole Harnett2, Robert E Dinniwell3. 1. Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Canada. 2. Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Canada; Department of Radiation Oncology, University of Toronto, Canada. 3. Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Canada; Department of Radiation Oncology, University of Toronto, Canada. Electronic address: rob.dinniwell@rmp.uhn.on.ca.
Abstract
BACKGROUND AND PURPOSE: Left-sided breast radiotherapy (RT) can result in cardiac exposure. This study aims to identify predictive anatomic features in women requiring breath-hold (RT(BH)) for cardiac sparing during adjuvant whole breast RT. MATERIAL AND METHODS: We retrospectively reviewed free-breathing (FB) CT scans of 80 women previously treated with left-sided breast RT. Unfavourable cardiac anatomy was defined as the number of consecutive axial CT slices (2 mm) in which the anterior chest wall contacted the heart (Contact(Heart)) or left ventricle (Contact(LV)). The sternal angle and Haller Index (HI) were used to measure chest concavity. Position and volume of post-operative cavity was also quantified. RESULTS: Heart mean dose (D(mean)) was strongly correlated with Contact(LV) (r=0.625, p<0.001) and Contact(Heart) (r=0.524, p<0.001) but not significantly correlated with tumor size, cavity volume, heart volume, cavity distance to chest wall, sternal angle, or HI. ROC analysis of Contact(Heart) was most predictive of the need for breath-hold (RT(BH)) technique [Area Under Curve=0.815 (SE: 0.048; 95% CI: 0.721-0.91)] and ⩾25 Contact(Heart) CT slices predicted for heart D(mean) ⩾1.7 Gy (68% sensitivity and 82% specificity). CONCLUSION: Contact(Heart) on FB CT of ⩾25 axial slices (2 mm), ⩾50 mm of para-sagittal heart contact, was predictive of higher heart D(mean) and suggest a potential need for RT(BH).
BACKGROUND AND PURPOSE: Left-sided breast radiotherapy (RT) can result in cardiac exposure. This study aims to identify predictive anatomic features in women requiring breath-hold (RT(BH)) for cardiac sparing during adjuvant whole breast RT. MATERIAL AND METHODS: We retrospectively reviewed free-breathing (FB) CT scans of 80 women previously treated with left-sided breast RT. Unfavourable cardiac anatomy was defined as the number of consecutive axial CT slices (2 mm) in which the anterior chest wall contacted the heart (Contact(Heart)) or left ventricle (Contact(LV)). The sternal angle and Haller Index (HI) were used to measure chest concavity. Position and volume of post-operative cavity was also quantified. RESULTS: Heart mean dose (D(mean)) was strongly correlated with Contact(LV) (r=0.625, p<0.001) and Contact(Heart) (r=0.524, p<0.001) but not significantly correlated with tumor size, cavity volume, heart volume, cavity distance to chest wall, sternal angle, or HI. ROC analysis of Contact(Heart) was most predictive of the need for breath-hold (RT(BH)) technique [Area Under Curve=0.815 (SE: 0.048; 95% CI: 0.721-0.91)] and ⩾25 Contact(Heart) CT slices predicted for heart D(mean) ⩾1.7 Gy (68% sensitivity and 82% specificity). CONCLUSION: Contact(Heart) on FB CT of ⩾25 axial slices (2 mm), ⩾50 mm of para-sagittal heart contact, was predictive of higher heart D(mean) and suggest a potential need for RT(BH).
Authors: Lucas C Mendez; Alexander V Louie; Carolina Moreno; Matt Wronski; Andrew Warner; Eric Leung; Roberto Sakuraba; Juliana K Helito; Ana Rezende; Icaro T Carvalho; Eduardo Weltman Journal: Radiat Oncol Date: 2018-07-04 Impact factor: 3.481
Authors: Sofian Benkhaled; Carolina Gomes da Silveira Cauduro; Nicolas Jullian; Antoine Desmet; Diana Rodriguez; Younes Jourani; Dirk Van Gestel; Alex De Caluwé Journal: Front Oncol Date: 2022-08-18 Impact factor: 5.738