Cardiac Dose Reduction with Deep-Inspiratory Breath Hold Technique of Radiotherapy for Left-Sided Breast Cancer

Lalitha Kameshwari Sripathi; Parveen Ahlawat; David K Simson; Chira Ranjan Khadanga; Lakshmipathi Kamarsu; Shital Kumar Surana; Kavi Arasu; Harpreet Singh

doi:10.4103/jmp.JMP_139_16

Cardiac Dose Reduction with Deep-Inspiratory Breath Hold Technique of Radiotherapy for Left-Sided Breast Cancer

J Med Phys. 2017 Jul-Sep;42(3):123-127. doi: 10.4103/jmp.JMP_139_16.

Authors

Lalitha Kameshwari Sripathi¹, Parveen Ahlawat¹, David K Simson¹, Chira Ranjan Khadanga², Lakshmipathi Kamarsu¹, Shital Kumar Surana², Kavi Arasu², Harpreet Singh¹

Affiliations

¹ Department of Radiation Oncology, Action Cancer Hospital, New Delhi, India.
² Department of Radiation Oncology, Krishna Institute of Medical Sciences, Hyderabad, Telangana, India.

Abstract

Introduction: Different techniques of radiation therapy have been studied to reduce the cardiac dose in left breast cancer.

Aim: In this prospective dosimetric study, the doses to heart as well as other organs at risk (OAR) were compared between free-breathing (FB) and deep inspiratory breath hold (DIBH) techniques in intensity modulated radiotherapy (IMRT) and opposed-tangent three-dimensional radiotherapy (3DCRT) plans.

Materials and methods: Fifteen patients with left-sided breast cancer underwent computed tomography simulation and images were obtained in both FB and DIBH. Radiotherapy plans were generated with 3DCRT and IMRT techniques in FB and DIBH images in each patient. Target coverage, conformity index, homogeneity index, and mean dose to heart (Heart D_mean), left lung, left anterior descending artery (LAD) and right breast were compared between the four plans using the Wilcoxon signed rank test.

Results: Target coverage was adequate with both 3DCRT and IMRT plans, but IMRT plans showed better conformity and homogeneity. A statistically significant dose reduction of all OARs was found with DIBH. 3DCRT_DIBH decreased the Heart D_mean by 53.5% (7.1 vs. 3.3 Gy) and mean dose to LAD by 28% compared to 3DCRT_FB. IMRT further lowered mean LAD dose by 18%. Heart D_mean was lower with 3DCRT_DIBH over IMRT_DIBH (3.3 vs. 10.2 Gy). Mean dose to the contralateral breast was also lower with 3DCRT over IMRT (0.32 vs. 3.35 Gy). Mean dose and the V₂₀ of ipsilateral lung were lower with 3DCRT_DIBH over IMRT_DIBH (13.78 vs. 18.9 Gy) and (25.16 vs. 32.95%), respectively.

Conclusions: 3DCRT_DIBH provided excellent dosimetric results in patients with left-sided breast cancer without the need for IMRT.

Keywords: Deep-inspiratory breath hold; intensity modulated radiotherapy; left anterior descending; three-dimensional radiotherapy.