Radiotherapy for left-sided breast cancer can result in significant dose to cardiac structures (heart and left anterior descending artery (LAD)). Current literature suggests that there is a progressive relationship between the radiation dose and the risk of cardiac toxicities [1-4]. The DIBH technique has been used to minimize the dose to the heart and the LAD during radiotherapy for cancer of the left breast [5-6]. DIBH requires the patient to hold their breath whilst the radiotherapy treatment is delivered and this can be accomplished through...

The vDIBH technique employed at Chris O’Brien Lifehouse does not use commercially available devices for treatment delivery. We employ a vDIBH technique described by Jensen et al [9] wherein the patient’s breath-hold is assessed for adequacy whilst a marker is placed at the level of the patient’s lateral tattoo. The level of the marker is measured from both FB and vDIBH computed tomography (CT) scans and this measurement is recorded for treatment. The FB Planning CT-scan is analysed to see if the patient would benefit...

Planning measurements (Table 1) Compared with FB, vDIBH results in statistically significant reduction in heart mean dose (1.63Gray (Gy) vs. 3.62Gy, p = 0.0000002), maximum dose (33.61Gy vs. 45.76Gy, p = 0.0004), V30 (0.24% vs. 3.67%, p = 0.000002), V20 (0.46% vs. 4.88%, p = 0.0000005), and heart volume (490.55cc vs. 546.81cc, p = 0.0004). These results are reflected in the LAD mean dose (5.92Gy vs. 20.63Gy, p = 0.000001), maximum dose (22.46Gy vs. 41.54Gy, p = 0.0000001) and V30 (1.66% vs. 38.16%, p =...

Treatment setup errors were consistent with other studies of vDIBH which have used EPI for verification [6, 10], suggesting that vDIBH treatment setup is at least as reproducible as standard free-breathing breast radiotherapy. Overall the results of these measurements indicate that vDIBH is an effective, reproducible, and safe technique to reduce the dose to cardiac structures. Further research is required to determine the accuracy and reproducibility of using this vDIBH technique with cine imaging to assess the real-time reproducibility of this technique.

1. Early Breast Cancer Trialists’ Collaborative Group (EBCTCG). Effects of radiotherapy and of difference in the extent of surgery for early breast cancer on local recurrence and 15-year survival: an overview of randomised trials. The Lancet. 2005; 366; 2087-106. 2. Darby SC, McGale P, Taylor CW, Peto R. Long-term mortality from heart disease and lung cancer after radiotherapy for early breast cancer: prospective cohort study of about 300,000 women in US SEER cancer registries. Lancet Oncology. 2005; 6; 557-65. 3. Correa CR, Litt HI, Hwang,...