ESTRO 2025 - Abstract Book

S457

Clinical - Breast

ESTRO 2025

Results:

Mean cardiac dose of the overall sample was 3.68 ± 1.65 Gy with a maximum dose of 34.3 ± 6.85 Gy. Compared to non-coached participants, coached participants had lower mean (3.65 vs 3.72 Gy) and maximum (33.7 vs 34.8 Gy) cardiac doses, but were not statistically significant. Median V5, V10, and V30 of percentage cardiac volume exposures of overall sample was 12.2 [13.3], 4.95 [4.48], and 0.015[0.75], respectively. No significant differences were noted when comparing percentage cardiac volume exposure and V20 of the percentage lung volume exposure between the coached and non-coached groups. Coached patients were, found to have a significantly lower mean V17 (18.3 [5.69] vs 21.6 [5.93]; p < 0.05 ) when comparing percentage lung volume exposures. Conclusion: In conclusion, while no significant differences were observed in cardiac doses, coaching significantly reduced the mean V17 lung dose. These findings suggest that structured coaching in the DIBH technique can reduce lung exposure and minimize cardiac toxicity. Implementing coaching for all compliant left-sided breast cancer patients may improve treatment outcomes and safety.

Keywords: Patient Coaching, DIBH, Left breast cancer

References: 1.Cuzick J, Stewart H, Rutqvist L et al. Cause specific mortality in long term survivors of breast cancer who participated in trials of radiotherapy. J Clin Oncol. 1994 Mar;12(3):447-53 2.Yeboa DN,Evan SB. Contemporary breast radiotherapy and cardiac toxicity. In: Seminars in Radiation Oncology. 2016 Jan; 26(1):71-8. WB Saunders.