ESTRO meets Asia 2024 - Abstract Book

S79

Interdisciplinary – Breast

ESTRO meets Asia

21. Razvi Y, McKenzie E, Wronski M, Zhang L, Vesprini D, Bosnic S, et al. Factors affecting mean heart dose in patients receiving breast radiotherapy from 2011 to 2018 in a single institution. Journal of Medical Imaging and Radiation Sciences. 2020 Sept;51(3):379–93. doi:10.1016/j.jmir.2020.03.003 22. Van Parijs H, Reynders T, Heuninckx K, Verellen D, Storme G, De Ridder M. Breast conserving treatment for breast cancer: Dosimetric comparison of different non-invasive techniques for additional boost delivery. Radiation Oncology. 2014 Jan 27;9(1). doi:10.1186/1748-717x-9-36

23. Saadeldin AM, Elwan AM. Characterization of irregular electron beam for boost dose after whole breast irradiation. Reports of Practical Oncology & Radiotherapy. 2020 Mar;25(2):168–73. doi:10.1016/j.rpor.2020.01.007

153

Proffered Paper

Effect of 3DCRT/IMRT/Tomotherapy on left anterior descending artery dose in left breast cancer.

Sweekruti Hegde 1 , Somorat Bhattacharjee 1 , Manjunath s Pandit 2 , Lohith G 1

1 Radiation Oncology, Healthcare Global Hospital, Bengaluru, India. 2 Cardiology, Healthcare Global Hospital, Bangalore, India

Purpose/Objective:

To Study the Dose effect variations of 3DCRT, IMRT, HELICAL TOMOTHERAPY with hypofractionated regimen to the left anterior descending artery in early left breast cancer and to determine the role of ECG and 2D- ECHO as a predictive tool for cardiotoxicity.

Material/Methods:

In our study 135 patients with no history of cardiac comorbidities or prior history of thoracic irradiation diagnosed with early breast left sided breast cancer (stage IA,IB, IIA, IIB), underwent breast conservative surgery with or without adjuvant or neoadjuvant chemotherapy followed by treatment with radiation with hypofractionated schedule (Phase I : 40 Gy in 15 fractions over 5 days a week for 3 weeks and Phase II : 10Gy in 5 fractions over 5 days a week for 1 week) with either 3DCRT, IMRT or Helical tomotherapy were evaluated. Proximal and distal segments of left anterior descending artery(LAD) were contoured. Dmax and Dmean for proximal and distal LAD segments, LAD total mean dose and mean heart dose were calculated respectively. Baseline electrocardiogram (ECG) and echocardiogram (2D ECHO) of patients enrolled were obtained prior to the radiation treatment, at completion of radiation treatment (day 0) and at a mean follow-up of 2 months to ascertain our hypothesis that it can minimize the risk of ischemic heart disease.

Results:

LAD proximal max dose with 3DCRT is 38.91 ± 3.15, IMRT is 29.06 ± 2.91 and with helical tomotherapy is 16.88 ± 1.34. LAD proximal mean dose with 3DCRT is 4.87 ± 0.57, IMRT is 3.80 ± 0.24 and with helical tomotherapy is 2.24 ± 0.49. LAD distal Dmax with 3DCRT is 45.09 ± 2.29, IMRT is 37.98 ± 1.38 and helical tomotherapy is 26.13 ± 1.28. LAD distal mean dose with 3DCRT is 15.54 ± 1.16, IMRT is 13.13 ± 1.16 and with helical tomotherapy is 5.09 ± 0.41. LAD total mean dose with 3DCRT, IMRT and helical tomotherapy is 14.95 ± 1.28, 12.70 ± 1.41 and 4.86 ± 0.37. LAD