ESTRO 2024 - Abstract Book

S6006

RTT - Treatment planning, OAR and target definitions

ESTRO 2024

The IMRT, Hybrid-IMRT and Hybrid-VMAT techniques demonstrated potential advantages over FiF in most of the evaluated parameters in this study.

VMAT, according to the data from this study, presented significantly worse results in most of the evaluated parameters. However, other treatment planning settings can be carried out to confirm this assumption. The robustness of the plan may also have an influence on the result.

A larger sample will be needed to confirm the results of this study. Breath-hold techniques in breast treatment make the beam-on time with the addition of the machine set-up a weighty criterion to evaluate in the next study.

Keywords: treatment plan, breast cancer, ultrahypofraction

References:

1. Early Breast Cancer Trialists’ Collaborative Group (EBCTCG) et al. Effect of radiotherapy after breast-conserving surgery on 10-year recurrence and 15-year breast cancer death: meta-analysis of individual patient data for 10,801 women in 17 randomised trials. Lancet Lond. Engl. 378, 1707–1716 (2011).

2. Offersen, B. V. et al. ESTRO consensus guideline on target volume delineation for elective radiation therapy of early stage breast cancer. Radiother. Oncol. 114, 3–10 (2015).

3. Brunt, A. M. et al. Hypofractionated breast radiotherapy for 1 week versus 3 weeks (FAST-Forward): 5-year efficacy and late normal tissue effects results from a multicentre, non-inferiority, randomised, phase 3 trial. The Lancet 395, 1613–1626 (2020).

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Digital Poster

SINGLE VS DOUBLE-ISOCENTRIC VMAT THERAPY TECHNIQUE FOR SYNCHRONOUS BILATERAL BREAST CANCER

Adriana Martins, Ana Luisa Vasconcelos

Fundação Champalimaud, Radiotherapy, Lisbon, Portugal

Purpose/Objective:

Incidence of bilateral breast cancer (BC) is 2-11%: the synchronous tumours represent approximately 0.6%. Incidence is increasing as a result of advances in BC imaging, genetic predisposition or exposure to environmental risk factors. Adjuvant radiation therapy (RT) for synchronous bilateral breast cancer (sBBC) often represents a complex planning challenge. This review compares dosimetrically parameters and treatment specificities in hypofractionated simultaneous integrated boost plans with single or double isocenter technique.