ESTRO 2022 - Abstract Book

S656

Abstract book

ESTRO 2022

for CB, and 0.98 for SB (p=0.044); median HI was 0.27 for CB, and 0.29 for SB (p=0.0007). The SL V95%, V98%, V100%, V105% were negligible in both groups, with complete absence of V105% in the CB one. Rival plans CB versus SB for the 45 women receiving sequential boost showed negligible SL dose, too, regardless of the timing of boost, and no differences in the lung and heart sparing.

Conclusion Tumor bed field-in-field CB is cost-effective, may improve outcomes of breast-conserving RT with easy implementation, ensures a more homogeneous target volume dose distribution, negligible SL doses with lower toxicity profile than SB, and shortened overall treatment time. The integration of dosimetric data with cosmetic results will further clarify our promising findings.

PD-0744 Tangential fields in pN+ sentinel nodes breast cancer with or without axillary dissection.

M. Borgia 1 , M. Nuzzo 1 , L.A. Ursini 1 , C. Rosa 1,2 , F.C. Di Guglielmo 1 , M. Lucarelli 1 , D. Fasciolo 1 , D. Genovesi 1,2

1 SS. Annunziata Hospital, Department of Radiation Oncology, Chieti, Italy; 2 G. D’Annunzio University, Department of Neuroscience, Imaging and Clinical Sciences, Chieti, Italy

Purpose or Objective