ESTRO 2024 - Abstract Book

S495

Clinical - Breast

ESTRO 2024

In FB (n=80), the Dmean of contralateral IMN CTV was significantly higher than in those with DIBH (n=40; 13.9 Gy vs. 11.2 Gy; p=.002).

Mean dose to the heart and lungs were 4.3 Gy and 8.2 Gy with both organs being significantly reduced by DIBH.

Conclusion:

The incidental dose to the contralateral IMN during adjuvant breast cancer irradiation is low irrespective of irradiation technique and target volume. Therefore, a therapeutic effect of the incidental dose distribution is unlikely. Potential implications should be addressed in further trials.

Keywords: Contralateral IMN, Incidental Dose, DIBH

References:

1. Rouvière, H., Anatomie des lymphatiques de l'homme [Texte imprimé] / H. Rouvière. 1932, Paris: Masson et Cie.

2.

Bourgeois, P. and J. Fruhling, Contralateral internal mammary node invasion in breast cancer:

lymphoscintigraphic data. Breast, 1999. 8(3): p. 107-9.

3. Scatarige, J.C., et al., Internal mammary lymphadenopathy in breast carcinoma: CT appraisal of anatomic distribution. Radiology, 1988. 167(1): p. 89-91.

4. Singh, S., et al., Incidence of internal mammary node in locally advanced breast cancer and its correlation with metastatic disease: a retrospective observational study. Br J Radiol, 2019. 92(1103): p. 20190098.

5. Offersen, B.V., et al., ESTRO consensus guideline on target volume delineation for elective radiation therapy of early stage breast cancer. Radiother Oncol, 2015. 114(1): p. 3-10.