Predicting adherence of dose–volume constraints for personalized partial-breast irradiation technique

PurposeMulticatheter interstitial brachytherapy (MIB) and external-beam (EB) radiotherapy are established partial-breast irradiation (PBI) techniques. Although EB-PBI is widely available, it requires extra irradiated margins for target uncertainties. We examined the impact of on dose–volume constraints as compared to MIB-PBI.Methods MaterialsAmong 653 patients receiving MIB-PBI between October 2008 April 2020, consequent 159 after September 2018 were examined. Clinical volume (CTV) included lumpectomy cavity plus 1.0 cm. Planning (PTV) was defined CTV with 1.0-cm expansion. Because ratio PTV breast (RPB) related cosmesis, <25% RPB suitable ipsilateral constraints. Preoperative size classified very small (<350 cm3), (350–699 medium or large (≥700 cm3). According each category, organs at risk two PBI techniques.ResultsPatients including 84 small, 59 16 moderate breasts in all MIB-PBI, achieved 74 (46.5%) (p < 0.0001). The 32.1%, 55.9%, 100%, respectively Normal-tissue other could be satisfied breasts.ConclusionAlthough may an appropriate option breasts, still a crucial technique, especially breasts.