Intra- and inter-fraction breath-hold variations and margins for radiotherapy of abdominal targets.

ABSTRACT: Radiotherapy in expiration breath-hold (EBH) has the potential to reduce treatment volumes of abdominal targets compared to an internal target volume concept in free-breathing. The reproducibility of EBH and required safety margins were investigated to quantify this volumetric benefit. Pre- and post-treatment diaphragm position difference and the positioning variability were determined on computed tomography. Systematic and random errors for EBH position reproducibility and positioning variability were calculated, resulting in margins of 7 to 12 mm depending on the prescription isodose and fractionation. A reduced volume was shown for EBH for lesions with superior-inferior breathing motion above 4 to 8 mm.

SUBMITTER: Ehrbar S 

PROVIDER: S-EPMC10692905 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature