Intrafractional Target Motions and Uncertainties of Treatment Setup Reference Systems in Accelerated Partial Breast Irradiation

摘要: Purpose This study investigated the magnitude of intrafractional motion and level accuracy various setup strategies in accelerated partial breast irradiation (APBI) using three-dimensional conformal external beam radiotherapy. Methods materials At lumpectomy, gold fiducial markers were strategically sutured to surrounding walls cavity. Weekly fluoroscopy imaging was conducted at treatment investigate respiration-induced target motions. Daily pre- post-RT kV performed, images matched digitally reconstructed radiographs based on bony anatomy markers, respectively, determine magnitudes over course treatment. The positioning differences laser tattoo- anatomy-based setups compared with those marker-based (benchmark) also determined. included 21 patients. Results Although lung exhibited significant motion, average marker amplitude fluoroscopic image about 1 mm. Over a typical time period, 4.2 mm 2.6 matching, respectively. anatomy- tattoo-based interfractional errors, respect setup, 7.1 9.0 mm, Conclusions Respiration has limited effects during APBI. Bony improves relative that approach. Since are directly surgical cavity, approach can further improve accuracy. On average, seroma cavity exhibits more than 4 is larger which otherwise derived matching. A seroma-specific potential by taking true inter- motions into consideration.