Abstract
INTRODUCTION
In this study, we adjusted lung and breast cancer patient’s positioning by using body surface scanning system. We compared CBCT scan's results deviation for 12 patients during 200 fractions and we investigated intra-fraction motion of patients.
METHODS
Lung cancer patient's radiotherapy treatment planning were performed with VMAT, breast cancer's patients with IMRT method while using 3,0 mm thickness CT slices. Couch shifts were performed while using C-RAD body surface scanning system during 200 fractions in the treatment room, then patient's CBCT scans were performed. We obtained body surface guided scanning system and CBCT scan correlation. Intra-fraction motion was obtained during treatment for each patient while using body surface guided.
RESULTS
Couch shift parameters were obtained in lateral direction 0,22±0,07cm, longitudinal direction 0,28±0,08cm and vertical direction 0,30±0,10cm during 87 fractions for 7 lung cancer patients. Correlation results were obtained in lateral direction 0,22±0,06 cm, longitidunial direction 0,25±0,03 cm and vertical direction 0,21±0,08 cm during 113 fractions for 5 breast cancer patients. We determined intra-fraction motion 0,7±0,4mm in 0-1min. interval, 1,5±0,5mm in 1-2min. interval, 2,4±0,7mm in 2-3min. interval, 3,1±0,6mm in 3-4min. interval, 3,8±0,7mm in 4-5min. interval and 4,1±1,4mm in 5-6min. interval for 7 lung cancer patients.We obtained intra-fraction motion 0,6±0,1mm in 0-1min. interval, 1,6±0,2mm in 1-2min. interval, 2,6±0,5mm in 2-3min. interval, 3,2±0,4mm in 3-4min. interval, 3,8±0,7mm in 4-5min. interval, 4,2±0,4mm in 5-6min. and 4,4±0,7mm in 6-7min. interval for 7 lung cancer patients.
DISCUSSION AND CONCLUSION
Correlation between body surface guided system posioning and CBCT positioning were obtained an average less than 0.3cm for lung and breast cancer patients during 200 fractions. Reducing the ionisation radiation for patient positioning with body surface guided system were obtained feasible for lung and breast cancer radiotherapy.