Target tailoring and proton beam therapy to reduce small bowel dose in cervical cancer radiotherapy : A comparison of benefits.

摘要: The aim of the study was to investigate potential clinical benefit from both target tailoring by excluding tumour-free proximal part uterus during image-guided adaptive radiotherapy (IGART) and improved dose conformity based on intensity-modulated proton therapy (IMPT). included planning CTs 11 previously treated patients with cervical cancer a >4-cm diagnostic magnetic resonance imaging (MRI). IGART robustly optimised IMPT plans were generated for conventional volumes MRI-based (where non-invaded excluded), yielding four treatment per patient. For each plan, V15Gy, V30Gy, V45Gy Dmean bladder, sigmoid, rectum bowel bag compared, normal tissue complication probability (NTCP) ≥grade 2 acute small toxicity calculated. Both resulted in significant reductions bladder bowel. reduced NTCP 25% 18%; this further 9% when combined tailoring. In 11 patients (36%), >10% estimated IMPT, six (55%) This reduction expected if >275 cm3 >200 cm3, respectively, standard alone. cancer, lead a significant surrounding organs at risk toxicity.