Dose distribution analysis of whole body γ-knife and three-dimensional conformal radiotherapy in treatment of primary hepatic carcinoma / 医疗卫生装备

ABSTRACT

Objectives To compare the dose distribution of the whole body γ-knife and three-dimensional conformal radiotherapy (3D-CRT) in the treatment of primary hepatic carcinoma to provide evidence for clinical treatment choice.Methods Totally 35 patients with primary hepatic carcinoma treated with whole body γ-knife from March 2014 to July 2015 underwent three-dimensional conformal radiotherapy planning,and dose volume histograms were used to evaluate the dose distribution of target volumes and normal tissue,and moreover conformity index (CI) and homogeneity index (HI) were analyzed.Results Between the two treatment plans,D98 and the mean dose Da of GTV were higher in whole body γ-knife plan than those in three-dimensional conformal radiotherapy plan.For PTV,the V95 of γ-knife and three-dimensional conformal radiotherapy were (95.05±0.02)％ and (90.00±0.03)％ (P=0.00) respectively.Target coverage of whole body γ-knife was better.For organ at risk,γ-knife showed better protection of normal tissue.Three-dimensional conformal radiotherapy showed better HI (GTV0.11±0.15 vs 0.23±0.02,PTV0.14±0.04 vs 0.21±0.03),while more normal liver tissue received excessive exposure.The whole body γ-knife increased dose of target volumes and decreased dose of normal tissue,while three-dimensional conformal radiotherapy showed better HI.Conclusion Compared with three-dimensional conformal radiotherapy,the whole body γ-knife shows advantage in dose distribution but HI of target volumes.For clinical using,appropriate treatment needs to be chosen according to the patients' actual situation.