Evaluating the influence of 6 MV and 15 MV photon beams on prostate intensity-modulated radiation therapy plans

作     者：Reham A.El Gendy Ehab M.Attalla Yasser M.Elkerm Ali Alfarrash 

作者机构：Ayadi Al Mostakbl 0ncology CenterAlexandriaEgypt National Cancer InstituteCairo UniversityCairoEgypt Cancer Management and Research DepartmentMedical Research InstituteAlexandria UniversityAlexandriaEgypt Faculty of ScienceMansoura UniversityMansouraEgypt 

出 版 物：《Oncology and Translational Medicine》 (肿瘤学与转化医学（英文版）)

年 卷 期：2016年第2卷第1期

页      面：26-33页

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

主　　题：intensity-modulated radiation therapy (IMRT) mixed-energy plans 6 MV 15 MV prostate cancer radiation treatment planning dose-volumetric analysis 

摘      要：Objective We aimed to determine the ef ects of low- and high-energy intensity-modulated radiation therapy （IMRT） photon beams on the target volume planning and on the critical organs in the case of prostate can-cer. Methods Thirty plans were generated by using either 6 MV or 15 MV beams separately, and a combination of both 6 and 15 MV beams. Al plans were generated by using suitable planning objectives and dose con-straints, which were identical across the plans, except the beam energy. The plans were analyzed in terms of their target coverage, conformity, and homogeneity, regardless of the beam energy. Results The mean percentage values of V70 Gy for the rectal wal for the plans with 6 MV, 15 MV, and mixed-energy beams were 16.9%, 17.8%, and 16.4%, respectively, while the mean percentage values of V40 Gy were 53.6%, 52.3%, and 50.4%. The mean dose values to the femoral heads for the 6 MV, 15 MV, and mixed-en-ergy plans were 30.1 Gy, 25.5 Gy, and 25.4 Gy, respectively. The mean integral dose for the 6 MV plans was 10% larger than those for the 15 MV and mixed-energy *** These preliminary results suggest that mixed-energy IMRT plans may be advantageous with respect to the dosimetric characteristics of low- and high-energy beams. Although the reduction of dose to the organs at risk may not be clinical y relevant, in this study, IMRT plans using mixed-energy beams exhibited better OAR sparing and overal higher plan quality for deep-seated tumors.