【摘要】 目的比较颈段、胸上段食管癌常规放疗(CRT)、三维适形放疗(3D-CRT)、调强放疗(IMRT)累及野放疗中靶区和危及器官(OAR)的剂量学差异,进而为临床治疗选择最优放射治疗方案;比较不同大小肿瘤(直径<3 cm及>5 cm)不同放疗计划对危及器官的影响,进而选择较优的放疗计划。方法选择12例颈段及胸上段食管癌患者,应用三维治疗计划系统(TPS)分别为每位患者设计三种治疗计划(A.常规放疗;B三维适形放疗;C调强适形放疗),在规定CTV至少达到95%处方剂量前提下根据剂量体积直方图(DVH)、等剂量曲线比较三种计划靶区剂量分布及脊髓、气管、肺正常组织受量的差异;同时比较不同大小的肿瘤三种放疗计划对脊髓的剂量学影响。结果三种计划的靶区的平均剂量以IMRT计划为好,IMRT同时减少了脊髓及气管的剂量,差异有统计学意义(P<0.05);不管肿瘤直径大小,以IMRT计划最好。结论颈段及胸上段食管癌采用调强适形放疗,能在提高靶区剂量的同时更好的保护周围正常组织及器官,较三维适形放疗有剂量学优势,是目前较好的一种放疗方法。更多还原

【Abstract】 Objective To compare the dosimetry differences of CRT,3-dimensional conformal radiation therapy(3D-CRT) and intensity modulated radiation therapy( IMRT) for choosing the best treatment program for patients with cervical and upper esophageal carcinoma, and to compare effects of radiotherapy of different tumor sizes( diameter < 3 cm and > 5 cm) on organs for selection of the optimum plan. Methods Twelve patients with cervical and upper esophageal carcinoma were treated with three kinds of treatment programs(CRT,3-dimensional conformal radiation therapy and intensity modulated radiation therapy) within the same TPS. The differences of exposure dose between target area and critical organ were compared with dose volume histogram( DVH) and isodose,with the clinical target volume( CTV) up to above 95% of the prescription dose;At the same time,the effects on the spinal cord were compared among three kinds of radiation dosimetry program for different sizes of the tumor. Results IMRT plan was the best in the average dose in target area,which showed significant difference in reducing the dose at the spinal cord and trachea( P < 0. 05). IMRT was the best plan regardless of the size of the tumor diameter. Conclusions Cervical and upper thoracic esophageal cancer using intensity modulated conformal radiotherapy can better protect the surrounding normal tissues and organs when the target dose increases,which has dosimetry advantage over three-dimensional conformal radiotherapy and becomes a better radiotherapy.更多还原