螺旋断层固定野调强放疗技术在中段食管癌放疗中的应用

目的 探究螺旋断层固定野调强放疗TomoDirect(TD)技术在中段食管癌放疗中的应用,并评价计划质量和效率。方法 对本院收治的10例局部晚期根治性中段食管癌患者进行研究。分别在TomoTherapy和Pinnacle³计划系统设计TD、螺旋断层调强放疗(HT)和常规加速器固定野调强放疗(IMRT)计划。比较3种计划的靶区适形度指数(CI)、均匀性指数(HI)和危及器官(OARs)受量以评价计划质量;比较治疗时间和机器跳数(MU)以评价治疗效率。结果 与IMRT计划相比,TD和HT计划的靶区CI和HI具有剂量学优势(t=5.261、10.419、-5.463、-6.862,P<0.05);与HT计划相比,TD计划的靶区CI和HI要差(t=-7.055、2.325,P<0.05)。与IMRT计划相比,TD和HT计划的平均双肺V₂₀、V₃₀和平均剂量显著变低(t=-5.372、-6.296、-5.372、-6.296、-2.865、-4.632,P<0.05)。与HT计划相比,TD和IMRT计划的心脏平均剂量要低(t=-3.112、2.829,P<0.05)、心脏最大剂量要高(t=3.154、-3.348,P<0.05)。与HT计划相比,TD计划的脊髓最大剂量和正常组织平均剂量要高(t=3.071、5.076,P<0.05)。与HT计划相比,TD平均治疗时间和机器跳数减少12.0%和37.2%(t=-4.095、-12.559,P<0.05),IMRT计划的治疗时间最短。结论 TD技术应用于中段食管癌放疗具有一定优势,与HT技术相比,TD射线利用率高,治疗时间短;与IMRT技术相比,TD靶区CI、HI以及平均双肺V₂₀、V₃₀和平均剂量具有明显的剂量学优势。

TomoDirect in the clinical implementation of mid-esophageal carcinoma

Objective To evaluate the use of TomoDirect (TD) for the treatment of esophageal cancer in terms of plan quality and treatment efficiency. Methods In total of ten patients for locally advanced esophageal cancer with radical intent were planned for TD, Helical tomotherapy (HT) and IMRT, where TD and HT plans were designed in TomoTherapy and IMRT plans in Pinnacle³. Dose conformity index (CI), dose homogeneity index (HI) and dose for OARs were analyzed to evaluate the plan quality. Treatment time and monitor units were used to assess delivery efficiency. Results TD and HT plans showed significant improvement over IMRT plans in terms of CI and HI (t=5.261,10.419,-5.463,-6.862,P<0.05). TD plans had a little worse CI and HI than those of HT plans (t=-7.055, 2.325, P<0.05). Mean V₂₀, V₃₀ and averaged dose of lungs were significantly improved by TD and HT plans in comparison with IMRT plans (t=-5.372, -6.296, -5.372, -6.296, -2.865, -4.632, P<0.05). Compared with HT plans, the averaged dose of heart was worse than those of TD and IMRT plans (t=-3.112, 2.829, P<0.05), while the maximum dose of heart was better than those of TD and IMRT plans (t=3.154, -3.348, P<0.05). The maximum dose of cord and averaged dose of normal tissue for TD were worse than that of HT plans (t=3.071, 5.076, P<0.05). The treatment time and machine monitor unit of TD plans was reduced by 12.0% and 37.2% compared with HT plans, respectively (t=-4.095, -12.559, P<0.05). IMRT plans had the shortest treatment time. Conclusions The TD technique is feasible to treat esophageal cancer. It not only can reduce the treatment time and improve radiation efficiency compared with HT, but also provide an advantage in terms of CI and HI, and V₂₀, V₃₀ and averaged dose of lungs in comparison with IMRT.