宫颈癌骨髓保护根治性调强放疗技术剂量学研究

Dosimetric study of bone marrow-sparing intensity modulated radiotherapy in cervical cancer treated with definitive radiotherapy

目的分析宫颈癌骨髓保护调强放疗技术（BMS-IMRI）的物理剂量学特点,探讨其保护骨盆骨髓（PBM）的价值。方法选择接受根治性放疗的ⅡA-ⅢB期宫颈癌患者9例,分别设计BMS-IMRT和三维适形放疗（3D-CRT）计划进行治疗,BMS-IMRT计划要求骨盆骨受量符合以下标准：体积（V）10〈90%、V20〈76%、V40〈40%。结果与3D-CRT计划比较,BMSIMRT计划骨盆骨的V10、V20和V40均明显下降[（80.9±3.4）%vs.（93.2±2.7）%、（64.9±3.9）%vs.（87.8±3.2）%、（17.6±3.5）%vs.（31.9±4.1）%,P〈0.01];同时直肠、膀胱、小肠的剂量均明显下降（P〈0.01）。结论与3D-CRT计划比较,BMS-IMRT计划在不降低传统危及器官剂量限制标准的前提下,可明显的降低骨盆骨受量。

Objective To compare bone marrow-sparing intensity-modulated radiotherapy（BMS-IMRT）techniques with threedimension conformal radiotherapy（3D-CRT）techniques in cervical cancer treated with definitive whole pelvic radiotherapy,and to explore its advantage to protect the pelvic bone marrow.Methods Nine patients stagedⅡA-ⅢB cervical cancer were included.BMS-IMRT plans and 3D-CRT plans were created and compared.Dose constraints of pelvic bone for BMS-IMRT plans including：V1090%,V2076%,V4040%.Results Compared with 3D-CRT plans,BMS-IMRT plans significantly reduced the volume of pelvic bone at 10 Gy,20Gy,40 Gy dose levels[（80.9±3.4）%vs.（93.2±2.7）%,（64.9±3.9）%vs.（87.8±3.2）%,（17.6±3.5）%vs.（31.9±4.1）%,P〈0.01],while BMS-IMRT plans significantly reduced the volume of rectum,bowel,bladder at various dose levels（P〈0.01）.Conclusion BMS-IMRT plans significantly reduced the volume of pelvic bone marrow irradiated compared with 3D-CRT plans in patients with cervical cancer.In addition,BMS-IMRT did not compromise the sparing of other OARs.