MRI指导的骨髓保护调强放疗在宫颈癌术后同步放化疗中的应用研究

Application of MRI-guided bone marrow protection intensity-modulated radiotherapy in concurrent radiotherapy and chemoradiotherapy after cervical cancer surgery

目的探讨在宫颈癌术后同步放化疗中采用磁共振成像(MRI)指导的骨髓保护调强放疗(BMS-IMRT)对减轻血液学毒性效果。方法选取2018年6月至2021年6月该院接受宫颈癌手术并行术后放化疗的102例患者为研究对象,所有患者采取MRI与定位CT融合勾画造血活性骨髓并进行剂量限定的调强放疗(IMRT)。所有患者按照入院时间分为IMRT组(66例)和BMS-IMRT组(36例),比较两组剂量学参数、急性血液毒性及不良反应发生情况。结果BMS-IMRT组适形性指数(CI)和均匀性指数(HI)分别为0.07±0.00、0.87±0.06,与IMRT组CI(0.07±0.01)和HI(0.89±0.05)比较,差异无统计学意义(P>0.05)。BMS-IMRT组骨髓V_(5)、V_(10)和V_(20)较IMRT组明显减少,差异有统计学意义(P<0.05);两组骨髓V_(30)、V_(40),以及直肠、膀胱V_(30)、V_(40)和V_(45)比较,差异无统计学意义(P>0.05)。BMS-IMRT组2级以上血液学毒性总体发生率低于IMRT组,差异有统计学意义(P<0.05)。受试者工作特征(ROC)曲线分析IMRT组2级以上急性血液学毒性发生相关骨髓限量的临界值,发现造血活性骨髓的V_(5)、V_(10)、V_(20)与2级以上血液学毒性发生有关,最佳截断值分别为92.01%、83.92%和72.71%,其曲线下面积分别为0.814、0.698和0.746。两组不良反应发生情况比较,差异无统计学意义(P>0.05)。结论BMS-IMRT可降低2级以上急性血液毒性发生率。

Objective To investigate the effect of bone marrow spared intensity-modulated radiation therapy(BMS-IMRT)guided by magnetic resonance imaging(MRI)on the reduction of hematological toxicity in concurrent chemoradiotherapy after cervical cancer surgery.Methods A total of one hundred and two patients who received cervical cancer surgery and postoperative chemoradiotherapy from June 2018 to June 2021 were selected.All patients were treated with MRI and localized CT fusion to delineate hematopoietic active bone marrow and dose limited intensity modulated radiotherapy(IMRT).The patients were divided into the IMRT group(66 cases)and the BMS-IMRT group(36 cases)according to the time of admission.The dosimetric parameters,acute blood toxicity and adverse reactions of the two groups were compared.Results Conformity index(CI)and homogeneity index(HI)in the BMS-IMRT group were 0.07±0.00 and 0.87±0.06,respectively.There was no significant difference compared with CI(0.07±0.01)and HI(0.89±0.05)in the IMRT group(P>0.05).Compared with the IMRT group,bone marrow V_(5),V_(10)and V_(20)in the BMS-IMRT group decreased significantly(P<0.05);There was no significant difference in bone marrow V_(30),V_(40),rectum,bladder V_(30),V_(40)and V_(45)between the two groups(P>0.05).The overall incidence of hematologic toxicity of above grade two in the BMS-IMRT group was lower than that in the IMRT group,with a statistically significant difference(P<0.05).By analyzing the critical value of bone marrow limit related to the occurrence of acute hematological toxicity above grade 2 in the IMRT group with ROC curve,it was found that V_(5),V_(10)and V_(20)of hematopoietic active bone marrow were related to the occurrence of hematological toxicity above grade 2.The optimal cutoff values were 92.01%,83.92%,and 72.71%respectively,and the area under the curve was 0.814,0.698,and 0.746 respectively.There were no statistical difference in the occurrence of adverse reactions between the two groups(P>0.05).Conclusion Bone marrow-spared IMRT can reduce the incidence of acute hematological toxicity above grade two.