骨盆骨髓剂量限定调强放疗同步化疗治疗淋巴结阳性宫颈癌患者的剂量学研究

Dosimetry of pelvic bone marrow sparing intensity modulated radiotherapy simultaneous chemotherapy in patients with lymph node-positive cervical cancer

目的比较骨盆骨髓剂量限定调强放疗(PBMS-IMRT)和调强放疗(IMRT)治疗淋巴结阳性宫颈癌患者的剂量学参数及血液不良反应。方法将40例ⅡA~ⅣB期盆腹淋巴结阳性宫颈癌初治患者按照随机数字表法分为PBMS-IMRT组和IMRT组,每组20例,对PBMS-IMRT组患者进行骨盆剂量限制,IMRT组不进行骨盆剂量限制,两组放疗后均进行同步化疗。观察两组患者的靶区剂量学参数、危及器官剂量学参数、骨盆剂量学参数及血液不良反应。结果PBMS-IMRT组患者计划肿瘤体积(PTV)靶区剂量中不均匀指数(HI)与适形指数(CI)均高于IMRT组,差异均有统计学意义(P﹤0.05)。PBMS-IMRT组患者膀胱平均剂量(D_(mean))低于IMRT组,差异有统计学意义(P﹤0.05)。PBMS-IMRT组患者骨盆最大剂量(D_(max))、D_(mean)、最小剂量(D_(min))及V_(5)、V_(10)、V_(20)、V_(30)、V_(40)、V_(50)均低于IMRT组,差异均有统计学意义(P﹤0.05)。PBMS-IMRT组患者血液不良反应发生情况明显优于IMRT组,差异有统计学意义(P﹤0.01)。结论PBMS-IMRT同步化疗治疗淋巴结阳性宫颈癌患者能有效提高靶区的适形度,且对其他危及器官的受量无明显影响,通过进行骨盆剂量限制,明显降低血液不良反应发生率。

Objective To compare the dosimetry and hematotoxicity of pelvic bone marrow sparing intensity modulated radiotherapy(PBMS-IMRT)and intensity modulated radiotherapy(IMRT)in patients with lymph node-positive cervical cancer.Method A total of 40 patients with pelvic lymph node-positive cervical cancer in IIA-IVB stage were randomly divided into the PBMS-IMRT group(n=20)and IMRT group(n=20).Pelvic dose restriction was performed in PBMS-IMRT group and no pelvic dose restriction in IMRT group,and both groups received simultaneous chemotherapy after radiotherapy.The target dosimetric index,dosimetric difference of endangered organs,pelvic dose parameters and hematotoxicity were observed.Result Conformity index(CI)and homogeneity index(HI)among the planned target volume(PTV)in PBMS-IMRT group were significantly better than those in IMRT group(P<0.05);the mean dose(D_(mean))of bladder in PBMS-IMRT group was significantly lower than that in IMRT group(P<0.05);the maximum dose(D_(max)),D_(mean),minimum dose(D_(min))of pelvis irradiation,V_(5),V_(10),V_(20),V_(30),V_(40) and V_(50) in PBMS-IMRT group were significantly lower than those in IMRT group(P<0.05);and the incidence of hematotoxicity in PBMS-IMRT group was significantly lower than those in IMRT group(P<0.01).Conclusion PBMS-IMRT simultaneous chemotherapy can effectively improve the conformal degree of the target area in patients with lymph node-positive cervical cancer,and has no obvious damage to other endangered organs.The incidence of hematotoxicity can be significantly reduced by pelvic dose restriction.