摘要目的 探讨18F-FDG PET/CT显像评估马蔺子素(IR)对兔VX2肺癌模型放疗增敏作用的可行性.方法 建立24只兔VX2肺癌模型,按随机数字表法分为A(单纯放疗)组、B(IR+放疗)组及C(对照)组,每组各8只.各组分别于治疗前、治疗后24 h及治疗后1周行18F-FDG PET/CT显像,观察3组肿瘤部位延迟显像SUVmax的变化.显像完成后每组处死2只荷瘤兔,取出肿瘤组织,行HE染色观察病理改变.数据分析采用配对t检验、单因素方差分析及Kaplan-Meier生存分析.结果 全部兔VX2肺肿瘤放疗前PET/CT显像SUVmax为2.200±0.761,延迟显像SUVmax为3.162±0.833,差异有统计学意义(t=-5.582,P＜0.01).放疗后24hA、B、C组延迟显像SUVmax分别为2.614 ±0.654、2.349±0.869和5.663±1.144,3组与治疗前延迟显像SUVmax差异均有统计学意义(t=2.527、3.620和11.011,均P＜0.05)；放疗后1周时A、B、C组延迟显像SUVmax分别为3.625±1.064、3.058±0.850及7.424±1.751,各组间差异均有统计学意义(tA∶B=2.652、tA∶C=3.799和tB∶C=4.366,均P＜0.05),病理结果显示B组肿瘤细胞明显少于A、C组,与PET/CT结果相符.A、B、C3组生存时间分别为(62.375±4.534)、(69.000±4.660)和(54.125±5.276)d,Kaplan-Meier生存分析显示B组生存率较A组及C组明显增高(Log-rank检验,x2=7.355和16.943,均P＜0.01).结论 18F-FDG PET/CT可评估放疗早期疗效及马蔺子素对放疗的增敏作用.

abstractsObjective To evaluate the value of 18F-FDG PET/CT in assessing radiosensitivity enhancement by irisquinone (IR) on rabbit xenografted VX2 lung tumor models.Methods Twenty-four tumor-beating rabbits were randomly divided into 3 groups (8 rabbits/group):group A with radiotherapy alone,group B with combined radiotherapy and IR,and group C without radiotherapy (the control group).18F-FDG PET/CT imaging was performed before radiotherapy and 24 h and one week after radiotherapy.The tumor SUVmax on delayed imaging was calculated in all rabbits.Two rabbits in each group were sacrificed after PET/CT imaging.HE staining was used to assess the differences in cancer cells among groups.Paired t test,one-way analysis of variance and Kaplan-Meier analysis were performed to analyze the data using SPSS 13.0.Results Before radiotherapy,the tumor SUVmax of all the 24 rabbits on standard and delayed imaging were 2.200 ± 0.761 and 3.162 ± 0.833 (t =-5.582,P ＜ 0.01).At 24 h post-radiotherapy,the delayed SUVmax of groups A,B and C were 2.614 ± 0.654,2.349 ± 0.869 and 5.663 ± 1.144,respectively.The differences between pre-radiotherapy and 24 h post-radiotherapy were statistically significant in all three groups (t =2.527,3.620,11.011,all P ＜0.05).One week after radiotherapy,the delayed SUVmax of groups A,B and C were 3.625 ± 1.064,3.058 ±0.850 and 7.424 ± 1.751,respectively.The differences among groups A,B and C were statistically significant (tA∶ B =2.652,tA∶C =3.799,tB∶C =4.366,all P ＜0.05).The cancer cells of group B were fewer than those of groups A and C by pathological findings,which was consistent with 18F-FDG PET/CT results.The survival times of groups A,B and C were (62.375 ±4.534),(69.000 ±4.660) and (54.125 ±5.276) d,respectively.Kaplan-Meier survival curves revealed better survival of group B as compared to groups A and C,respectively (Log-rank,x2 =7.355,16.943,both P ＜ 0.01).Conclusion 18 F-FDG PET/CT is able to evaluate the effect of irisquinone on tumor radiosensitivity enhancement.