The role of 18F-FDG PET/CT in evaluation of radiosensitivity enhancement by irisquinone / 中华核医学与分子影像杂志

ABSTRACT

Objective 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.