Cumulative dosimetric investigation based on image deformable registration in radiotherapy for cervical cancer / 中华放射肿瘤学杂志

Objective:To evaluate the differences in the cumulative doses for cervical cancer between two different methods, and analyze the correlation between the severity of radiation proctitis and the cumulative dose of the rectum.Methods.:Clinical data of 278 patients with cervical cancer treated with radiotherapy were retrospectively analyzed. The total dose of radiotherapy was calculated by simple dose volume histogram parameter accumulation method (S-DVH group) and dose accumulation by deformation image registration (DIR group) in 49 patients with radiation proctitis. The rectal cumulative dose of the 278 patients with S-DVH was counted(D 2.0cm 3/D 1.0cm 3/D 0.1cm 3). The correlation analysis was performed by Spearman’s correlation analysis. Results:The average cumulative dose(D 90%) difference of high-risk clinical target volume (HRCTV) between the S-DVH and DIR groups was 2 Gy (EQD 2Gy)[(88.66±5.75) vs. (86.66±5.54) Gy, P<0.05], and the average cumulative dose difference(D 2.0cm 3 and D 1.0cm 3) of bladder was 2.13 Gy[(82.46±6.91) vs.(80.33±6.86) Gy, P<0.05] and 2.35 Gy[(88.46±4.37) vs.(86.11±3.93) Gy, P<0.05], and the average cumulative dose difference(D 2.0cm 3 and D 1.0cm 3) of rectum was 1.99 Gy[(72.49±5.17) vs.(70.50±5.03) Gy, P<0.05] and 2.71 Gy[(78.87±4.50) vs.(76.16±4.14) Gy, P<0.05]. The rectal cumulative dose(D 2.0cm 3/D 1.0cm 3/D 0.1cm 3) was positively associated with the grade of radiation proctitis. Conclusions:The cumulative doses differ between two groups, and are equally in an acceptable range. S-DVH method is a relatively simple method to evaluate the cumulative exposure dose. The cumulative doses of the rectum(D 2.0cm 3/D 1.0cm 3/D 0.1cm 3) can be used to predict the incidence of radiation proctitis.

Accuracy of different image registration methods in image-guided adaptive brachytherapy for cervical cancer / 南方医科大学学报

OBJECTIVE@#To compare the accuracy of different methods for image registration in image-guided adaptive brachytherapy (IGABT) for cervical cancer.@*METHODS@#The last treatment planning CT images (CT1) and the first treatment planning CT images (CT2) were acquired from 15 patients with cervical cancer and registered with different match image qualities (retained/removed catheter source in images) and different match regions [target only (S Group)/ interested organ structure (M Group)/body (L Group)] in Velocity3.2 software. The dice similarity coefficient (DSC) between the clinical target volumes (CTV) of the CT1 and CT2 images (CTVCT1 and CTVCT2, respectively) and between the organs-at-risk (OAR) of the two imaging datasets (OARCT1 and OARCT2, respectively) were used to evaluate the image registration accuracy.@*RESULTS@#The auto-segmentation volume of the catheter source using Velocity software based on the CT threshold was the closest to the actual volume within the CT value range of 1700-1800 HU. In the retained group, the DSC for the OARs of was better than or equal to that of the removed group, and the DSC value of the rectum was significantly improved ( < 0.05). For comparison of different match regions, the high-risk target volume (HRCTV) and the low-risk target volume (IRCTV) had the best precision for registration of the target area, which was significantly greater than that of M group and L group ( < 0.05). The M group had better registration accuracy of the target area and the best accuracy for the OARs. The DSC values of the bladder and rectum were significantly better than those of the other two groups ( < 0.05).@*CONCLUSIONS@#The CT value range of 1700-1800 HU is optimal for automatic image segmentation using Velocity software. Automatic segmentation and shielding the volume of the catheter source can improve the image quality. We recommend the use of interested organ structures regions for image registration in image-guided adaptive brachytherapy for cervical cancer.

Role of Foxp3/Treg and RORγt/Th17 cell imbalance in rat model of chronic obstructive pulmonary disease / 中华危重病急救医学

Objective To observe the changes in forkhead/winged helix transcription factor p3(Foxp3), regulatory T cells(Treg),retinoid-related orphan receptor gamma(RORγt)in rat model of chronic obstructive pulmonary disease(COPD). Methods Twenty Sprague-Dawley(SD)rats were randomly divided into normal control group and COPD model group,with 10 rats in each group. The COPD model was reproduced by smoke inhalation and tracheal instillation of lipopolysaccharide(LPS),and no such treatment was conducted in normal control group. Twenty-eight days after the model reproduction,the pulmonary function was determined,the pathological changes of lung tissue were observed with haematoxylin-eosin(HE)staining,interleukins(IL-6,IL-10)in serum were detected by enzyme-linked immunosorbent assay(ELISA),CD4+CD25+Foxp3+Treg of peripheral blood was determined by flow cytometry,and the expressions of Foxp3,RORγt,IL-17 protein in lung tissue were assayed by Western Blot. Results Under light microscope,significal interstitial infiltration of inflammatory cells was found in alveoli and interstitial tissue of the lung,and destruction of alveolar tissue,alveolar wall thinning,and even rupture to fuse into bullae,and bleeding into alveoli in different degress could be observed. Compared with the normal control group,forced vital capacity(FVC),forced expiratory volume in 0.3 second(FEV0.3),FEV0.3/FVC,peak expiratory flow(PEF)in model group were significantly decreased〔FVC(mL):8.04±2.03 vs. 9.97±2.14,FEV0.3(mL):6.16±2.23 vs. 8.84±2.12,FEV0.3/FVC:0.70±0.09 vs. 0.85±0.11,PEF(mL/s):33.56±4.76 vs. 40.14±5.64, P<0.05 or P<0.01〕. Serum IL-6 was obviously increased(ng/L:93.17±20.96 vs. 76.28±13.24,P<0.05), IL-10 was significantly decreased(ng/L:78.62±15.17 vs. 104.34±19.46,P<0.01),and CD4+CD25+FoxP3+Treg was significantly diminished〔(2.75±0.83)% vs.(4.16±1.14)%,P<0.01〕in model group compared with those in the normal control group. The expression of Foxp3 protein in lung tissue in model group was significantly down-regulated compared with that in the normal control group(gray scale:0.38±0.15 vs. 0.63±0.11,P<0.01), and RORγt and IL-17 protein expressions were significantly up-regulated〔RORγt(gray scale):0.96±0.23 vs. 0.47±0.11,IL-17(gray scale):1.02±0.24 vs. 0.34±0.08,both P<0.01〕. Correlation analysis showed that FEV0.3 was positively correlated with Foxp3(r=0.585,P<0.05),and FEV0.3/FVC was negatively correlated with IL-6 and RORγt(r=-0.655,r=-0.607,both P<0.05). PEF was positively correlated with Treg(r=0.573, P<0.05),and negatively correlated with IL-17(r=-0.198,P<0.05). IL-6 was negatively correlated with Foxp3(r=-0.603,P<0.05),and positively correlated with RORγt(r=0.588,P<0.05). IL-10 was positively correlated with Treg(r=0.573,P<0.05). Treg was positively correlated with Foxp3(r=0.607,P<0.05), and negatively correlated with IL-17(r=-0.569,P<0.05). Foxp3 was negatively correlated with RORγt(r=-0.591, P<0.05). RORγt was positively correlated with IL-17(r=0.578,P<0.05). Conclusion There is a relationship among decreased pulmonary function,inflammation and imbalance of Foxp3/Treg and RORγt/Th17 in COPD.