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Objective:To explore the application of ArcCheck system in the validation of Helical and Direct tomotherapy plans for esophageal cancer and summarize relevant experience.Methods:The Helical and Direct tomotherapy verification plans were established for 32 patients with esophageal cancer at different positions according to the doctor′s instructions, which were verified by the ArcCHECK system to compare the passing rate of the results.The correlation between the volume of the target area and the passing rate of the planned verification was analyzed. The therapeutic verification plan with a small target volume was made. The target area was placed at the center of ArcCHECK phantom and the area of detectors to statistically compare the verification passing rates.Results:Helical plan showed a significantly higher passing rate than the Direct plan ( P<0.01). The correlation coefficients between the target volume and the passing rate of the Helical and Direct plans were -0.364 and -0.042, and the P values were 0.041 and 0.819, respectively. For the Helical plan, when the 3%/2mm criterion was adopted, there was significant difference between placing the high-dose area at the center of the phantom and the area of detectors ( P=0.005), and the passing rate of the latter was higher. There was no significant difference in the other cases (all P>0.05). Conclusions:The passing rate of the Helical plan is generally higher than that of the Direct plan, which may be related to the angular response of the ArcCHECK detector and the fact that more reference points are not included for calculation due to low-dose radiation. In addition, it may also be related to the higher requirements of Direct plan for tomotherapy dose control system. In the Helical verification plan, when the 3%/3mm criterion is adopted, the larger the target volume, the higher the possibility of lower passing rate, whereas the correlation coefficient between them is relatively low. The high-dose area can be verified by the plans at the center of the phantom or the detection point. With the comprehensive consideration, we suggest putting it at the center of the phantom.
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Objective To analyze setup errors and guide the calculation of margins from clinical target volume (CTV) and planning target volume (PTV) in esophageal cancer patients treated with tomothcrapy by the MVCT image-guided system.Methods Sixty-four esophageal canccr patients trcated with tomotherapy in our hospital in 2016 were randomly selected.MVCT images were acquired after patients' positioning and co-registered with KVCT images.The setup errors of x,y,and z translations and roll rotation were analyzed with the t-test or one-way ANOVA.Meanwhile,PTV margin was calculated based on the formula of M =2.5 Σ + 0.7δ Results According to the formula,the CTV-PTV margins in the x,y and z directions are slightly different between cancers located in the cervical,upper thoracic,middle thoracic,and lower thoracic segments.In patients with upper thoracic esophageal cancer,the average setnp error in the yaxis was lower when the head-neck-shoulder thermoplastic film fixation was used than when somatic thermoplastic film fixation (P=0.000);the setup errors of z-axis with somatic thermoplastic film fixation in the fifth and sixth weeks were slightly less than those in the first several weeks (P =0.036);the setup errors acquired by three image registration patterns were similar (x-axis P=0.868,y-axis P=0.491,z-axis P=0.169,roll P=0.985).Conclusions In the treatment of patients with esophageal cancer,the setup errors are large,but the MVCT in the TOMO HD system can greatly reduce the setup errors,ensuring the accuracy of each treatment.It is further recommended that in clinical practice,different CTV-PTV margins should be used for the treatments of esophageal cancers located in different segments.Patients with upper thoracic esophageal cancer are advised to use the head-neck-shoulder thermoplastic film fixation.
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Objective To compare the setup errors of two position fixation, head-neck-shoulders immobilization system and trunk immobilization system in radiotherapy for esophageal cancer, and to provide technical guidance for the fixed modes and determination of plan target volume (PTV) in the intensity modulated radiation therapy (IMRT) of esophageal cancer. Methods 97 thoracic esophageal cancer patients treated with radiotherapy were collected and divided into two groups: head-neck-shoulders group (51 patients immobilized with head-neck-shoulders immobilization system) and trunk group (the other 46 patients immobilized with trunk immobilization system). Before the weekly radiotherapy, all the patients received cone-beam CT (CBCT) scan to get the setup errors of X axis (left and right), Y axis (head and foot) and Z axis (front and back) on line. Results In the head-neck-shoulders group, the errors in X, Y and Z direction were (0.333 ±0.400) cm, (0.333 ±0.291) cm and (0.238 ±0.256) cm, respectively. In trunk group, the errors were (0.327±0.255) cm, (0.582±0.501) cm and (0.189±0.154) cm, respectively. There were statistically significant differences in the setup errors in Y axis and Z axis between the head-neck-shoulders group and the trunk group (P< 0.05). Conclusions In the radiotherapy for thoracic esophageal carcinoma, there is no difference in the X axis setup error between head-neck-shoulders system and trunk immobilization system. The Y axis setup error of head-neck-shoulders group is less than that of the trunk group. The Z axis setup error of trunk group is less than the head-neck-shoulders group.
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Objective To explore the correlation between liver injury,fibrosis and levels of serum interleukin(IL)-18,transforming growth factor(TGF)-β1,and HBV DNA in patients with chronic hepatitis B(CHB).Methods Sixty-seven CHB cases were collected as experimental group and 20 healthy controls were enrolled as healthy control group.Serum levels of IL-18 and TGF-β1 were analyzed using enzyme linked immunosorbent assay(ELISA),and serum HBV DNA level was measured by fluorescent quantitative polymerase chain reaction(PCR).Liver biopsy was performed in 48 cases.Data analysis was done by variance analysis and data with heterogeneity of variance were analyzed by rank sum test.Partial correlation was employed to analyze the correlations between different data.Results The serum levels of IL-18,TGF-β1,alanine aminotransferase(ALT)and total bilirubin(TBil)were all higher in patients with hepatitis B and cirrhosis than those in controls(P<0.01).With the progression of liver injury,the levels of IL-18 and TGF-β1 were correspondingly increased,and the differences of TGF-β1 level between different groups were statistically significant(P<0.01),with the highest level in the patients with liver cirrhosis.There was no significant difference of the levels of ALT and TBil between the high and low viral load groups,but compared with control group,the differences were both significant(F=10.970,F=7.528;F=14.698,F=13.395;all P<0.05).TGF-β1 level gradually increased with fibrosis stage of CHB increasing from SO to S4,and there were significant differences between two stages except S3 and S4(P<0.01 or P<0.05).The difference of IL-18 level was only significant between SO stage and other stages.There was no significant difference of HBV DNA level among all stages. Partial correlation analysis indicated that IL-18 positively correlated with ALT and TBil(r=0.4806 and r=0.5047,respectively,both P<0.01).HBV DNA had no correlation with IL-18,TGF-β1,ALT and TBil.Conclusions Serum IL-18 and TGF-β1 levels play important roles in the progression of liver injury.Serum TGF-β1 level is correlated closely with post-hepatitis cirrhosis. Serum HBV DNA level is not significantly correlated with liver injury and fibrosis.
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Aim To investigate the impact of UVA on expression of tumour necrosis factor related apoptosis inducing ligand (TRAIL) and study the role of TRAIL in UVA-induced apoptosis of HaCaT cells as well as the influence of Polypeptide from Chlamys farreri(PCF)on TRAIL apoptotic pathway induced by UVA.Methods Cells were divided into five groups: control group, UVA model group,UVA+5.69 mmol?L-1 PCF group, UVA+2.84 mmol?L-1 PCF group, UVA+1.42 mmol?L-1 PCF group.Expression level of TRAIL mRNA was assayed by Real-Time PCR.Western blot analysis was used to determine the protein level of TRAIL and caspase-8 activation. The effect of TRAIL neutralization antibody on UVA-induced apoptosis was also investigated.Results TRAIL mRNA and protein levels increased after 8 J?cm-2 UVA radiation and the discrepancy was significant compared with control group(P