Analysis Of Dose Difference And Influencing Factors Of X-ray And Electronic Ray Supplement In Tumor Bed After Breast Conserving Surgery

Objective:Study to compare the early postoperative X-ray of patients with breast cancer confirmed breast augmentation tumor bed synchronous integrated intensity modulated radiation therapy（imrt）filling quantity after the process with the electronic line tumor bed synchronous dosimetry characteristics of intensity modulated radiation therapy（imrt）filling amount,to explore different ways of filling quantity of whole milk heart,lungs and spinal cord by mammary gland volume group according to the influence of the dosage and compare BMI under whole milk target organ threatening dosimetry characteristics methods:From October 2019 to August 2021,40 patients with early breast cancer underwent radiotherapy after breast-conserving surgery in the Department of Radiotherapy of the Second Hospital of Jilin University were selected,including 18 patients with left breast cancer and 22 patients with right breast cancer The X-ray tumor bed synchronous integrated intensity modulated radiotherapy plan and electronic line tumor bed synchronous intensity modulated radiotherapy plan were all performed.Relevant dosiological data were collected and statistical analysis was performed using SPSS（25.0）software.The dosiological characteristics of tumor bed target area of whole breast and dose difference of organs at risk were compared under the two treatment plans.Dosimetric characteristics of organs at risk in whole breast target area under breast volume grouping Results:1)Dosimetry comparison between X-ray tumor bed synchronous im RT and electronic tumor bed synchronous im RT of whole milk target: there were statistically significant differences in Dmax,Dmean,V105,V110,D5,D95 and HI of whole milk target（P<0.05）.2)Dosimetry comparison of tumor bed target area between X-ray synchronous im RT and electronic line synchronous im RT: tumor bed target area Dmax Dmean Dmin V95 V105 V110 D5 D95 tumor bed target area conformal index and uniformity index were statistically significant between the two groups（P<0.05）3)Dosimetry comparison of THE OAR（lung,heart and spinal cord）of organs at risk in X-ray tumor bed synchronous im RT and electronic tumor bed synchronous im RT: there were statistically significant differences between the V20 and V30 of the affected lung（P<0.05）;Heart Dmean of right breast cancer patients was statistically significant（P<0.05）.4)Comparison of dosimetry between X-ray tumor bed synchronous im RT and electronic line tumor bed synchronous im RT in the target area of whole breast in BMI≥25 groups: There were statistically significant differences in Dmax,Dmean,V105,V110 and D5 of whole milk target area（P<0.05）.Comparison of dosimetry of whole breast target area between X-ray tumor bed synchronous im RT and electronic line tumor bed synchronous im RT in BMI < 25 groups: Dmean,V105,V110,D5 and D95 in whole breast target area were statistically significant（P<0.05）.5)Dosimetry comparison between X-ray tumor bed synchronous im RT and electronic line tumor bed synchronous im RT and organs at risk（OAR）in BMI≥25group: there was no statistical significance in all parameters between the two groups（P>0.05）.Comparison of dosimetry of ORGANS at risk（OAR）with X-ray tumor bed synchronous im RT and electronic line tumor bed synchronous IMRT in BMI < 25groups: V20,V30 and Dmean of affected lung,Dmean of healthy lung,Dmean of heart and Dmean of spinal cord had statistical significance（P<0.05）.6)Dosimetry comparison of whole breast target area with BMI≥25 and BMI < 25 in X-ray tumor bed synchronous complementary im RT group: Dmean,V95 and V105 in whole breast target area were statistically significant（P<0.05）.Dosimetry comparison of BMI≥25 and BMI < 25 OAR between X-ray tumor bed im RT groups:V5 and V30 in affected lung and Dmean in spinal cord were statistically significant（P<0.05）.7)Dosimetry of the whole breast target area with BMI≥25 and BMI < 25 between the electronic line tumor bed synchronous supplement groups: there were statistically significant differences between V95 and V105（P<0.05）.Dosimetry comparison of BMI≥25 and BMI < 25 OAR between the electronic line tumor bed synchronous supplement groups: the difference of spinal Dmean between the two groups was statistically significant（P<0.05）.8)The V5,V20,V30,Dmean of affected lung,Dmean of healthy lung and Dmean of spinal cord in small breast group were significantly lower than those in medium breast group and large breast group,and the differences were statistically significant（P<0.05）.V10 and whole lung V20 were significantly lower than those of medium-breast group and large-breast group,but there was no statistical significance between them（P>0.05）.The V5,V15 and Dmean of small breast and medium breast groups were significantly lower than those of large breast group,and the differences were statistically significant（P<0.05）.9)Lung V5,V20,V30,lung Dmean and spinal Dmean in the small breast group were significantly lower than those in the large breast group,with statistical significance（P<0.05）.The Dmean of healthy lung was significantly lower than that of medium breast group and large breast group,and the difference was not statistically significant（P>0.05）.The V5,V15 and Dmean of small breast and medium breast groups were significantly lower than those of large breast group,and the differences were statistically significant（P<0.05）.10)Si B-IMRT technology was superior to electronic line tumor bed supplement in improving the uniformity of dose distribution in the whole breast target area in the small breast group and the medium breast group,and the difference was statistically significant（P<0.05）.There was no significant difference in the uniformity of dose distribution in the whole breast target area in the large breast group under the two plans.11)The changes of breast volume and radiotherapy technology had no statistical significance on CI（P>0.05）.Conclusion:1.Under the premise of meeting the coverage of planned target area,si B-IMRT technology is significantly better than electronic line tumor bed synchronous supplement in improving the dose distribution uniformity and suitability of the whole breast boot area and tumor bed target area.2.Sib-imrt is superior to electronic line tumor bed synchronous supplement in protecting organs at risk（heart,lung and spinal cord）.3.The Dmean,V105,V110 and D5 of the whole breast target area were better than the synchronous supplement of electronic line tumor bed in both underweight/normal and overweight/obesity patients.4.Under the two treatment plans,the V5,V20,V30,Dmean of the lung and spinal cord in the small breast group were significantly lower than those in the large breast group,while the V5,V15 and Dmean of the heart in the small breast and medium breast groups were significantly lower than those in the large breast group.5.There was no statistical significance in the influence of breast volume on CI and HI.Technical changes in breast volume had a statistically significant effect on HI,but not on CI.