Analysis Of Related Factors Of Short-term Cardiotoxicity In Different Radiotherapy Methods For Left Breast Cancer

Objective:Evaluation: 1.The dose difference between conventional electronic radiation therapy and intensity modulated radiation therapy(IMRT)after the modified radical treatment of left breast cancer;2.Effects of conventional electronic radiotherapy,IMRT and IMRT on cardiac toxicity after modified radical resection for left breast cancer.Methods: Ninety-six patients with radiation-treated radical mastectomy and breast-conserving surgery were enrolled in our hospital from December 2016 to September 2018 [male: female = 2:94,mean age 48.6 years].The stage is I~IIIA,including 17 in stage I,71 in stage II,and 8 in stage IIIA.All patients underwent CT-enhanced scanning localization before treatment.The treatment target area,the organ and heart and its substructure were delineated in the Philips Pinnacle3 V9.10 planning system.The treatment plan was designed to record the patient’s heart and its sub-radiation under different radiotherapy methods.Structural dose-togram(DVH)parameters.Twenty patients with modified left radical mastectomy were enrolled.The conventional electronic line and IMRT plan were designed to compare the doses.And within one week before radiotherapy to one week after radiotherapy: hypersensitive troponin I.One week before radiotherapy and one to three months after radiotherapy:echocardiography,electrocardiogram and myocardial perfusion imaging(MPI).Post-treatment cardiotoxicity was assessed using NCI-CTC version 2.0(National Cancer Institute General Toxicity Criteria).Data processing was performed using SPSS 20.0 software.The comparison between the two sample means was performed by t test.The comparison between the mean of multiple samples was analyzed by ANOVA.The results were expressed as mean ± standard deviation(x ± s).The testlevel α = 0.05,which was statistically significant when P < 0.05.Results: Dosimetry aspects: on the left side of the breast cancer modified radical surgery IMRT radiation dose distribution in target area uniformity index(HI),conformal index(CI)were superior to the conventional electron radiotherapy plan.In terms of cardiopulmonary tolerance,V5,V20 and Vmean of the left lung of IMRT plan were significantly higher than that of the electronic line plan,and the difference was statistically significant(P<0.05).Heart V40 and Dmean of IMRT plan were higher than that of electronic line plan,and the difference was statistically significant(P<0.05).There was no significant difference in cardiac V30(P>0.05).2.The cardiac toxicity aspects: on the left side of the breast cancer confirmed breast postoperative IMRT before and after radiotherapy in patients with left ventricular ejection fraction(1 eft ventricular ejection fraction,LVEF)difference was statistically significant(P < 0.05).The parameters related to the cardiac toxicity: heart D5,left ventricular D25,D35,left anterior descending coronary artery(left anterior item first-just coronary artery,LAD)on3dmax difference was statistically significant(P <0.05).The cardiotoxicity of the three treatment methods after modified radical resection of left breast cancer,including electron ray radiotherapy,IMRT and IMRT after breast consering was 1~2 degrees in a short period,and there was no statistically significant difference in the incidence of cardiotoxicity between the three methods(P>0.05).Conclusions: 1.In terms of HI and CI,IMRT after modified radical resection of left breast cancer is superior to conventional electronic radiotherapy,and in terms of cardiopulmonary dose,conventional electronic radiotherapy is superior to IMRT.2.Degree 1-2 cardiotoxicity may occur after left breast cancer postoperative radiotherapy.However,there was no difference in cardiotoxicity between IMRT,IMRT and IMRT after modified radical mastectomy for left breast cancer.