Effects Of Different Radiotherapy Doses On The Heart Of Middle And Mid-Lower Esophageal Squamous Cell Carcinoma

Objective:To analyze the differences between the low-dose radiotherapy group and the high-dose radiotherapy group in the subacute radiation-induced heart disease caused by radiation in locally advanced inoperable esophageal squamous cell carcinoma.Methods:A total of 55 patients with middle and lower esophageal squamous cell carcinoma were selected from Sichuan Provincial People’s Hospital from October 2015 to October 2020 for retrospective study.According to different treatment doses,they were divided into high dose group(28 patients,≥56Gy,1.8-2Gy)and low dose group(27 patients,<56Gy,1.8-2Gy).The number of valvular,pericardial,and myocardial lesions on echocardiography and the difference in dose-volume fraction between the two groups were compared.The results were analyzed by SPSS 23.0.0.Results:The mean values of EF in both groups were lower after radiotherapy than before,but there was no statistical significance(P>0.05).Comparing the mean EF of the two groups after radiotherapy,the mean EF of the high-dose group was slightly lower than that of the low-dose group,but there was no statistical significance between them(P>0.05).There were 14 cases of heart structural and functional lesions in the high-dose group and 11 cases in the low-dose group,and there was no statistical significance in the number of cases of valvular,pericardial and myocardial lesions between the two groups(P>0.05).In the comparison analysis of dose volume fraction of the two groups,V20,V30 and V40 of the heart injury group in the high dose group were higher than those in the non-injury group,and there was statistical significance(P<0.05).In low dose group,V30and V40 of heart injury group were higher than those of non-injury group(P<0.05).V30 and V40 in high dose injury group were higher than those in low dose injury group(P<0.05).Conclusion:There is no significant difference in the probability of subacute cardiac injury caused by high dose and low dose radiotherapy.V20,V30,V40%in the high dose group and V30,V40 in the low dose group can reflect and predict the occurrence of radiation heart injury,effective control of the corresponding dose volume parameters can prevent and reduce the occurrence of subacute radiation heart injury.The main difference between the two causes of RIHD lies in the difference between V30 and V40,which can guide us to further dose control.