Baseline cardiac risk profile determines radiation-induced cardiac toxicity in patients with mid-lower esophageal cancer

Abstract Background: The radiotherapy techniques are evolving. Besides optimal tumour coverage, considering organs at risk (OAR) is pertinent to radiation oncologists. In mid-lower esophageal cancer (MLEC) radiotherapy, heart is the main OAR. Studies on excess absolute risk (EAR) of cardiovascular disease (CVD) in MLEC radiotherapy are limited in the main literature. Therefore, this study was conducted to estimate the EAR of CVD in patients with MLEC treated with the intensity-modulated radiation therapy (IMRT) technique. Results: Family history of heart disease and smoking increased the EAR of CVD significantly compared to the cholesterol and high-sensitivity C-reactive protein. The 10-year EAR of the high-risk group was more than four times of the low-risk group at all ages. In the low-risk group, EAR of CVD after radiotherapy of esophageal cancer can increase by up to 9·1%, while in the high-risk group, EAR increased by 34·89%. Conclusions: Adding the baseline CVD risk factors improved the estimation of EAR of heart disease after MLEC radiotherapy with the IMRT technique.