Cardiac Damage Risk in Radiotherapy of Esophageal Cancer: The Importance of Baseline Cardiac Risk Profile

Abstract

Background: The radiotherapy techniques are evolving. Besides optimal tumor coverage, considering organs at risk (OAR) is pertinent to radiation oncologists. In esophageal cancer radiotherapy, heart is the main OAR. Studies on excess absolute risk (EAR) of cardiovascular disease (CVD) in esophageal cancer radiotherapy are limited in the main literature. Therefore, this study was conducted to estimate the EAR of CVD in patients with esophageal cancer treated with the IMRT technique. Materials and Methods: Seventeen patients with esophageal cancer were selected. The patients were planned for the IMRT technique, and the 10-year EAR of CVD was estimated using the linear model. The data of major CVD risk factors [including age, smoking, and family history of heart attack, systolic blood pressure, total and HDL cholesterol, and high sensitivity c-reactive protein (hsCRP)] were obtained and the baseline risk of CVD was categorized into low- and high-risk groups using the Reynolds risk score. Results: Family history of heart disease and smoking increased the EAR of CVD significantly compared to the cholesterol and hsCRP. 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 esophageal cancer radiotherapy with the IMRT technique.