Analysis of influencing factors for cardiac death after radiotherapy with or without chemotherapy for middle-or lower-thoracic esophageal cancer

Objective: To analyze the influencing factors for cardiac death (CD) after radical radiotherapy with or without chemotherapy in patients with middle-or lower-thoracic esophageal cancer. Methods: The clinical data of 140 patients who met the inclusion criteria were analyzed retrospectively, as well as the effect of cardiac dose-volume factors suggested by dose-volume histogram in the therapeutic regimen on CD. Chi-square test was applied for comparison of categorical data between groups, and independent-samples t-test was applied for comparison of continuous data between groups; logistic regression analysis was applied to analyze the association of cardiac dose-volume and clinical factors with CD. Results: A total of 103 patients died, including 8 patients with CD (7.8%). The univariate analysis of CD showed that age ≥ 70 years (P = 0.033), a history of diabetes (P = 0.043), lower-thoracic esophageal cancer (P = 0.017), and the length of esophageal lesions > 5 cm on esophagography (P = 0.013) were risk factors for CD, and heart D_mean(P = 0.032) and heart V₅₀(P = 0.045) were influencing factors. The results of ROC curve analysis showed that heart D_mean could effectively predict CD (P = 0.044), with a cut-off value of 3325 cGy. The results of multivariate logistic analysis showed that the length of esophageal lesions on esophagography (P = 0.013) and heart D_mean (P = 0.034) were independent prognostic factors for CD. Conclusions: The length of esophageal lesions on esophagography and heart D_mean were independent prognostic factors for CD, and the value of heart D_mean can effectively predict CD; therefore, it is suggested that the value of heart D_mean be controlled during the development of therapeutic regimens. (authors)