Mehmet Cem BASEL, Aydın DURSUN, Kemal EKİCİ, Kerem Can YILMAZ
Eskisehir Medical Journal - 2026;7(3):279-284
Introduction: This study aimed to evaluate the effects of radiotherapy (RT) on electrocardiographic parameters, including QT, corrected QT (QTc), Tp-e interval, and Tp-e/QT and Tp-e/QTc ratios, in patients with breast and lung cancer. Methods: A total of 27 patients (15 with lung cancer and 12 with breast cancer) were included. The decision for RT was made by a multidisciplinary oncology board. Standard 12-lead electrocardiography (ECG) and transthoracic echocardiography were performed before and after RT. Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were calculated. The mean myocardial radiation dose ranged between 5.0 and 6.5 Gy. Cardiac radiation exposure was similar between groups. Results: There were no significant changes in blood pressure, heart rate, or left ventricular ejection fraction after RT. However, Tp-e interval and Tp-e/QT ratio were significantly prolonged following RT in both groups. In patients with lung cancer, the Tp-e interval increased from 72.94+/-7.32 ms to 80.20+/-5.87 ms. In patients with breast cancer, it increased from 65.41+/-4.02 ms to 73.00+/-2.64 ms. Conclusion: Radiotherapy may lead to early alterations in ventricular repolarization parameters. Tp-e interval and related indices may serve as early markers of radiotherapy-induced cardiac damage. Routine ECG monitoring may be beneficial in these patients.
