Effects of anthracycline, cyclophosphamide and taxane chemotherapy on QTc measurements in patients with breast cancer

• Published in: PloS one Vol. 13; no. 5; p. e0196763
• Main Authors: Veronese, Pedro, Hachul, Denise Tessariol, Scanavacca, Mauricio Ibrahim, Hajjar, Ludhmila Abrahão, Wu, Tan Chen, Sacilotto, Luciana, Veronese, Carolina, Darrieux, Francisco Carlos da Costa
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 03.05.2018; Public Library of Science (PLoS)
• Subjects: Anthracycline; Biology and Life Sciences; Biomarkers; Brain natriuretic peptide; Breast cancer; Calcium-binding protein; Cancer; Cancer therapies; Cardiac arrhythmia; Cardiotoxicity; Cardiovascular diseases; Chemotherapy; Complications and side effects; Cyclophosphamide; Diagnosis; Dispersion; Doxorubicin; Drug therapy; EKG; Electrocardiography; Health aspects; Heart failure; Lymphoma; Medicine and Health Sciences; Metastases; Oncology; Patients; Prolongation; Research and Analysis Methods; Risk factors; Supervision; Taxanes; Troponin; Brazil
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0196763

Acute and subacute cardiotoxicity are characterized by prolongation of the corrected QT interval (QTc) and other measures derived from the QTc interval, such as QTc dispersion (QTdc) and transmural dispersion of repolarization (DTpTe). Although anthracyclines prolong the QTc interval, it is unclear whether breast cancer patients who undergo the ACT chemotherapy regimen of anthracycline (doxorubicin: A), cyclophosphamide (C) and taxane (T) may present with QTc, QTdc and DTpTe prolongation. Twenty-three consecutive patients with breast cancer were followed prospectively during ACT chemotherapy and were analyzed according to their QT measurements. QTc, QTdc and DTpTe measurements were determined by a 12-lead electrocardiogram (EKG) prior to chemotherapy (baseline), immediately after the first phase of anthracycline and cyclophosphamide (AC) treatment, and immediately after T treatment. Serum troponin and B-type natriuretic peptide (BNP) levels were also measured. Compared to baseline values, the QTc interval was significantly prolonged after the AC phase (439.7 ± 33.2 ms vs. 472.5 ± 36.3 ms, p = 0.001) and after T treatment (439.7 ± 33.2 ms vs. 467.9 ± 42.6 ms, p < 0.001). Troponin levels were elevated after the AC phase (23.0 pg/mL [min-max: 6.0-85.0] vs. 6.0 pg/mL [min-max: 6.0-22.0], p < 0.001) and after T treatment (25.0 pg/mL [min-max: 6.0-80.0] vs. 6.0 pg/mL [min-max: 6.0-22.0], p < 0.001) compared to baseline values. In this prospective study of patients with non-metastatic breast cancer who underwent ACT chemotherapy, significant QTc prolongation and an elevation in serum troponin levels were observed.