Authors
- Martina Lovrić Benčić — University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0001-8446-6120
- Lada Bradić — University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0001-8296-699X
- Rea Levicki — University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0003-3687-1310
- Juraj Jug — University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0002-3189-1518
- Marta Begovac — University Hospital Centre Zagreb, Zagreb, Croatia
- Marina Mihajlović — University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0002-0027-9676
Keywords
trastuzumab, trastuzumab-emntansine, QTc interval, HER2+ breast cancer
DOI
https://doi.org/10.15836/ccar2018.466Full Text
Introduction : Trastuzumab and trastuzumab-emtansine are antibody drugs and antibody-conjugate for human epidermal growth factor receptor 2 (HER2)- positive breast cancer. Their possible side effects can be QT prolongation and reduction of left ventricular ejection fraction (LVEF), as previously documented. ( 1 - 3 ) Methods and Results : All patients were previously treated with standard regimen: paclitaxel and cisplatinum. After that they received specific antibody drugs. The aim of this study was to test their effect on QTc interval in our patients. A total of 26 patients with preserved LVEF were treated with trastuzumab and before every application, ECG was obtained and analyzed. Later on, 24 patients (aged 57.33 years; 46-69 years) continued the treatment with trastuzumab-emtansine because of metastatic disease. Due to reduction of LVEF two patients could not continue with therapy. The last ECG was obtained 6 months after the last drug application. Statistical analysis was performed using standard t-test. Significant QTc prolongation was noticed after the third application of both drugs, continued during the fourth, fifth and sixth application of both drugs and normalization was noticed after six months without therapy. Results are shown in tables 1 , 2 and 3 . Conclusion : Treatment with trastuzumab and also with trastuzumab-emtansine significantly prolonged QTc interval in patients with breast cancer, but the change was reversible after the cessation of treatment.