In recent studies, elevated NT-proBNP level is a sensitive marker for subclinical cardiac disfunction after chemotherapy, but the issue is controversial.Aim
To evaluate the use of NT-proBNP as a predictor of anthracycline-induced cardiotoxicity.Aim
Method: We prospectively analysed 22 patients with stage II right breast cancer treated with epirubicin-containing adjuvant regimens. All patients were followed-up by a mixed team, oncologist and cardiologist, for 1 year. Patients received an average number of 5.18 ± 0.21 cycles of chemotherapy (epirubicin 100mg/m2, cyclophosphamide 500mg/m2, ± 5-fluorouracil 500mg/m2). All patients included in the study had normal ecocardiographic findings and NT-proBNP levels at baseline, and no previous evidence of cardiac disease. Patients underwent serial ecocardiographies and serum NT-proBNP measurements after a mean cumulative dose of 341.8 ± 28.06mg of epirubicin (2 cycles), at the end of anthracycline treatment (mean cumulative dose of 888.2 ± 41.49mg), 6 months and 1 year after the end of chemotherapy.Results
Mean age of studied patients was 51.05 ± 8,56 years. After 2 cicles of chemotherapy NT-proBNP level was increased in 12 patients (54.54%), at the end of treatment in 13 patients (59.09%), and after 1 year in 14 patients (63.63%), showing that there was no significant increase in the number of patients with elevated NT-proBNP levels throughout 1 year, comparing with the onset of treatment (P=0.7819). All patients who expressed high NT-proBNP levels at the onset of the treatment maintained it throughout the entire follow-up period. Subclinical cardiotoxicity, expresed by diastolic dysfunction, occured after a mean period of 10.20 ± 1.13 months in 10 patients (45,45%), all of them with abnormal NT-proBNP levels. There was a high significant correlation between diastolic dysfunction and high NT-proBNP levels (r=0,5997, P=0,0334, R2=0,3597). 2 patients (9,09%) experienced overt cardiotoxicity (clinical signs of heart failure, with systolic dysfunction). No signs of diastolic/systolic dysfunction were found among patients with normal NT-proBNP.Conclusion
In our study high level of NT-proBNP, early after onset of anthracycline treatment, was a sensitive predictor of subclinical anthracycline-induced cardiotoxicity.