Background .– A well-known side effect of anthracycline’s chemotherapy is cardiotoxicity. It consists in developing a dose-dependent cardiomyopathy with an incidence ranging from 2 to 20%. Assessment of biohumoral markers may be useful in early detection of subjects at high risk of developing cardiotoxicity, as demonstrate by studies carried out in patients undergoing a high-dose chemotherapy. However, there are few studies considering both the measurement of natriuretic peptides and not-high-dose protocol of chemotherapy.

Aim .– The aim of the study was to evaluate the possibility of early detection of subjects at high-risk for developing left ventricular dysfunction in breast cancer patients undergoing non-high-dose chemotherapy (NHDC).

Methods and results .– In 71 patients treated with anthracycline NT-proBNP, CK-MB and cardiac Troponin I (cTnI) were evaluated before each drug administration and 24 hours after. Left ventricular dimension/function was assessed by echocardiography at baseline, every two cycles, at the end of chemotherapy, 3, 6 and 12 months during the follow-up. NT-proBNP, CK-MB and cTnI values were normal at baseline in all the patients. Throughout the chemotherapy, CK-MB were normal, cTnI was abnormal only occasionally in 4 patients, NT-proBNP showed abnormal values. According to these NT-proBNP modifications, the patients were divided into 2 groups: group A (50 patients), where normal values (23 cases) or temporary alterations (27 cases; i.e. increase at 24 hours and then decrease to normal values) were detected; group B (21 patients) with persistent NT-pro-BNP abnormalities throughout all the measurements. The Group B showed follow-up left ventricular impairment greater than the Group A. The percentage difference (baseline-peak) NT-proBNP was predictive for LV impairment at 3, 6 and 1-year follow-up; percentage difference (baseline-peak) NT-proBNP higher than 36% was predictive for LV impairment at the same follow-up interval times.

Conclusions .– Serial evaluation of NT-proBNP may be a useful tool in order to early detect the patients at high-risk of cardiotoxicity, among those treated with NHDC.