Abstract P3-14-07: Early detection of chemotherapy-induced cardiotoxicity in breast cancer patients

BACKGROUND

The incidence of cardiotoxicity in patients receiving treatment for breast cancer is unknown. There is not enough evidence about early detection and appropriate management of cardiotoxicity. The aim of this study is to identify early markers of risk of cardiac toxicity.

MATERIAL AND METHOD

Prospective study was conducted between 2014 and 2017 based on a cohort of 97 patients diagnosed with breast cancer treated with chemotherapy. Analytical biomarkers (natriuretic peptide, ultra-sensitive T troponin), echocardiogram parameters (left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS)) and electrocardiogram were performed. Analytical biomarkers were measured each chemotherapy cycle and cardiology test were performed before starting chemotherapy, 3 months afterwards, and then every six months during 5 years.

Cardiotoxicity was defined as a reduction in basal LVEF >10% with LVEF<55% in asymptomatic patients or >5% with LVEF<55% in symptomatic patients.

RESULTS

Patients characteristics are shown in table 1

Patients characteristicsVariablesNo cardiotoxicity (n=88)Cardiotoxicity (n=12)Gender (women/men)88/012/0Median age (range)53 years (29-79)47 years (37-70)Smoker (former smoker)13 (3)2 (2)Arterial hypertension202Dyslipemia160Diabetes62Previous chemotherapy11Prior mediastinal radiation therapy01

. All patients had the basal LVEF in normal range. Median follow-up was 26.5 months (13,5-39,6 months). A total of 10.3% had cardiotoxicity with reduction in basal LVEF >10% with LVEF<55% being asymptomatic and 2.1% were symptomatic. Five of these patients were treated with heart failure therapy: 5 with ACE (angiotensin converting enzyme) inhibitors and 3 with beta- blockers. Two of those (40%) who received specific treatment recovered basal LVEF-levels, 2 maintained LVEF dysfunction, and 1 died during follow-up due to tumor-related causes. In 83.3% of patients, cardiotoxicity occurred within the first year of follow-up.

In 50 patients SLG was calculated, in 30% it was lower than -12% in some measurement phase. In 5 cases the LVEF fell below 55% and the LRP decreased by 12% coincided.

The others patients, although they did not develop cardiotoxicity according to the established criteria, a decrease of the LVEF is observed during the treatment and in the first control, between 3-7%, which subsequently tends to recover spontaneously.

miRNA 21-5p, miRNA-133b, miRNA 210-3p, miRNA 423-5p, and miRNA-663b were analyzed. A model has been evaluated where a correlation between the levels of miRNA-133b, miRNA-21-5p and miRNA-210-3p and the decrease of LVEF in relation to treatment was observed.

CONCLUSIONS

Control by echocardiography and serum markers allowed us to detect early cardiotoxicity events and provide us an opportunity to start heart failure therapy on time with the aim of improving the control and evolution of it.Levels of miR-133b, miR-21-5p and miR-210 may alert for a risk of cardiotoxicity and can help to make decisions about treatments.

Acknowledgements: Project funded by European Comission (Hecatos FP7-HEALTH-2013-INNOVATION-1. Reference: CP-IP 602156-1) and RETICS program (RD12/0019/0025) cofunded by FEDER "una manera de hacer Europa”.

Citation Format: Salvador-Coloma C, Hernándiz A, Tejedor S, Miró V, Palomar L, Salvador A, Sepúlveda P, Santaballa A. Early detection of chemotherapy-induced cardiotoxicity in breast cancer patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-14-07.

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