Abstract 12697: Identifying Patients at Low Risk for Cancer Therapy Related Cardiac Dysfunction in Patients Treated With Trastuzumab for HER 2+ Breast Cancer

Abstract

Introduction: Frequent monitoring every 3 months for Cancer Therapy-Related Cardiac Dysfunction (CTRCD) is recommended in patients who receive trastuzumab (tras) for cancer therapy. Aims: We examined the frequency and predictors of asymptomatic and symptomatic CTCRD in a contemporary cohort of patients with breast cancer treated with tras with or without anthracyclines (AC). Methods: Breast cancer patients who received tras with/without AC and had at least one baseline and one follow-up echocardiogram (echo) performed at our tertiary cancer center (2013-2022) were included. CTCRD was defined as left ventricular ejection fraction (LVEF) decline (Simpson’s bi-plane quantitative assessment) of at least 10% to < 50%. Risk factors for CTCRD were examined using univariable and multivariable Fine-Gray models. Results: The cohort included 502 patients with mean ± SD age 52.1±13.2 years, mean baseline LVEF 61.2±4.1%, and a median follow-up of 52.6 months. Patients had a mean of 5.5 ± 2.7 echocardiograms; 25 patients (5%) had CTCRD as defined above during follow-up, 3.4% (95% CI, 1.8-5.9) in the Tras only and 8.7% (95% CI, 4.7-14.5) in Tras + AC group. Only 8 patients (1.6%) developed new clinical HF at any time during follow-up, 6 of whom were associated with a concomitant decline in LVEF. Increasing age (HR, 95% CI, 1.03 1.01-1.06), baseline LVEF <55% (HR 7.3, 2.9-18.2), history of HF (HR 6.2, 1.5-25.2) and AC therapy (HR 4.5, 1.8-11.4) were independently associated with CTCRD. On follow-up, 1.1% of Tras-only vs 2.7% of Tras + AC group had a persistently decreased LVEF. In a low-risk group without any of the risk factors for CTCRD, only 1 % of patients had CTCRD without clinical HF. Conclusions: The incidence of asymptomatic and symptomatic CTCRD was low in patients receiving tras only. Patients without any risk factors receiving tras only could be considered for less frequent monitoring of asymptomatic CTCRD.