Prospective analysis of cardiovascular complications in HER2-positive breast cancer patients treated with anthracycline-free regimens.

Abstract

e12545 Background: The assessment of cardiovascular complications (CVC) frequency and the predictive role of the HFA-ICOS scale is needed for pts with HER2-positive breast cancer (BC) receiving anthracycline-free therapy. Methods: 2,592 consecutive BC pts were prescreened to enroll 188 newly diagnosed stage I-III HER2-positive BC women (mean age 56 yrs) before start of HER2-inhibitors. Routine examination was added with cardiac biomarkers and speckle-tracking echocardiography every 3 month during 1 year and 3 months after the end of treatment. Anthracyclines were used 12 pts (6%). Results: The median follow-up was 7.8 months (ongoing). Cardiovascular comorbidities included arterial hypertension (AH) - 77 (41%), dyslipidemia - 140 (74%), obesity - 56 (30%), diabetes - 20 (10%), chronic kidney disease - 29 (15%), coronary artery disease - 5 (3%), atrial fibrillation - 9 (5%), chronic heart failure (HF) - 7 (4%), past ischemic stroke - 6 (3%), past myocardial infarction - 4 (2%) pts. The overall incidence of at least one CVC during antiHER2-therapy was 28%, including destabilization of AH — 15 (8%); newly diagnosed AH — 9 (5%); decrease in left ventricular global longitudinal strain > 15% from baseline — 19 (10%); asymptomatic decline in left ventricular (LV) ejection fraction (EF) < 50% — 5 (3%); new elevation of NT-proBNP level — 19 (10%); asymptomatic elevation of troponin level — 6 (3%); moderate hydropericardium — 5 (3%); deep vein thrombosis — 6 (3%); superficial vein thrombosis — 5 (3%); pulmonary embolism — 1 (0.5%); ischemic stroke — 1 (0.5%); symptomatic HF with LVEF decline < 40% — 1 (0.5%). Therapy was interrupted due to CVC in only two pts (ischemic stroke and symptomatic HF). In the multivariate analysis increased LV mass index was an independent risk factor for CVC (aOR = 1.022 per 1 g/m²; p = 0.017). By the HFA-ICOS scale, 160 (85%) pts were categorized as low/moderate risk and 28 (15%) as high/very high risk. Risk stratification by the HFA-ICOS scale showed no statistically significant prognostic value for overall CVC: frequency was 39% in the high/very high-risk group vs 26% in the low/moderate-risk group (p = 0.169). However, for the specific endpoint of cancer therapy-related cardiac dysfunction (CTRTD), the HFA-ICOS scale showed a statistically significant but clinically modest association (OR = 2.39, 95% CI 1.002–5.70, p = 0.045). The weak effect size (Phi = 0.147) suggests limited discriminatory power for CTRTD prediction in this cohort. Conclusions: CVC occur in 28% of HER2-positive BC on anthracycline-free therapy, AH was most frequent CVC. Prevalence of severe adverse events was 1,5% highlighting the overall controllability of most complications and supporting the manageable safety profile of trastuzumab-based regimens under active monitoring. The HFA-ICOS scale showed endpoint-specific utility for CTRTD, but limited value for overall CVC prediction.