Cardiovascular risk profile of breast cancer patients treated with anthracycline-taxane containing adjuvant chemotherapy and/or trastuzumab

Abstract

666 Background: With improving longevity, post-treatment cardiovascular disorders will become an increasingly important indicator of competing mortality in early-stage breast cancer. As such, we conducted a pilot study to comprehensively evaluate the CVD profile of a subset of early-stage breast cancer patients treated with adjuvant taxane-anthracycline containing chemotherapy and/or trastuzumab. Methods: Twenty-six breast cancer patients (mean 20 months post chemotherapy) who participated in Breast Cancer International Research Group 006 clinical trial and 10 healthy age-matched women were studied. We measured 14 metabolic and vascular established CVD risk factors, BMI, VO2peak and left ventricular systolic function. All assessments were performed within a 14-day period. Results: Cardiac abnormalities were suggested by LVEF <50% in 10% of patients, LVEF remained >10% below pre-treatment values in 38% while 50% presented with resting sinus tachycardia. BNP was significantly elevated in 40% and was correlated with LVEF (r = -0.72, p=<.001). For the majority of CVD risk factors, similar proportions of patients and controls (35% to 60%) were classified as ‘undesirable.’ A significantly higher proportion of patients were classified with low VO2peak (46% vs. 0%, p<0.01), being overweight/obese (72% vs. 50%, p<0.05), and having resting sinus tachycardia (50% vs. 0%, p<0.01) compared with controls. VO2peak and BMI were correlated with CV risk factors (r = -0.64 to 0.63, p<0.05; r = -0.63 to 0.67, p<0.05, respectively). Exploratory analyses revealed several differences between CVD risk factors based on chemotherapy regimen. Conclusions: Breast cancer survivors treated with adjuvant chemotherapy are at a higher risk of developing late-occurring CVD than age matched controls due to direct and indirect treatment-related toxicity. No significant financial relationships to disclose.