Abstract Abstract Cardiotoxicity is an adverse effect of treatments for breast cancer, particularly anthracyclines and trastuzumab, which is an antagonist of the human epidermal growth factor receptor 2 (HER-2). Consensus definitions of cardiotoxicity typically involve a reduction LVEF of more than 10 percentage points to a value below the normal range or overt heart failure symptoms. Current guidelines recommend echocardiographic evaluation before starting trastuzumab and every 3 months during treatment. However, this strategy is demanding, and its efficiency in low-risk individuals remains unproven. Purpose: This study aimed to evaluate the predictive capability of clinical and echocardiographic variables, assessed at the first assessment after initiating trastuzumab treatment, to foresee treatment suspension due to cardiotoxicity in the first 12 months. Methods Pts with HER-2 positive breast cancer undergoing trastuzumab treatment were included. Clinical and echocardiographic parameters were evaluated at baseline and an average of 4 months after initiation of treatment. Data were compared between pts who had to stop treatment due to cardiotoxicity in the first 12 months and those who continued. Right ventricular systolic dysfunction was defined as TAPSE 17 mm or S’ velocity 9.5 cm/s. Data are presented as frequencies, medians, and interquartile ranges. The Mann-Whitney U test and Chi-square test were used for group comparison. Regression analysis and ROC curve analysis were performed to evaluate variable’s capacity to predict outcome. A p-value 0.05 was considered statistically significant. Results A total of 37 women with a mean age of 60.0 ± 13.0 years were included. Treatment was suspended in 4 (10.8%) due to significant cardiotoxicity, occurring 3-7 months after the initiation. There was a significant difference between the groups in LVEF at 4 months (42.0% vs. 63.0%, p=9,991), LVESV (28.5 vs. 16.0 mL/m2, p=0.002), and LVEDV (51.0 vs. 44.5 mL/m2, p=0.043). Logistic regression analysis revealed that these parameters alone were not predictive of treatment interruption (p=0.998). Despite this, ROC curve analysis indicated very good discriminatory ability of this parameters between the two groups. The AUC for LVEF was 0.996, with a Sn of 97% and Sp of 100% for a cut-off of 55.5%; for LVESV was 0.978, with a Sn of 100% and Sp of 79% for a cut-off of 21.5 mL/m2; and for LVEDV was 0.817, with a Sn of 75% and Sp of 79%) for a cut-off of 47.5 mL/m2. Although statistical significance was not found for other parameters (Table 1), we observed that women who had to suspend treatment were older, had lower baseline LVEF, and had larger cardiac chambers. Conclusion A combination of LVEF below 55.5%, an LVESV above 21.5 mL/m2, and an LVEDV above 47.5 mL/m2 should raise concern of potential subsequent cardiotoxicity. Further assessment is needed to determine whether the frequency of echocardiographic evaluations should be influenced by the first evaluation.
Almeida et al. (Fri,) studied this question.