Background

Trastuzumab is recommended as adjuvant treatment by the National Institute for Health and Clinical Excellence (NICE) in women with Her-2 positive early breast cancer (EBC).

Method

Retrospective analysis of 106 women treated with adjuvant Trastuzumab from 2006-2009. We investigated Trastuzumab-related cardiac toxicity and also assessed adherence to NICE guidelines. Congestive heart failure (CHF) was classified according to the New York Heart Association(NYHA) classification and diagnosed independently by a cardiologist.

Results

All patients had baseline assessment of Left Ventricular Ejection Fraction (LVEF), mostly by MUGA scanning. All but 2 patients (98.11%) had a baseline LVEF of >55%. Trastuzumab was commenced in 2 patients who did not meet this criteria following advice from a cardiologist. However, treatment was suspended in both women within 3 months following development of NYHA grade 2 CHF due to precipitation of previously unidentified structural defects/arrhythmias. 1 patient with 3 cardiac risk factors but acceptable baseline LVEF developed NYHA grade 3 CHF following 6 months of treatment. 7/106 (6.6%) women had an asymptomatic drop in LVEF (>10% from baseline or LVEF<50%).Trastuzumab was discontinued in 6 women (5.66%). 100/106 (94.33%) women had previous (neo) adjuvant anthracycline based chemotherapy and none of them received in the presence of 2 or more cardiac risk factors. Age, left sided radiotherapy without cardiac shielding showed no increased risk. While on treatment, maximum LVEF (%) drop from baseline was higher in those with baseline LVEF<60%.

Conclusion

This study highlights the importance of adhering to NICE guidelines in reducing the incidence of Trastuzumab-related cardiac toxicity. Patients with a low baseline LVEF and/pre-existing cardiac anomalies/risk factors were more likely to experience cardiac toxicity.