Abstract 222P
Background
Trastuzumab improves survival outcomes in patients with HER2+ early breast cancer. However, cardiac toxicity is a concern in older patients particularly in the context of comorbidities. In this group, the rate of cardiac toxicity is unclear outside of clinical trials where older patients are under-represented. We evaluated the rates of cardiac events in a real-world population of patients treated at our Institution.
Methods
Data from 1,112 patients receiving trastuzumab in 2012-2018 were reviewed. Demographics, patient and tumour characteristics, comorbidities, treatments, cardiac assessments, adverse events and their management were recorded. Fisher’s exact test, chi-squared and Cox regression were used as appropriate.
Results
931 patients receiving curative trastuzumab and with complete data on cardiac monitoring were included in the analysis. Median age was 54 years (range 24-83) and Charlson comorbidity score 2 (range 0-8), with 195 patients (20.9%) aged 65+. 228 (24.5%) had a history of smoking and 385 (41.3%) of alcohol consumption. ECOG PS was 0-1 in 928 (99.7%) and 504 (54.1%) were postmenopausal. 713 patients (76.6%) had stage II-III disease and 638 (68.5%) ER+. Anthracyclines were given in 608 patients (65.3%) and radiotherapy in 689 (74.0%). The median number of trastuzumab doses was 18 (range 1-18). Based on the HFA-ICOS cardiovascular risk assessment tool, this was low in 400 patients (43.0%), medium in 449 (48.2%), high in 75 (8.1%) and very high in 7 (0.7%). More patients aged 65+ vs younger had medium and high cardiovascular risk (68.7% vs 42.8% and 28.2% vs 2.7%, both p=0.0001). There were no statistically significant differences in cardiac events (including asymptomatic LVEF decline >10% or below 50%, symptomatic heart failure, treatment discontinuation) between the two groups. No cardiac deaths were reported.
Conclusions
The overall cardiac safety of trastuzumab did not differ in older patients with early HER2+ breast cancer compared with their younger counterparts.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.