Abstract P3-15-08: The Impact of Herceptin (Trastuzumab) on Cardiac Function in Adjuvant Early Breast Cancer Treatment-Norfolk and Norwich University Hospital Experience
Authors: Bowzyk A , Epurescu D 
Published: April 2011

Background: Adjuvant Herceptin in addition to chemotherapy improves clinical outcome in patients with high risk Her-2 positive breast cancer and this has become the standard of breast cancer care world-wide. However, it is well known that adjuvant Herceptin has been associated with reversible cardiac toxicity particularly after anthracyclines based chemotherapy regimens.

Objectives: To quantify retrospectively the incidence of asymptomatic and symptomatic decline in LVEF (Left Ventricular Ejection Fraction) in early breast cancer patients who received adjuvant Herceptin post-chemotherapy and radiotherapy if latter was indicated.

Methods: We reviewed the electronic notes of 38 patients who received adjuvant Herceptin therapy between January 2007 and January 2008. Patients’ characteristics: Age range 25-71 years (Median 49); Tumour size ≥1 cm 36 patients (95%) ; &lt;1 cm 2 patients (5%). Nodal status-0 Lymph Nodes (LN) 12 patients (32%); 1-3 positive LN 14 (36%); More than 4 positive LN 12 (32%). Hormone Receptor Status: 13/38 (34%) were ER (+) and 25/38 (66%) were ER (-) Cardiac assessment and monitoring were assessed as per local guidelines.

Results: In our cohort of 38 female patients with early breast cancer 18 cycles of adjuvant Herceptin were planned to be given post-chemo and radiotherapy. In 1 patient Herceptin was stopped after 5 cycles as in-house FISH audit showed HER-2 negative. In 6 patients (15%) Herceptin was stopped due to reduction in LVEF ≥10% as 4 (10%) were asymptomatic and 2 symptomatic (5%). Anthracyclines based regimens were given to 37 patients (97%) and only 1(3%) had anthracycline/taxane combination. Out of 38 only 1 patient (3%) had dyslipidaemia. All patients had a LVEF ≥55% on baseline Echocardiogram. Herceptin was given sequentially after chemotherapy and radiotherapy in all patients (range 4-24 weeks). There was no significant change in LVEF post chemo/radiotherapy and pre Herceptin. In the 2 symptomatic patients Herceptin was discontinued after 10 and 14 cycles. In 1 patient LVEF recovered fully after aortic valve replacement, the other patient required treatment. In the 4 asymptomatic patients Herceptin was discontinued after 5, 9(2) and 13 cycles. In 1 patient Herceptin was reintroduced when LVEF recovered but discontinued afterwards as LVEF became impaired again. The 3 out of 4 asymptomatic patients did not require treatment although their LVEF value remained lower than the baseline and in one patient on follow-up LVEF subsequently deteriorated requiring cardiac treatment.

Discussion: In our cohort of 38 patients 5% developed symptomatic and 10% asymptomatic decline of ≥10% in LVEF requiring premature discontinuation of adjuvant Herceptin. This is higher than data from adjuvant Herceptin trials (HERA 1.7% symptomatic and 7% asymptomatic reduction in LVEF). Almost all patients 37(97%) received adjuvant anthracycline treatment prior to Herceptin and such exposure could be a contributory factor to our findings. The risk factors for cardiac disease were negligible (3%) and all patients had a normal LVEF on Echocardiogram prior to Herceptin treatment.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-15-08.