Left ventricular function following adjuvant chemotherapy for breast cancer: The NCIC CTG MA5 experience

Abstract

522 Background: Cardiac toxicity associated with anthracylines and more recently herceptin used in adjuvant breast cancer treatment is well recognized. Little is known about long term cardiac function as measured by left ventricular ejection fraction (LVEF) in patients post therapy. We analyzed the database of a randomized Phase 3 NCIC CTG study to assess changes over time in LVEF. Methods: Between 1989–1993, 710 pre/perimenopausal patients with node positive breast cancer were allocated to receive CEF (cyclophosphamide (C) 75 mg/m2 po d 1–14, epirubicin (E) 60 mg/m2 IV and fluorouracil (F) 500mg/m2 IV d1,d8) or CMF (C 100mg/m2 po d1–14, methotrexate (M) 40mg/m2 and F 600mg/m2 IV d1,8) given every 28 days for 6 cycles. The 10 year relapse-free survival was 52% (CEF) vs 45% (CMF), HR 1.31; stratified log rank, P=.007 (JCO, 2005,23;5166). LVEF was measured on both arms at baseline, months 6, 12, 36, and 60. Results: Compliance was good with measurements available on 100% of women at baseline, and 39% and 40% of patients at 60 months on the CEF and CMF arms respectively. Changes in LVEF from baseline are shown in the table . Conclusion: Changes in cardiac function as measured by a decrease in LVEF are not infrequent in patients after adjuvant therapy, even in the absence of anthracyclines. At 60 months, decreases of >10% were seen in up to 25% of patients receiving epirubicin administered at a cumulative dose of 720mg/m2 and in up to 10% of patients receiving CMF on whom measurements were available. The clinical significance of these findings needs to be assessed. Acknowledgements: This study was supported by funding from the Canadian Cancer Society through the National Cancer Institute of Canada and Pfizer Inc. [Table: see text] [Table: see text]