Clinical outcomes and cardiac safety of continuous antiHer2 therapy in c-erbB2-positive metastatic breast cancer patients.

Background: To explore clinical outcomes and cardiac safety of continuous antiHer2 therapy.

Patients And Methods: This retrospective study evaluates overall survival (OS), time to treatment failure (TTF), and cardiac safety of 80 consecutive Her2-positive metastatic breast cancer (MBC) patients that received ≥ 12 months of therapy with trastuzumab, followed by lapatinib-based or trastuzumab-based therapy.

Results: All patients received trastuzumab as first antiHer2 therapy; 54% received lapatinib in the second or subsequent line. Median OS was 34 months (12-120 months). Median OS was 48 months in the subgroup of 43 patients who received lapatinib and 26 months in the 37 patients who did not. Median TTF was shorter for lapatinib. There were three cardiac events and trastuzumab-based chemotherapy (CT) was interrupted in one patient because left ventricular ejection fraction (LVEF) decreased to ≤ 40%.

Conclusion: Continuous antiHer2 therapy provides good clinical outcomes, especially in those patients who received lapatinib. Cardiac dysfunction was a rare event, reversible, associated to trastuzumab and not related to treatment duration.