HERCEPTIN administration can result in the development of ventricular dysfunction and congestive heart failure. Left ventricular function should be evaluated in all patients prior to and during treatment with HERCEPTIN. Discontinuation of HERCEPTIN treatment should be strongly considered in patients who develop a clinically significant decrease in left ventricular function. The incidence and severity of cardiac dysfunction was particularly high in patients who received HERCEPTIN in combination with anthracyclines and cyclophosphamide. (Please see full Prescribing Information, including Boxed WARNING.)

	Breast cancer is the most common malignancy among women in the United States, with 211,300 new cases projected for 2003.[4]
	Amplification of the Human Epidermal growth factor Receptor 2 (HER2) gene results in HER2 protein overexpression. HER2 overexpression occurs in approximately 25% of breast cancer patients.[5]
	HER2 protein overexpression correlates with several negative prognostic variables, including estrogen receptor-negative status, high S-phase fraction, positive nodal status, mutated p53, and high nuclear grade.[6]
	HER2 gene amplification was found to be highly correlated with shortened disease-free survival and shortened overall survival of node-positive patients.[5]

Herceptin is FDA approved for first-line use in combination with paclitaxel for the treatment of HER2 protein overexpressing metastatic breast cancer in patients who have not received chemotherapy for their metastatic disease. Herceptin as a single agent is indicated for the treatment of HER2 protein overexpressing metastatic breast cancer in patients who have received one or more chemotherapy regimens for their metastatic disease.[1]