Risk of Heart Failure after Anthracycline (Adriamycin/Daunomycin) and Trastuzumab (Herceptin) Treatments for Breast Cancer

This study evaluated the risk of heart disease associated with two commonly prescribed treatments for breast cancer. The main finding was that Trastuzumab (Herceptin) and Anthracycline (Adriamycin/Daunomycin) treatments are associated with a higher risk of heart failure or ‘cardiomyopathy’.

Anthracyclines are very effective chemotherapeutic agents, usually prescribed to younger women. The age limitations are due to their potential to worsen or cause heart disease. Trastuzumab is a newer drug, used specifically for tumors with large amounts of a specific receptor: HER2. The presence of HER2 is determined by biopsy and laboratory analysis. Cardiomyopathy (CM) literally means “heart muscle disease”. This condition describes a gradual weakening of the heart muscle which diminishes the blood-pumping capacity. The end result of this process is heart failure (HF).

This study was performed based on data declared in the national cancer registry. Of the total 12,500 women eligible for the study, 5807 (46.5%) received no chemotherapy. Another 3697 women (29.6%) received anthracycline chemotherapy alone, 112 (0.9%) received Trastuzumab alone and 442 (3.5%) received anthracycline chemotherapy plus Trastuzumab. The remaining 2442 women (19.5%) received other forms of chemotherapy. The women who received anthracyclines were generally younger.

Risks of CM or HF were increased with all forms of therapy. The highest risk (7.19% incidence after 5 years) was observed in the anthracycline plus Trastuzumab group. Trastuzumab alone was riskier than anthracycline-only therapy. Anthracycline chemotherapy alone and other forms of chemotherapy were equivalent in terms of CM or HF risk.

These results suggest that the combination therapy, despite being effective, is also very risky.

Heart conditions should be monitored carefully and cancer treatment regimens adjusted if signs of CM or HF appear. The FDA issued a warning about Trastuzumab: FDA warning for Trastuzumab.

You should carefully discuss the risks of chemotherapy with your doctor.