the study aims to evaluate the cardioprotective effect of atorvastatin in breast cancer female patients treated with doxorubicin based chemotherapy

female patients with newly diagnosed breast cancer, who are candidates for AC protocol will be recruited from Damanhour oncology center.

All enrolled patients will be randomly assigned into 2 arms:

• Control arm : will receive AC regimen only (doxorubicin 60 mg/m² IV + cyclophosphamide 600 mg/m² IV) for 4 cycles every 21 days.
• Atorvastatin arm : will receive AC regimen mentioned above + atorvastatin 40 mg orally once daily for 3 months.

All patients will be submitted to:

• Full patient history and clinical examination.
• Routine follow up before and after each chemotherapy cycle (complete blood picture, liver function tests, renal function tests).
• Echocardiography also will be obtained at the time of admission.
• Serum samples will be collected from patients at the time of admission for measuring the cardiac biomarkers in addition to serum cholesterol level.

All patients will be followed up during 3 months' period. At the end of 3 months, Serum samples will be collected from patients for measuring the biomarkers. Statistical tests appropriate to the study design will be conducted to evaluate the significance of the results. 8. Measuring outcome: The primary outcome is the change of serum levels of the measured cardiac biomarkers after 4 cycles of AC regimen.

Inclusion Criteria:

1. Women with newly diagnosed breast cancer and ≥ 18 years old.
2. Naive to chemotherapy.
3. Left ventricular ejection fraction (LVEF) > 55%.

Exclusion Criteria:

1. Concurrent administration of any other cholesterol-lowering therapy.
2. Evidence of hepatic dysfunction (alanine aminotransferase level more than three times the upper limit of the normal range)
3. Evidence of renal dysfunction (creatinine level more than three times the upper limit of the normal range).
4. Predisposing factors for rhabdomyolysis, including hypothyroidism, reduced renal function, any muscle or liver disease.
5. Concurrent administration of potent CYP3A4-inhibitors.
6. Pregnancy or breast-feeding