Influence of pharmorubicin on the left ventricular ejection fraction of patients with breast cancer: A mechanism study.

Breast cancer is a great public health problem. It remains unclear how pharmorubicin induces cardiac dysfunction in patients with breast cancer. Our study was aimed to explore the influence of pharmorubicin on the left ventricular ejection fraction (EF) of patients with breast cancer and its potential mechanism.

Patients with breast cancer were enrolled at the same hospital. Group I consisted of 135 samples, who were under treatment of pharmorubicin (200 mg/m²). Group II consisted of 144 samples, who were under treatment the of pharmorubicin (360 mg/m²). Group III was used as control group, which consists of 120 samples without treatment of pharmorubicin. Color Doppler ultrasonic inspection and measurement were performed to examine EF. Flow cytometry was performed to assess oxygen free radical level in hemocytes. Further combination therapy (N-acetylcysteine [NAC] + pharmorubicin) was provided for patients, and the same examinations were performed for the assessment of cardiac function and oxygen free radical level.

The ultrasound results showed that pharmorubicin treatment significantly jeopardized cardiac function, verified by decrease of both EF and fractional shortening (FS) (P < 0. 05). Moreover, such effect was dose-dependent. Oxygen free radical level was remarkably increased after pharmorubicin treatment (P < 0. 05), verified by flow cytometry. Adjunctive therapy of NAC decreased oxygen free radical level and improved cardiac function of patients with breast cancer, suggesting NAC ameliorated side effect of pharmorubicin treatment.Pharmorubicin treatment decreased EF and FS of patients with breast cancer through increasing oxygen free radical level in hemocytes. Adjunctive therapy of NAC could be a potential treatment to ameliorated side effect pharmorubicin treatment.