Background: Taxoids are new chemotherapeutic agents effective in the treatment of breast cancer. Paclitaxel treatment has been reported to cause some cardiac side effects and both paclitaxel and docetaxel to cause mild, mainly sensory, peripheral neuropathy. Autonomic function tests are sensitive measures of autonomic neuropathy and cardiac regulation. The purpose of this study was to find out whether docetaxel changes neural cardiovascular regulation in breast cancer patients previously treated with anthracyclines.
Patients and methods: Nine women treated for metastatic breast cancer with docetaxel were studied prior to the docetaxel treatment and after the third or fourth course. Autonomic cardiovascular function tests were performed and heart rate and blood pressure variability were assessed with power spectrum analysis.
Results: Heart rate variability or the heart rate responses to the autonomic function tests did not change after docetaxel treatment. The blood pressure response to standing was enhanced and systolic blood pressure variability decreased after three to four cycles of docetaxel.
Conclusions: Docetaxel treatment did not deteriorate vagal cardiac control in breast cancer patients after exposure to epirubicin. The observed changes in blood pressure responses suggest that docetaxel changes sympathetic vascular control. However, these changes seem to be related to altered cardiovascular homeostasis rather than peripheral sympathetic neuropathy.