Docetaxel and autonomic cardiovascular control in anthracycline treated breast cancer patients

Background: Taxoids ave new chemotherapeutic agents effective in the treatm ent of breast cancer Paclitaxel treatment has been reported to cause some c ardiac side effects and both paclitaxel and docetaxel to cause mild, mainly sensory, peripheral neuropathy. Autonomic function tests ale sensitive mea sures of autonomic neuropathy and cardiac regulation. The purpose of this s tudy was to find out whether docetaxel changes neural cardiovascular regula tion in breast cancer patients previously treated with anthracyclines. Pati ents and methods: Nine women treated for metastatic breast cancer with doce taxel were studied prior to the docetaxel treatment and after the third or fourth course. Autonomic cardiovascular function tests were performed and h ear? rate and blood pressure variability were assessed with power spectrum analysis. Results: Heart rate variability or the heart rate responses to th e autonomic function tests did not change after docetaxel treatment. The bl ood pressure response to standing was enhanced and systolic blood pressure variability decreased after three to foul cycles of docetaxel. Conclusions: Docetaxel treatment did not deteriorate vagal cardiac control in breast ca ncer patients after exposure to epirubicin. The observed changes in blood p ressure responses suggest that docetaxel changes sympathetic vascular contr ol. However, these changes seem to be related to altered cardiovascular hom eostasis rather than peripheral sympathetic neuropathy.