Metronomic chemotherapy for advanced breast cancer patients.

Metronomic chemotherapy refers to the minimum biologically effective dose of a chemotherapy agent given as a continuous dosing regimen with no prolonged drug-free breaks that leads to antitumor activity. This schedule seems to have not only a direct cytotoxicity on cancer cells but also an effect on the tumor microenvironment by inhibiting tumor angiogenesis and modulating immune response. Metronomic chemotherapy was widely investigated in patients with breast cancer. The results of these studies showed that this strategy is not only effective but has a low toxicity profile too, proposing as a promising strategy for breast cancer patients. In this review we summarize the results of Phase II and III studies evaluating metronomic therapy in metastatic breast cancer.