Metronomic chemotherapy is the frequent administration of low (and, therefore, relatively non-toxic) doses of chemotherapy agents for a long time period, resulting in the destruction of endothelial cells lining newly formed blood vessels supplying the tumor. Thus, the metronomic chemotherapy is intended to inhibit the growth of new blood vessels (a process called angiogenesis), which otherwise would nourish the tumor.
Metronomic chemotherapy is an experimental approach that is being investigated in cell lines in the laboratory, animal models of cancer, and clinical trials in patients with solid tumors (such as breast cancer). Some studies involve a combination of metronomic chemotherapy and anti-angiogenic drugs that suppress the growth of new blood vessels supplying the tumor.
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