Improvement of metastatic breast cancer survival over a 20-year period: Evidence from six consecutive clinical studies

Metastatic breast cancer (MBC) is quite sensitive to chemotherapy, with patients often benefiting from multiple lines of treatment. Continuation of chemotherapy until disease progression, if tolerable, prolongs disease control and improves patient outcomes. Compared to combination regimens, sequential single-agent chemotherapy provides similar efficacy and improved tolerability and may represent the preferred option for most patients. Numerous agents are available, but there are few data to advise optimal sequencing. Oral chemotherapeutic agents, including capecitabine and vinorelbine, have demonstrated significant efficacy in patients with MBC. These drugs prolong disease control with good tolerability, especially when used as single agents. In addition, oral chemotherapy reduces the time and cost associated with treatment and usually is preferred by patients if compared with intravenous delivery. Metronomic administration of oral chemotherapy also represents a promising therapeutic approach for select patients with MBC, inhibiting tumor progression through multiple mechanisms of action. Ongoing clinical trials are exploring metronomic regimens as a strategy to prolong disease control with favorable tolerability. Key data on the role for oral chemotherapy in the therapeutic landscape for MBC will be reviewed and accompanied by expert perspectives on important considerations for the integration of oral chemotherapeutic agents into the treatment of patients with MBC.