Adjuvant Treatments for Triple-negative Breast Cancers

Conventional chemotherapy is the mainstay of adjuvant systemic treatment for most patients with early triple-negative breast cancer (TNBC). At present, comparisons between adjuvant chemotherapy regimens are retrospective in nature, and so the optimal drugs or drug combinations have not been established for patients with early TNBC. In retrospective subgroup analyses, taxanes are more effective than 5-fluorouracil in combination with cyclophosphamide and doxorubicin. Classical CMF (cyclophosphamide, methotrexate and 5-fluorouracil) has shown efficacy, whereas few data on the role of anthracyclines are available. An unplanned subgroup analysis of one randomised study suggests that capecitabine adds efficacy to a taxane-anthracycline regimen, but this observation requires confirmation. High-dose adjuvant chemotherapy is considered experimental. Ongoing trials are comparing standard adjuvant regimens with regimens that integrate an anti-angiogenic agent, a platin or maintenance capecitabine. Inhibitors of DNA repair or specific tyrosine kinases have not yet been addressed in the adjuvant setting. In the absence of data from prospective trials that focus on adjuvant therapy of early TNBC, several regimens, such as a taxane and an anthracycline-containing regimen or classical CMF may be considered reasonable choices.