Palliative Therapy for TNBC

Breast cancers that do not express the estrogen and progesterone receptors and also do not overexpress HER2 are collected together and labeled triple negative . These tumors are not defined by a single molecular defect or target but some of them share deficient BRCA protein function, a basal genetic or phenotypic profile while others have unique attributes (such as expression of the androgen receptor). These tumors have recently been seen to represent a special challenge because on the one hand they may be especially sensitive to optimization of conventional adjuvant chemotherapy regimens, but on the other, they have not been effectively treated with less toxic targeted therapies. The latter challenge may be resolved through the growing recognition that these tumors are not a single entity but instead represent several or many distinct subtypes such that progress will be made through further dissection of their relevant biology. Recent advances building on this approach include the demonstration that platinum salts may be more active in TNBC when BRCA mutations are present, activity for PARP inhibitors in both mutation carriersand also in patients given specific chemotherapy agents, and demonstration of activity for a range of single agents in selected patients such as those with expression of the androgen receptor positive treated with anti-Androgens.