Lisa Carey, M.D., of the University of North Carolina, provided an update on the management of metastatic triple-negative breast cancer at the 2013 San Antonio Breast Cancer Symposium today. It was a clear overview of previous research, demonstrating that TNBC is a family of diseases, with varying subtypes that react differently to treatment.
Some of her points:
• 49 percent of all TNBC cases are basal-like.
• 30 percent are claudin-low, a new subtype that researchers are just beginning to understand.
• Preclinical studies show that platinum drugs may be especially effective against basal-like TNBC.
• Conventional chemotherapy is effective against metastatic TNBC; however, as with all stage IV disease, the duration of response is often short. Several studies have found median survival after diagnosis of stage IV disease of approximately 1-2 years.
• PARP inhibitors are effective against BRCA-associated TNBC.
• Weekly paclitaxel was more effective than ixabepilone and less toxic than albumin-bound nab-paclitaxel in the CALGB 40502 study.
• Eribulin (a halichondrin B analogue) was effective in the EMBRACE study.
• A phase III comparison of eribulin and capecitabine may show a slight advantage for TNBC.
• Both eribulin and capecitabine are “reasonable choices” for TNBC.
• Alternatives include anthracyclines, platinum drugs, gemcitabine, and doublet regimens.
• Bevacizamab (Avastin) plus chemo improved progression-free survival in metastatic TNBC but had zero effect on overall survival. Researchers do not know why.
• Randomized clinical trials are ongoing.
• Androgen-fighting drugs may successfully fight androgen-sensitive subsets of TNBC, as demonstrated at last year's SABCS.
"To advance therapy in metastastic TNBC, we will need to better match the tumor to the target," she said. TNBC may demonstrate that the old strategy of "one size fits all" treatment no longer works for any type of cancer.
Read more about TNBC in my book, Surviving Triple-Negative Breast Cancer.