Researchers have found a new approach to treat triple negative breast cancer with a common adjuvant breast cancer chemotherapy combination.

A team of researchers has identified a method for treating particularly aggressive forms of breast cancer that could potentially save thousands of lives each year. According to results from a SWOG clinical trial, those with tough-to-treat triple negative breast cancer, whose tumors also don't allow for double-strand DNA repair, fare better when treated with a common adjuvant breast cancer chemotherapy combination.

The trial results showed that a well-established drug combination - adjuvant doxorubicin and cyclophosphamide (AC) chemotherapy - works well in this patient population. The results also showed the value of collecting and preserving cancer tumor tissue. University of Kansas Cancer Center's Priyanka Sharma and her team used nearly 20-year-old tumour samples stored in SWOG's biospecimen bank to conduct their analysis. "We learned three interesting things from this trial," Sharma said. "First, we showed that assays tested in our study worked well in very old tissue samples. We also learned that 25 percent of triple negative breast cancer patients harbored BRCA 1 or BRCA2 mutations and tumors in these patients were HRD positive."

"However, presence of HRD was not restricted to just patients with BRCA mutations, as among patients without BRCA mutations, 55 percent also demonstrated tumor HRD. Finally, and most importantly, we learned that 67 percent of triple negative breast cancer patients - a solid majority - respond well to a standard, backbone chemotherapy combination. So, while, AC chemo is an old treatment, for many, it's still a good one. HRD status is a biomarker that, when identified, can potentially help a physician best tailor a chemotherapy treatment for that particular triple negative breast cancer patient." The study is published in Annals of Oncology.