A prospective phase II clinical trial identifying the optimal regimen for carboplatin plus standard backbone of anthracycline and taxane-based chemotherapy in triple negative breast cancer

Addition of platinums to combination chemotherapy for triple negative breast cancer (TNBC) has shown efficacy and is increasingly accepted in the clinic, yet optimal delivery is unknown. A prospective clinical trial with TNBC patients was conducted to determine the optimal chemotherapy regimen to deliver carboplatin with standard dose dense ACT. Tissue microarray was conducted to isolate markers indicative of response to treatment. 90 TNBC patients were enrolled onto our trial. The most successful version placed the carboplatin on the second and final paclitaxel treatment with liberal hematological parameters. Our final regimen had the lowest grade 3 or 4 toxicities, no delays, no dose reductions of carboplatin, and 32% reduction in paclitaxel doses. Stage I (AJCC7) patients did well with carboplatin-based chemotherapy with zero relapse rate. Reduction in protein levels of androgen receptor and PD-L1 were found to be potential indicators of patient relapse. We have optimized a protocol for the addition of carboplatin to standard of care chemotherapy in TNBC patients. Early data indicates reduced protein levels of androgen receptor and PD-L1 as indicators of response to treatment. Trial registration This trial was registered at Canadian Cancer Trials.

Automated summary

A clinical trial was conducted to determine the optimal chemotherapy regimen for adding carboplatin to standard treatment for triple negative breast cancer (TNBC). The results showed that placing carboplatin on the second and final paclitaxel treatment had the best efficacy with reduced toxicities. Lower levels of androgen receptor and PD-L1 proteins may serve as indicators of treatment response and risk of relapse in TNBC patients.