pCR After Neoadjvuant Chemotherapy Prognostic For TNBC Survival

Complete pathological response after neoadjuvant chemotherapy is significantly associated with survival endpoints in stage II–III triple-negative breast cancer

medwireNews: Patients with triple-negative breast cancer (TNBC) who achieve a complete pathological response (pCR) to neoadjuvant chemotherapy have significantly better survival outcomes than those who have residual disease at surgery, research suggests.

The phase II CALGB/Alliance 40603 trial previously demonstrated that stage II–III TNBC patients were more likely to achieve pCR if carboplatin or bevacizumab were added to the standard neoadjuvant chemotherapy regimen of paclitaxel, doxorubicin and cyclophosphamide, explained William Sikov, from Brown University in Providence, Rhode Island, USA, and co-authors.

The most recent results from the study, as reported at the 2015 San Antonio Breast Cancer Symposium in Texas, USA, show that over a median 39 months of follow-up 77 patients died and 110 patients experienced events, defined as ipsilateral invasive disease, local or distant recurrence, or death.

Three-year rates of event-free survival and overall survival were significantly higher in the 47% of patients who had achieved pCR of the breast and axilla than those who had not, with hazard ratios of 0.30 and 0.20, respectively. And this was true for all types of events recorded.

However, the study failed to show a significant association between the increase in pCR associated with carboplatin or bevacizumab treatment and an improvement in either survival endpoint.

“In regards to the question as to whether there is a benefit to adding either carboplatin or bevacizumab to standard chemotherapy for stage 2 or 3 TNBC, it is important to highlight that this is not a negative study,” William Sikov commented in a press release.

“Rather, it is underpowered, meaning that it was not designed to be large enough to prove or disprove a benefit for either agent.”

He concluded: “Our results need to be considered alongside data from prior and ongoing studies with these agents in TNBC.

“Going forward, the question is whether we want to commit the additional patients and resources necessary to answer this question or instead focus our research efforts in TNBC on other opportunities to improve outcomes.”

Reference

Sikov WM, Berry DA, Perou CM, et al. Abstract S2-05. Event-free and overall survival following neoadjuvant weekly paclitaxel and dose-dense AC +/- carboplatin and/or bevacizumab in triple-negative breast cancer: Outcomes from CALGB 40603 (Alliance). Presented at San Antonio Breast Cancer Symposium; San Antonio, Texas, USA: 8–12 December 2015.

medwireNews (www.medwireNews.com) is an independent medical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2015