Pathological response and circulating tumor cell count identifies treated HER2+ inflammatory breast cancer patients with excellent prognosis: BEVERLY-2 survival data.

Abstract

The BEVERLY-2 single-arm phase II trial assessed the efficacy and safety of combining neoadjuvant chemotherapy with bevacizumab and trastuzumab for the treatment of HER2-positive inflammatory breast cancer (IBC). Here, we report the results of a preplanned survival analysis at 3 years of follow-up, along with the association between outcome and circulating biomarkers and pathologic complete response (pCR). Patients received fluorouracil, epirubicin, cyclophosphamide, and bevacizumab (cycles 1-4) and docetaxel, trastuzumab, and bevacizumab (cycles 5-8) before surgery, followed by trastuzumab and bevacizumab for 30 weeks after surgery. Circulating tumor cell (CTC) and endothelial cell (CEC) counts were assessed at baseline, cycle 5, preoperative, postoperative, and at 1 year. Fifty-two patients were included. The 3-year disease-free survival (DFS) rate was 68% and overall survival (OS) rate was 90%. pCR (centrally reviewed) was strongly associated with 3-year DFS [80% and 53% in patients with/without pCR, respectively (P = 0.03)]. CTC detection also independently predicted 3-year DFS [81% vs. 43% for patients with <1 vs. ≥1 CTC/7.5 mL at baseline (P = 0.01)]. Patients with no CTCs detected at baseline and with pCR had a high 3-year DFS (95%). CEC changes during treatment had no prognostic value. Our study suggests that the prognosis of IBC relies on more than the achievement of pCR and highlights the role of early hematogenous tumor dissemination as assessed by CTCs. Combining these two prognostic factors isolates a subgroup of IBC with excellent survival when treated with bevacizumab- and trastuzumab-containing regimens.