Preoperative Carboplatin–Paclitaxel–Bevacizumab in Triple-Negative Breast Cancer: Final Results of the Phase II Ca.Pa.Be Study

Purpose: The phase II Ca.Pa.Be trial evaluated preoperative carboplatin–paclitaxel in combination with bevacizumab in triple-negative breast cancer patients with previously untreated stage II–III disease. The primary aim was the assessment of the rate of pathologic complete response (pCR). Secondary aims included safety, breast-conserving surgery rate, and early response assessment with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Methods: Patients with hormone receptor-negative, HER-2-negative stage II–III breast cancer were eligible. Treatment included paclitaxel 80 mg/mq + carboplatin area under the curve (AUC) 2 on days 1, 8, and 15, combined with bevacizumab 10 mg/kg on days 1 and 15 each 28 days, for 5 courses. At baseline, patients underwent breast DCE-MRI, followed by a single dose of bevacizumab 5 mg/kg (day −6). DCE-MRI was repeated before the initiation of chemotherapy. Results: Forty-four patients were enrolled. Forty-three patients underwent surgery, and 22 (50 %) received breast-conserving surgery (conversion rate from mastectomy indication at baseline, 34.4 %). A pCR in breast and axillary lymph nodes occurred in 22 patients (50 %). Bevacizumab-associated adverse events (AEs) were mild: G1–2 hypertension and bleeding occurred in 6 (13.6 %) and 12 (27 %) patients, respectively. No G4 nonhematologic AEs were recorded. More frequent G3 AEs were liver function test abnormalities (6.8 %), and diarrhea and fatigue (4.5 % each). The only G3–4 hematologic toxicity was neutropenia (G3, 25 %; G4, 9 %). Early assessed DCE-MRI response parameters failed to predict pCR. Conclusions: The neoadjuvant anthracycline-free combination of weekly paclitaxel and carboplatin plus bevacizumab is active and safe in triple-negative breast cancer, and the rate of pCR is comparable to that observed with more intensive carboplatin- and bevacizumab-containing regimens. Further investigation is warranted.