Bevacizumab and albumin-bound paclitaxel treatment in metastatic breast cancer.

BACKGROUND: Miller et al demonstrated that the combination of bevacizumab and paclitaxel has significant activity in metastatic breast cancer (MBC). Because albumin-bound paclitaxel has been shown to have less toxicity, a better tumor delivery, and possibly better response for MBC, we combined it with bevacizumab to treat women with MBC.

PATIENTS AND METHODS: This is a retrospective analysis. Billing records from March 2005 through December 2006 were reviewed to identify all patients treated with a combination of albumin-bound paclitaxel/bevacizumab. A total of 40 women were identified. They received a minimum of 2 courses. Patients with measurable disease were monitored for response using Response Evaluation Criteria in Solid Tumors. Women with bone-only disease were monitored with positron emission tomography (PET)/computed tomography/magnetic resonance imaging and tumor markers. All response data were confirmed by independent review.

RESULTS: Of 33 women with measurable disease, 16 had objective responses to the albumin-bound paclitaxel/bevacizumab regimen (3 complete responses and 13 partial responses) for an overall response rate (ORR) of 48.5%. Median time to progression for responders was 128 days. Another 5 women had stable disease (SD) with a median duration of 135 days. Of 7 patients with bone-only disease, 2 had almost complete resolution of PET activity and 4 had SD (median, 148 days). Toxicity was acceptable with fatigue, neuropathy, pain, and hypertension being the most common complaints.

CONCLUSION: In our limited series of women with advanced, heavily pretreated MBC treated with albumin-bound paclitaxel/bevacizumab, we saw a 48.5% ORR. The regimen was well tolerated. Randomized studies are needed to confirm efficacy and safety of this combination in treating breast cancer.