P2-3-5 - Bevacizumab Plus Paclitaxel for Her2 Negative Advanced/Recurrent Breast Cancer: Assessment of Efficacy and Safety

Abstract

Background: Bevacizumab(BV) combined with paclitaxel(PAC) is one of a useful option to manage HER2 negative advanced/recurrent breast cancer(HER2-BC). However, importance of toxicity management have not been well discussed.Patients and methods: Patients(pts) having HER2-BC were considered to receive BV + PAC regimen. To avoid neurotoxicity, PAC was administered biweekly at the dose of 100mg/body. Additional PAC on day 8 for initial 2 or 3 cycles was applied to pts with emerging disease. BV was administered biweekly at the dose of 10mg/kg concurrently with PAC.Results: From October 2011 to December 2013, median age of 52(range 29-74), 50 female pts received BV + PAC. Estrogen receptor(ER) was positive in 38pts(76.0%), and 12pts(24.0%) revealed triple-negative. Median Ki67 rate was 25.4%(range 2.0-98.5). Disease statuses were as follows; recurrent 31 (62.0%), advanced 19(38.0%), visceral lesion(s) 30(60.0%), prior taxane 29(58.0%). Objective response rate(ORR) was 40.0%. Median time to treatment failure(TTF) was 195.0 days(95% confidence interval[CI] 89.0-364.0). In 20pts who received BV + PAC as 1st-line, ORR was 70.0% and median TTF was 321.0 days (95%CI 154.0-503.0). TTF was independent from ER, Ki67, visceral lesion or prior taxane. Gr2/3 HT associated with BV was seen in 23pts(46.0%), and they showed strong trend of superior TTF compared to pts with Gr0/1 HT regardless of treatment-line(P = 0.065, log-lank). Gr3 proteinuria was seen in 3pts and it was maintained by reduction of BV. Other toxicities were tolerable and no Gr3 sensory neuropathy or Gr4 HT was seen. However, 1pt with Gr2 neuropathy withdrew from the therapy due to the toxicity.Conclusions: We conclude 1) BV combined with dose-reduced PAC have a potential to control HER2-BC with less toxicity compared to conventional BV + PAC, and 2) treatement-related Gr2/3 HT is one of the significant predictive marker of BV + PAC therapy in HER2-BC.