Background
Various clinical trials and real-life studies have tried to explore the value of nab-paclitaxel mono-chemotherapy for metastatic breast cancer (MBC). The safety and efficacy of nab-paclitaxel needs to be systematically evaluated.
Methods
Electronic searches for prospective clinical trials containing nab-paclitaxel monotherapy for MBC were performed. Requisite data were extracted, integrated and analyzed from the included studies according to different purposes using systematic review and meta-analysis.
Results
22 studies with 3287 MBC patients were included. 1685 MBC patients received nab-paclitaxel as first-line therapy, 640 patients as further-line therapy, and 962 patients as mixed-line therapy. 1966 MBC patients (60.40%) received nab-paclitaxel weekly, while 1190 patients (36.56%) received nab-paclitaxel triweekly and 99 patients (3.04%) biweekly. The overall incidence of all grades neutropenia, leukopenia, peripheral sensory neuropathy, and fatigue was 52% (95% CI, 38%-66%), 58% (95% CI, 43%-73%), 58% (95% CI, 48%-68%), and 49% (95% CI, 41%-56%) respectively. The overall response rate (ORR) was 40% (95% CI, 35%-45%) and the clinical benefit rate (CBR) was 66% (95% CI, 59%-73%) following nab-paclitaxel monotherapy. The median progression free survival (PFS) was 7.64 months (95% CI, 6.89–8.40 months) and the median overall survival (OS) was 24.51 months (95% CI, 21.25–27.78 months). According to the meta-regression analysis, grade 3/4 neutropenia occurred less frequently in Her-2 negative patients compared with all population (P = 0.046). Patients who received first-line nab-paclitaxel monotherapy showed higher ORR (P = 0.006) and longer PFS (P = 0.045). Patients who received further-line therapy was demonstrated to have shorter median OS versus first- and mixed-line therapy. Efficacy outcomes were not affected by the administration schedule. However, patients appeared to have more superior ORR (P = 0.044) and longer PFS (P = 0.03) along with the increasing dosage of nab-paclitaxel under the same schedule.
Conclusions
Both weekly and triweekly nab-paclitaxel mono-chemotherapy were proved to be effective for MBC with generally reasonable toxicity profiles. Higher ORR, longer PFS and OS would be achieved in patients treated with nab-paclitaxel as first line. Increasing nab-paclitaxel dosage would result in better tumor control (higher ORR and PFS). Changing nab-paclitaxel schedule had no benefit on ameliorating the overall survival.