Docetaxel and paclitaxel based chemotherapy regimens have a comparable efficacy in patients with metastatic breast cancer
A meta-analysis presented by Qi et al. during the 2012 annual symposium of the European Society for Medical Oncology (ESMO) demonstrates that docetaxel- and paclitaxel-based chemotherapy regimens have a comparable efficacy in the treatment of women with metastatic breast cancer. The meta-analysis also revealed that paclitaxel-based regimens are associated with less toxicity and better tolerability compared to docetaxel-based therapy.
The taxanes docetaxel and paclitaxel are both approved for the treatment of metastatic breast cancer. For the moment it is however unclear whether paclitaxel-based therapy is more efficacious than docetaxel-based therapies in this patient population. In this light, a meta-analysis was performed including seven randomised controlled trials comparing paclitaxel-based therapy with docetaxel-based regimens. The primary endpoint in this meta-analysis consisted of overall survival, while secondary objectives included progression-free survival, overall response rate, time to progression and grade 3/4 toxicity.
In total, the seven randomised studies included in this meta-analysis involved 1,694 patients with metastatic breast cancer. The meta-analysis results indicate that paclitaxel and docetaxel based treatment regimens are comparable in terms of overall survival (HR[95%CI]: 0.87[0.60-1.27]; p=0.476), progression-free survival (HR[95%CI]: 0.76[0.58-1.00]; p=0.052], time to progression (HR[95%CI]: 1.13[0.81-1.58]; p=0.459) and overall response rate (HR[95%CI]: 1.01[0.88-1.15]; p=0.915).
However, with respect to toxicity, the analysis revealed that, compared to docetaxel-based therapy, paclitaxel-containing chemotherapy is associated with significantly less grade 3/4 undesirable effects. This included anemia (RR[95%CI]: 0.64[0.44-0.94]; p=0.023), neutropenia (RR[95%CI]: 0.74[0.58-0.93]; p=0.011), febrile neutropenia (RR[95%CI]: 0.38[0.15-0.96]; p=0.041), thrombocytopenia (RR[95%CI]: 0.62[0.41-0.96]; p=0.033), mucositis (RR[95%CI]: 0.082[0.025-0.27]; p<0.0001), diarrhoea (RR[95%CI]: 0.194[0.081-0.47]; p<0.001) and fatigue (RR[95%CI]: 0.434[0.20-0.96]; p=0.039).
In summary, paclitaxel-based chemotherapy was shown to be as effective as docetaxel-based regimens but is associated with a more favourable toxicity profile. This was especially the case when used in a weekly regimen in elderly patients.
Reference
Qi W-X., Yao Y, Shen Z. et al. Paclitaxel-based versus docetaxel-based regimens in metastatic breast cancer: a systematic review and meta-analysis of randomised controlled trials. Presented at ESMO 2012, Abstract 326PD.
