An updated meta-analysis of taxanes for metastatic breast cancer: 10 years on (#93)
The original Cochrane review showed that taxane-containing regimens improved survival, time to progression and objective tumour response compared to non-taxane regimens in women with metastatic breast cancer. We updated this review with new studies published in the last 10 years.
We searched the Cochrane Breast Cancer Group’s Specialised Register, MEDLINE, EMBASE and CENTRAL from 2003 to February 2013. International Clinical Trials Registries were searched for ongoing trials. Randomised studies were included, and study eligibility and quality were assessed by two authors. We used published hazard ratios (HRs) if available or estimates from other survival data for overall survival (OS) and time to progression (TTP); the O-E/V method (fixed-effect model) was used for meta-analysis. Objective tumour response and toxicity (G3/4) were presented as odds ratios (ORs) and combined using Mantel-Haenszel random-effects model. Quality of life data were recorded.
We identified 41 eligible studies including 20 new studies of moderate quality. The updated analysis had 6008 patients (4477 deaths) whereas the original review contained 3643 patients (2621 deaths). The HR for OS was 0.93 (95% confidence interval (CI) 0.88-0.99, P=0.02, moderate heterogeneity) favouring taxanes, and this effect persisted in first-line trials (HR 0.93; CI 0.87-0.99, P=0.03). There was a significant difference in favour of taxanes for TTP (HR 0.92, CI 0.87-0.97, P=0.002) and objective tumour response in assessable women (OR 1.39; CI 1.26-1.53, P<0.00001; substantial heterogeneity). Taxanes were associated with increased risk of neurotoxicity (OR 5.70 CI 3.78-8.59, P<0.00001) but less nausea/vomiting compared to non-taxane regimens (OR 0.59 CI 0.43-0.81, P=0.001). Leukopenia did not differ between the two groups.
This updated review confirmed the benefits in survival, TTP and tumour response from taxanes in women with metastatic breast cancer. The degree of heterogeneity encountered suggests that taxane-containing regimens are more effective than some, but not all, non-taxane-containing regimens.
- the first two authors contributed equally