Efficacy of gemcitabine-based chemotherapy in metastatic breast cancer: a meta-analysis of randomized controlled trials

Abstract

Objectives:

To compare the effects of gemcitabine-based chemotherapy and gemcitabine-free regimens, a meta-analysis of all relevant randomized controlled trials was performed to investigate the improvement in overall response rate (ORR), time to progression (TTP), and overall survival (OS). A subgroup of gemcitabine-based doublet compared with single agent was also analyzed.

Methods:

The PubMed and Embase databases were searched for relevant publications reporting randomized controlled trials comparing gemcitabine-based chemotherapy and gemcitabine-free regimens between January 1990 and December 2012. Hazard ratios (HRs) with their 95% confidence intervals (CIs), or data for calculating HRs with 95% CI were derived.

Results:

Nine trials with a total of 2651 patients were included in this meta-analysis. Compared with gemcitabine-free chemotherapy, gemcitabine-based therapy demonstrated no improvement in terms of ORR (HR 1.09, 95% CI 0.73–1.62; P = 0.67), TTP (HR 0.91, 95% CI 0.72–1.15; P = 0.44) and OS (HR 1.05, 95% CI 0.88–1.25; P = 0.60). In a subgroup including patients who received adjuvant chemotherapy containing anthracyclines or taxanes, sub-analysis assessment revealed that gemcitabine-based doublets were superior to monotherapy in ORR (HR 1.64, 95% CI 1.26–2.12; P = 0.0002) and TTP (HR 0.71, 95% CI 0.62–0.81; P < 0.00001), but no benefit was observed for OS (HR 0.90, 95% CI 0.79–1.03; P = 0.14). The rates of grade 3 and 4 anemia (HR 2.02, 95% CI 1.35–3.02; P = 0.006), neutropenia (HR 2.33, 95% CI 1.37–3.63; P = 0.01), and thrombocytopenia (HR 8.31, 95% CI 5.00–13.82; P < 0.0001) were significantly higher in the gemcitabine-based arm.

Conclusions:

The present study suggests that gemcitabine-based chemotherapy was as effective as gemcitabine-free chemotherapy in patients with metastatic breast cancer with increased hematological toxicity. Subgroup analysis indicated that adding gemcitabine to monotherapy might be more effective.

Keywords::

• Efficacy
• Gemcitabine
• Meta-analysis
• Metastatic breast cancer
• Toxicity

Transparency

Declaration of funding

The authors received no payment in preparation of this manuscript.

Declaration of financial/other relationships

W.L., H.W., and X.L. have disclosed that they have no significant relationships with or financial interests in any commercial companies related to this study or article.

CMRO peer reviewers may have received honoraria for their review work. The peer reviewers on this manuscript have disclosed that they have no relevant financial relationships.