Annals of Oncology Advance Access published online on July 24, 2009
Annals of Oncology, doi:10.1093/annonc/mdp308
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Efficacy of carboplatin–taxane combinations in the management of castration-resistant prostate cancer: a pooled analysis of seven prospective clinical trials
1 Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
2 Beth Israel Deaconess Medical Center, Boston, MA
3 Department of Medicine and Surgery, Yale University, New Haven, CT
4 Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC
5 US Oncology, Inc., Houston, TX
6 Cancer Centers of North Carolina, Cary, NC, USA
7 Department of Urology, Shimane University School of Medicine, Izumo, Japan
8 Lank Center for Genitourinary Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
* Correspondence to: Dr M. M. Regan, Dana-Farber Cancer Institute, 44 Binney Street, Boston, MA 02115, USA. Tel: +1-617-632-2471; Fax: +1-617-632-5444; E-mail: mregan{at}jimmy.harvard.edu
Background: Docetaxel is associated with prolonged survival in castration-resistant prostate cancer (CRPC). Platinum compounds have modest but distinct single-agent activity. Carboplatin may have greatest potential for benefit when combined with taxanes. We investigated whether there is a subset of patients with CRPC for whom the efficacy of combination taxane–estramustine–carboplatin (TEC) chemotherapy may be greatest.
Patients and methods: Individual patient data (n = 310) were obtained from seven trials using TEC chemotherapy. Prostate-specific antigen (PSA) response was defined as 
50% post-therapy decline from baseline. Overall survival was defined from baseline to death from any cause. Logistic and Cox regression were used to investigate heterogeneity in outcome to TEC by patient and disease characteristics. Predicted survival probabilities were calculated from the Halabi Cancer and Leukemia Group B (CALGB) nomogram.
Results: The pooled PSA response proportion was 69% [95% confidence interval (CI) 56% to 80%]. There was no evidence of differential PSA response by disease characteristics. Established prognostic factors were associated with survival. The pooled 12-month survival estimate of 79% (95% CI 71% to 84%) was higher than the median 59% 12-month nomogram-predicted survival.
Conclusions: TEC chemotherapy has significant clinical activity in CRPC. A randomized, controlled trial evaluating the addition of carboplatin to taxane-based chemotherapy is needed to elucidate the value of carboplatin in CRPC.
carboplatin, estramustine, prostate cancer, taxanes
Received for publication October 28, 2008. Revision received May 5, 2009. Accepted for publication May 7, 2009.