For the first-line treatment of breast cancer, the evidence suggests a potential advantage of paclitaxel and anthracycline over control. However, this evidence is not robust. There are ongoing, multicentre randomised controlled Phase III trials, one comparing epirubicin and paclitaxel versus epirubicin and cyclophosphamide (ABO1) and another comparing doxorubicin and paclitaxel versus doxorubicin and cyclophosphamide (EORTC) in the treatment of women with metastatic breast cancer. These trials should provide a clearer picture of the role of paclitaxel.
Both paclitaxel and docetaxel are licensed for use as second-line treatment for breast cancer. The evidence to support the use of paclitaxel in this context is not strong. There has been only one small trial and the cost-effectiveness of paclitaxel compared with mitomycin has not been proved.
There is a slightly greater body of evidence to support the use of docetaxel as a second-line treatment of advanced breast cancer, especially among women who are resistant to anthracyclines. In two trials there was an advantage in overall survival compared with control. However, there were no differences in quality of life. In addition, docetaxel was found to be of similar effectiveness to doxorubicin, so it may be useful in the treatment of women for whom anthracyclines are contraindicated. In three studies comparing docetaxel to vinorelbine, the one UK study found the cost per QALY gained of docetaxel was 14,050 GBP. Docetaxel was found to have highly favourable cost-effectiveness ratios in comparison with paclitaxel (incremental cost per QALY gained 1990 - 2431 GBP). These studies are weakened by the lack of direct comparison data.
Paclitaxel is licensed and recommended for use as first-line treatment for ovarian cancer. The best available evidence supports its use in combination with platinum in this context, with two trials showing significant improvement in overall survival. This treatment combination was also found to have potentially acceptable cost-effectiveness ratios (cost per QALY gained 5273 - 11,269 GBP). As the results of the ICON3 trial mature, they may be able to demonstrate for which subgroups of women this treatment is more or less appropriate. The mature results of this trial will also add to our understanding of the comparative costs and benefits of cisplatin and carboplatin. In addition, when complete and mature, the SCOTROC Phase III comparison of paclitaxel/carboplatin versus docetaxel/carboplatin as first-line chemotherapy in ovarian cancer should provide information on the comparative merits of these two taxanes.