In women with hormone-resistant breast cancer (ie, oestrogen-receptor (ER) negative breast cancer*), even the older chemotherapy regimens of the 1970s and 1980s were safe and have improved long-term survival, according to an Article in this week’s issue of The Lancet. Modern chemotherapy regimens should be even more effective, the authors conclude.
A worldwide collaboration, The Early Breast Cancer Trialists’ Collaborative Group (EBCTCG), was set up in 1984–85 to coordinate 5-yearly meta-analyses of centrally collected data from women in all randomised trials of the treatment of early breast cancer. The most recent report assesses the evidence of the past 30 years in chemotherapy for ER-negative disease.
Professor Sir Richard Peto (CR-UK Clinical Trial Service Unit, University of Oxford, UK) and colleagues did meta-analyses of individual patient data for 6000 women with ER-negative disease in 46 randomised trials of polychemotherapy versus no chemotherapy (trial start dates1975–96, mean 1984).
The researchers found that polychemotherapy safely reduced recurrence, breast cancer mortality, and death from any cause, not only in women younger than 50 years, but also in those aged 50–69 years. According to the authors, the 10-year risks of death from any cause were 25% versus 33% in women younger than 50 years of age, and 39% versus 45% in aged 50–69 years. The authors also confirmed that the hormonal drug tamoxifen had little effect on recurrence or death in women who were classified in these trials as having ER-negative disease, and that it did not significantly modify the effects of polychemotherapy.
The authors say: “For women with hormone-resistant breast cancer, the effects of chemotherapy on the risk of recurrence and death are definite, but were only of moderate size. Modern chemotherapy regimens should produce greater proportional reductions in recurrence and breast cancer mortality than the regimens tested in these trials**.”
In an accompanying Comment, Dr Rinat Yerushalmi and Dr Karen Gelmon (British Columbia Cancer Agency, Vancouver, Canada) say: “The latest update from the EBCTCG further confirms the contribution of chemotherapy to decreasing recurrence of oestrogen-receptor-negative breast cancer. Efforts should now be directed towards the establishment of finer definitions of subtypes of such cancers, the study of less debilitating but active regimens, and the development of new strategies for those who are not cured by conventional chemotherapy.”
Professor Sir Richard Peto, Co-director, CR-UK Clinical Trial Service Unit, University of Oxford, UK. T) +44 (0)1865 746 801 secretary@ctsu.ox.ac.uk
(Professor Peto would prefer to be contacted on Wednesday January 2 when he will be on his mobile T) +44 (0)7771 960329
Comment: Dr Karen Gelmon, British Columbia Cancer Agency, Vancouver, Canada. kgelmon@bccancer.bc.ca
Notes to Editors
*ER-negative breast cancer is the less common of the two main types of breast cancer. Unlike ER-positive breast cancer, it cannot respond to the normal hormonal treatments. In addition, about two-thirds of the cases of ER-negative breast cancer cannot respond to newer treatments such as herceptin. Chemotherapy is then the only effective way of treating any disease that has already spread beyond the breast and local lymph nodes.
**Quote directly from Professor Peto, and cannot be found in text of article.
View the PDF associated with this press release at http://multimedia.thelancet.com/pdf/press/Adjuvant chemotherapy p29-40 Jan 5.pdf.
Journal
The Lancet