Postmenopausal women with breast cancer benefit significantly from using zoledronic acid as an aid to chemotherapy, according to trial results presented at the 2011 European Multidisciplinary Cancer Congress* and published in the New England Journal of Medicine.1 Could this be the key to unlocking the breast cancer recurrence process as well as advancements toward new breast cancer therapy options? Researchers believe so.
The AZURE trial, led by Professor Robert Coleman at the Weston Park Hospital in Sheffield, UK, included 3360 patients with stage 2/3 breast cancer from 174 centers. Patients were randomized to receive chemotherapy and/or endocrine therapy, with or without zoledronic acid.
Researchers discovered the drug had little effect, except for those women who had previously undergone menopause 5 or more years prior to the study. For the postmenopausal patients receiving zoledronic acid, the overall survival rate was 85% compared to 79% for women who did not receive zoledronic acid. Furthermore, the drug’s effect was unrelated to the stage of the tumor, estrogen receptor status, and lymph node involvement.
“This is a small but significant increase,” Coleman explains. “The finding is not sufficient to be taken up on its own but in the context of other studies and additional data anticipated later in the year, it is likely to change practice.”
The results lead researchers to believe that bones may play a large role in the progress of breast cancer. “The effects on metastasis and recurrence outside bone suggests that the bone marrow is an important sanctuary for tumor cells which can be activated after, sometimes, many years of dormancy,” Coleman says. “With help from bone marrow stem cells, they may then spread via the blood stream to set up metastases at other sites.”
*The 2011 European Multidisciplinary Cancer Congress is the 16th congress of the European CanCer Organisation (ECCO), the 36th congress of the European Society for Medical Oncology (ESMO) and the 30th congress of European Society for Therapeutic Radiology and Oncology (ESTRO).
1.Coleman RE, et al. N Engl J Med. 2011;365(15). DOI: 10.1056/nejmoa1105195.
Source: ECCO