The IBCSG recently launched a long-term observational study that will extend patient follow-up for an additional five years in order to provide further information on efficacy and side effects of five years of adjuvant hormone therapy. "The follow-up study includes collection of yearly updates of survival, disease status and long-term adverse events. We plan to continue to update results every two years. This study is critically important as more than 74% of the patients enrolled in BIG 1-98 were still alive without a relapse at their most recent study visit. Assessment especially of long-term side effects for these patients is critically important," he said.

"BIG 1-98 and other large randomised clinical trials have firmly established the benefits of adjuvant treatment programmes including aromatase inhibitors, such as letrozole. Improved disease control and extended survival will reduce burdens on healthcare systems by reducing the number of patients requiring treatment for metastatic breast cancer. Furthermore, the cost of aromatase inhibitor treatment will decrease in the near future as generic products become available," Prof Gelber added.

Professor Michael Baumann, president of ECCO said: "This 12-year update of the study sheds more light on the advantages of aromatase inhibitors over tamoxifen in the adjuvant treatment of early breast cancer. It also clearly demonstrates how important it is to perform long-term follow-up and analysis of clinical studies especially for breast cancer. Long-term analysis is essential for reliably ensuring the efficacy of treatments but also to detect potential long-term side-effects which may affect quality of life. Although it is very difficult and costly to perform such long-term trials, the return for optimising treatments for cancer patients cannot be overemphasised."

Commenting on the study, which he was not involved with, ESMO member Professor Christoph Zielinski from the Medical University of Vienna, Vienna, Austria, said: "The BIG 1-98 trial demonstrates the clinical benefits of the aromatase inhibitor, letrozole and also provides further insight into the biology of the disease and how to improve outcomes with the upfront use of letrozole, compared to tamoxifen. This is important for daily clinical practice."

Source: European Multidisciplinary Cancer Congress