New data from ATAC, one of the world’s largest and longest-running studies in postmenopausal women with early breast cancer, reinforces that anastrozole can help many more women live cancer-free, for longer.
For the first time, anastrozole has been shown to be the only treatment of its type to be increasingly better than tamoxifen in preventing tumours from returning. If cancer returns, women are much more likely to die therefore, preventing breast cancer from returning (“recurrence”) is key to saving lives.
The landmark results, presented at the prestigious annual San Antonio Breast Cancer Symposium (SABCS) and also published online in The Lancet Oncology, also show that even four years after a woman’s treatment ends, the protective effect of anastrozole in reducing the risk of hormone-sensitive early breast cancer from returning continues to increase.
Overall, women in the ATAC trial taking anastrozole were 24% less likely to have their cancer come back, compared with those taking tamoxifen. This demonstrates the long-term impact of treatment decisions made at diagnosis and confirms the importance of starting treatment with anastrozole to help more women beat this devastating disease.
Breast cancer currently affects 1.1 million women worldwide per year and hormone-sensitive early disease accounts for around 75% of all cases of breast cancer in postmenopausal women.
Presenting the data at SABCS, Professor John Forbes, Newcastle Mater Misericordiae Hospital, Australia said: “Preventing recurrence is the primary goal in breast cancer management. If we can stop the cancer from returning, we can save more lives, more often. These exciting long-term follow-up data show that anastrozole is a more effective treatment option than tamoxifen for postmenopausal women with hormone-sensitive early stage disease, thus it is imperative these women get the most effective treatment at the earliest opportunity after diagnosis.”
He added: “Prior to the ATAC trial, tamoxifen was the standard of care for women with hormone-sensitive disease, with substantial evidence to support its crucial place in practice. However, these new 100-month data from ATAC show us that compared with tamoxifen, anastrozole can significantly reduce the risk of recurrence and minimise life-threatening side effects. Most encouragingly, the data also show us that the protective effect of anastrozole lasts well beyond the standard treatment period of five years and in my opinion confirms there is no longer any rationale for prescribing tamoxifen.”
A recent global survey showed that more than 70% of physicians believed that telling a patient her breast cancer had come back was worse than giving a diagnosis of early breast cancer.
Recurrence, in the same breast, in the opposite breast or at a distant tumour site means that the cancer is more likely to be incurable and the patient is at risk of a bad outcome. It is therefore essential for both patients and their physicians to know they are on a better therapy than tamoxifen to prevent the disease returning.
The impact of treatment on quality of life is also an important consideration in early breast cancer, and data have shown that the clinical benefits of anastrozole are achieved without adversely affecting the quality of patients’ lives.
“The ATAC 100-month data confirm that anastrozole is now the gold standard treatment for post-menopausal women with hormone-sensitive early breast cancer, irrespective of their recurrence risk, and is set to improve the outcomes of patients worldwide,” said Professor Anthony Howell, Christie Hospital, UK.