Researchers involved in two separate studies say two types of existing inexpensive generic drugs show promise for reducing deaths from breast cancer.
Postmenopausal women with early breast cancer can see improved survival prospects with either of the two classes of drugs, known as aromatase inhibitors and bisphosphonates, they are reporting.
Using both types together could increase the benefits while lessening some of the side effects of the drugs, they add.
The results of the two trials have been announced by the Early Breast Cancer Trialists' Collaborative Group, a worldwide collaboration created at the University of Oxford in England to collect, every few years, all the findings of randomized trials on treatments for early breast cancer.
Aromatase inhibitors are a type of hormone-suppressing drugs often prescribed to postmenopausal breast and ovarian cancer patients.
Taking aromatase inhibitors for 5 years reduced the risk of postmenopausal women with breast cancer dying of their disease by 40 percent within 10 years of starting treatment, compared with no hormonal treatment, a study published in the Lancet reported.
"The evidence on aromatase inhibitors has been accumulating for well over a decade, but it has taken this huge and complex study to make sense of all the data, and provide a firm basis for clinical guidelines," said Paul Workman of the Institute of Cancer Research in London. "It tends to be the discovery of new treatments that grabs the headlines, but it is just as important to maximize the benefit patients get from existing treatments through major, practice-changing studies like this."
A separate study looked at bisphosphonates, which are usually prescribed for treating osteoporosis but have been found to also reduce the risk of breast cancer recurring in post-menopausal women.
When breast cancers spread, the most common site for that spread is to bone, researchers at Sheffield University in England point out.
Bisphosphonates alter the microenvironment of bone, making it less hospitable to cancer cells and so reduce the risk of cancer recurrence in the bone and in other organs, they explain.
Their study suggests that, in postmenopausal women, bisphosphonate treatment could reduce bone recurrence by 28 percent and also reduced the risk of death from breast cancer by 18 per cent during the first 10 years following diagnosis.
"These studies provide really good evidence that both of these inexpensive, generic drugs can help to reduce breast cancer mortality in post-menopausal women," said Richard Gray of the University of Oxford, who served as lead statistician for both the aromatase and the biosphosphonate studies.
