Bone Drug May Extend Lives of Young Women With Breast Cancer
Study: Premenopausal Women Given Zometa 37% Less Likely to Die
A Mixed Bag
Animal and lab research suggests that bisphosphonates may fight breast cancer in a number of ways -- by directly killing tumor cells, by cutting off their blood supply, or by stimulating the immune system to mount an attack against the tumor.
Studies in women, though, have had mixed results. At last year's meeting, researchers reported that Zometa did not appear to prevent recurrences or cut deaths in most postmenopausal women, who account for three-fourths of all breast cancer cases.
Two other major studies also failed to show an overall benefit in terms of preventing cancer from coming back, says Harold Burstein, MD, PhD, of the Dana-Farber Cancer Institute in Boston.
And in another study presented at this year's meeting, the bisphosphonate pill Boniva failed to lower the risk of recurrence.
On the plus side, another new study showed postmenopausal women who received Zometa right away were 34% less likely to have a recurrence compared to those who were started on the bone drug at a later time.
All that makes Burstein hesitant to use Zometa or other bisphosphonates as cancer-fighting drugs.
"There are mixed reports in different patient populations with inconsistent benefits. At this point, there are insufficient data to make a recommendation one way or the other regarding using these drugs to prevent breast cancer recurrence,” Burstein tells WebMD.
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.