LOS ANGELES — A class of drugs that has been increasingly used to treat breast cancer in recent years may not improve survival rates in younger women with the disease, researchers reported Thursday.
The medications — bone- building drugs called bisphosphonates — have generated enthusiasm among cancer researchers because of their potential to slow the growth of cancer cells in bone and improve bone strength. But a large study on a potent bisphosphonate called zoledronic acid, or Zometa, found that the drug did not improve survival for patients with early-stage breast cancer except among a subset of women who were five or more years past menopause.
Although more research is needed, the study, presented at the annual meeting of the San Antonio Breast Cancer Symposium, supports the drug’s potential merits for older, post- menopausal women but raises questions about whether premenopausal or early-menopausal women will benefit.
Also at the symposium Thursday, researchers reported that half of American women ages 40 or older failed to get an annual mammogram for breast cancer last year. The researchers expressed concern that women are confused by the debate about the effectiveness of the screenings.
The study, sponsored by Medco Health Solutions Inc., reviewed records for 1.56 million patients from January 2006 through December 2009. About 207,000 new cases of invasive breast cancer in women will be diagnosed and almost 40,000 women will die from the disease this year, according to the Atlanta-based American Cancer Society.
As death rates from the disease decreased over the past 10 years, the debate over how frequently to get a mammogram has grown. The cancer society recommends that women ages 40 or older get screened every year. In November 2009, the Preventive Services Task Force advised women 50 or older to undergo a mammogram only once every two years, and patients younger than 50 to get one only if they carry risk factors for the disease.
“As controversy becomes public and there’s so much back-and-forth, it becomes confusing for women,” said Milayna Subar, lead author of the study. “This study shows the need to put programs in place to educate women and remind them to do it.”
Bloomberg News contributed to this report.
