Breast-cancer deaths reduced by therapies

A large new study is providing good news about long-term survival for women with breast cancer.

Standard chemotherapy and hormone treatment work even better than researchers had expected, the study found. For middle-aged women with an early stage of the disease, combining the treatments can halve the risk of death from breast cancer for at least 15 years.

For instance, a woman younger than 50 with a tumor big enough to feel, but not invading her lymph nodes, would have a 25 percent risk of dying of breast cancer in the next 15 years if she had surgery but no drug therapy. Adding both chemotherapy and hormone treatment would drop her risk to 11.6 percent.

Among the most important findings was that a certain type of chemotherapy, already widely used, was most likely to save lives. It included six months of the drug Adriamycin, also called doxorubicin, or a related drug, epirubicin. Though the drugs cause hair loss and nausea, and in some cases heart problems, in the long run their benefits outweighed the risks, the studies found.

The greatest gains in survival came when the treatment also included five years of tamoxifen, a drug that blocks the effects of the hormone estrogen, which can feed some tumors. But tamoxifen helps only women with estrogen-sensitive tumors, about 60 percent.

"I think women should feel very encouraged by the progress that has been made," said Dr. Sarah Darby of Oxford University, an author of a 30-page report on the work that is being published today in The Lancet, the British medical journal. "Mortality rates are falling in the U.S. and the U.K., and are starting to fall in some other countries."

The study proves that drug therapy deserves credit for the dropping death rates, Darby said.

The findings come from an analysis of 194 studies involving 145,000 women in two dozen countries — the largest analysis ever of research results in cancer, and also one of the longest, with 15 years of follow-up in many cases. The analysis was paid for by the British government, not drug companies.