Therapies Cut Death Risk, Breast-Cancer Study Finds
May 13, 2005
Therapies Cut Death Risk, Breast-Cancer Study Finds - New York Times
By DENISE GRADY
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 under 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, Dr. 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.
The women in the studies all had relatively early cancers. Some were confined to the breast and some had spread to nearby lymph nodes, but none had reached other organs. All the women had surgery, and some had radiation. Some had no drug treatment, but others had chemotherapy or hormone treatment, or both.
The use of chemotherapy varied because in the 1980's, when many of the studies began, there was not enough evidence to tell whether women with early breast cancers needed drug treatment after surgery, and some doctors argued vehemently that they should not be exposed to the risks of chemotherapy.
All the studies included in the analysis were the type considered most reliable, known as randomized controlled trials, meaning that women were assigned at random to one treatment or another, and their outcomes compared.
An astonishing finding, Dr. Darby said, is that the benefits of treatment actually increase over time, even after the treatment is done, so that the elevation in survival rates in women who took the drugs compared with those who did not is even greater after 10 to 15 years than it was after 5 years.
"Very few doctors would have guessed that beforehand," Dr. Darby said.
For example, the study found that women under 50 who received chemotherapy (not hormone treatment) had a 15.7 percent death rate after five years, compared with 20 percent in women without chemotherapy. But after 15 years, the difference was even greater, a full 10 percentage points - a 32.4 percent death rate in treated women, compared with 42.4 percent in the controls.
Older women also benefited, though not as much. But not enough women 70 or over were included in the studies to determine the drugs' value for them.
The study also helps allay fears that delayed side effects from tamoxifen or chemotherapy might prove so deadly that women would in essence just be trading breast cancer for another cause of death. That did not occur; the increased risk of death linked to the drugs was only 0.2 percent.
Dr. Stephen Chia of the British Columbia Cancer Agency, an author of a commentary on the study, said he expected further declines in death rates from breast cancer because newer drugs, already in widespread use, worked even better than the ones used in the studies on which today's findings were based.
Therapies Cut Death Risk, Breast-Cancer Study Finds - New York Times
By DENISE GRADY
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 under 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, Dr. 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.
The women in the studies all had relatively early cancers. Some were confined to the breast and some had spread to nearby lymph nodes, but none had reached other organs. All the women had surgery, and some had radiation. Some had no drug treatment, but others had chemotherapy or hormone treatment, or both.
The use of chemotherapy varied because in the 1980's, when many of the studies began, there was not enough evidence to tell whether women with early breast cancers needed drug treatment after surgery, and some doctors argued vehemently that they should not be exposed to the risks of chemotherapy.
All the studies included in the analysis were the type considered most reliable, known as randomized controlled trials, meaning that women were assigned at random to one treatment or another, and their outcomes compared.
An astonishing finding, Dr. Darby said, is that the benefits of treatment actually increase over time, even after the treatment is done, so that the elevation in survival rates in women who took the drugs compared with those who did not is even greater after 10 to 15 years than it was after 5 years.
"Very few doctors would have guessed that beforehand," Dr. Darby said.
For example, the study found that women under 50 who received chemotherapy (not hormone treatment) had a 15.7 percent death rate after five years, compared with 20 percent in women without chemotherapy. But after 15 years, the difference was even greater, a full 10 percentage points - a 32.4 percent death rate in treated women, compared with 42.4 percent in the controls.
Older women also benefited, though not as much. But not enough women 70 or over were included in the studies to determine the drugs' value for them.
The study also helps allay fears that delayed side effects from tamoxifen or chemotherapy might prove so deadly that women would in essence just be trading breast cancer for another cause of death. That did not occur; the increased risk of death linked to the drugs was only 0.2 percent.
Dr. Stephen Chia of the British Columbia Cancer Agency, an author of a commentary on the study, said he expected further declines in death rates from breast cancer because newer drugs, already in widespread use, worked even better than the ones used in the studies on which today's findings were based.
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