Here's what Knight Ridder said yesterday:
Breast cancer pill poses a dilemma | New treatment raises risk of other
diseases
Raja Mishra
KNIGHT RIDDER NEWSPAPERS
07-Apr-1998 Tuesday
WASHINGTON -- With a major advance in breast cancer treatment announced
yesterday, American women are facing a whole new set of risks and benefits
as they weigh how to best protect themselves from a fearful disease that
kills about 43,500 a year.
Some who have considered surgically removing a healthy breast to avoid
future breast cancer can now contemplate simply taking a daily pill to
prevent the disease. But the pill, the drug tamoxifen, brings with it
increased risk of uterine cancer and blood clots in the lungs.
"One has to make a balanced decision . . . that must be discussed with a
woman's physician," cautioned Dr. Harold Varmus, director of the National
Institutes of Health and a Nobel prize-winning cancer researcher, in
announcing the test results. But he added: "There are clear benefits in
tamoxifen for women at increased risk."
As the news of the new treatment began filtering through the medical
community, doctors began to reconsider how they will treat breast cancer.
"We'll have to explain to patients the benefits of the medicine and the
risks. Then say, 'Think this over, Mrs. Jones, and make a decision,' " said
Dr. Thomas Doyle, a senior doctor in the oncology division at Henry Ford
Hospital in Detroit.
A large-scale, four-year study found women at high risk for breast cancer
reduced their chances of getting the disease 45 percent by taking
tamoxifen, researchers reported yesterday.
The results haven't yet been published, and the cancer treatment staff at
some hospitals, such as Cedars-Sinai Medical Center in Los Angeles, said
they wouldn't be advising women on use of the drug until they get a chance
to thoroughly review the data. Doctors elsewhere are exercising similar
caution.
Tamoxifen is manufactured by Zeneca, a Delaware-based drug company. A
month's supply is expected to cost between $80 and $120.
It's likely family doctors and gynecologists will be the medical
practitioners first bombarded with questions as news of the drug spreads,
since they see women before cancer develops. While detailed scientific
results aren't yet available, these doctors will be able to discuss new and
welcome options with women, said Doyle.
Doctors must now help women weigh the advantages of tamoxifen with its
serious side effects. The drug produced higher rates of uterine cancer and
blood clots in the lung when women over 50 years old took it. Researchers
said those conditions are rare enough that the benefits of tamoxifen
outweigh the risks.
"I would imagine women at high risk would consider using this drug, and the
small percentage of women who are considering preventative mastectomies
will not have them," said Doyle.
The first key step is determining the risk of getting breast cancer, a
highly individual calculation, said researchers.
The strongest risk factor is age. The older a woman, particularly if she is
over 50, the greater the risk. If one or more close family members have had
breast cancer, then risk is higher. The age of a woman at her first birth,
particularly if she was younger than 25, decreases risk. The younger her
first period, the greater the risk. The more breast biopsies she has had,
the greater the risk.
Recent advances in genetic testing have shown women who have the genetic
mutations called BRCA1 and BRCA2 have higher risks. But when the tamoxifen
study began, genetic testing wasn't available, so there are no conclusions
about how the drug affects the breast cancer rates of women with this
mutation. These results are expected within a year.
All of this must be considered before a woman makes a decision about the
drug, said researchers.
Women over 50 who took the drug were three times as likely to suffer blood
clots in the lung; two of the 13,000 women in the study died of such clots.
The same group of older women who took the drug had double the rates of
cancer of the lining of the uterus. These women were treated by
hysterectomy, the removal of the uterus, and none died.
But the occurrence of these two conditions is far lower than the rates of
fatal breast cancer, researchers said. "The frequency of the risk is much
less than the frequency of the benefits," said Dr. Leslie Ford, an
associate director at the National Cancer Institute.
Despite these difficult choices, it seems clear the drug marks a
significant advance in the fight against breast cancer.
"For the first time in history we have evidence breast cancer can not only
be treated but prevented," said Dr. Bernard Fisher, a professor at the
Allegheny University of the Health Sciences, in Philadelphia, one of the
main researchers.
Tamoxifen was tested on a group of 13,388 women with a high risk of breast
cancer. Half of them took the drug and the rest took a placebo, a pill that
has no effect on the body. The results were:
Among women between 35 and 49 years old, 38 women who took tamoxifen
developed breast cancer, compared with 59 in the placebo group.
Among women between 50 and 59 years old, 24 in the tamoxifen group
developed the disease, compared with 46 in the placebo group.
Among women over 60, there were 23 in the tamoxifen group who got breast
cancer, compared with 49 in the placebo group.
The trial began in April 1992 but was stopped four weeks ago, more than a
year earlier than scheduled, because tamoxifen's benefits were so obvious,
said researchers. On average, tamoxifen reduced the rate of breast cancer
in high-risk women by 45 percent.
"It's not often we get to present results of a 45 percent reduction," said
Dr. Richard Klausner, director of the National Cancer Institute, which
helped fund the study. He added that, despite theories that changes in
exercise and diet can reduce breast cancer, tamoxifen is the first proven
risk-reducer.
Tamoxifen has been used to treat patients with advanced breast cancer for
25 years. More recently it has been used in combination with radiation
therapy. Researchers noticed when women with cancer in one breast took the
drug, they did not develop it in the other. They decided to begin the
study, the results of which were reported yesterday.
Tamoxifen is one of a class of drugs called Selective Estrogen Response
Modifiers. These drugs function like double agents, mimicking estrogen in
one part of the body and acting against it in another. Tamoxifen acts like
estrogen by lowering blood cholesterol and slowing bone loss. It
neutralizes the effects of estrogen in the breast.
The 13,388 women in the study did not know whether they were taking
tamoxifen or the placebo. They are now being told and face the same
questions and considerations of risk that all women will face when
discussing the drug with their doctors.
Researchers, meanwhile, will continue trials of other Selective Estrogen
Response Modifiers on breast cancer, including more narrowly focused trials
on women with specific risk factors. |
