[Mb-civic] A Boost For Breast Cancer Prevention - Washington Post

[William Swiggard]

A Boost For Breast Cancer Prevention
Osteoporosis Drug Lowers Risk With Fewer Side Effects

By Rob Stein
Washington Post Staff Writer
Tuesday, April 18, 2006; A01

A drug used to prevent bones from thinning also offers millions of older 
women a powerful way to protect themselves against breast cancer, a 
large government-sponsored study has found.

The study of nearly 20,000 postmenopausal women found that raloxifene 
reduces their chance of developing breast cancer as effectively as 
tamoxifen, the only drug previously shown to reduce the risk, but is 
less likely to cause serious side effects such as uterine cancer and 
blood clots.

The findings indicate that raloxifene, sold under the brand name Evista, 
is a safer alternative for the estimated 9 million postmenopausal U.S. 
women at increased risk for breast cancer, experts said.

"This is good news for women," said Leslie Ford of the National Cancer 
Institute, which sponsored the $88 million study and released the 
preliminary findings early because of their public health implications. 
"Women now have a new option."

Because an estimated 500,000 women use raloxifene to reduce the risk of 
osteoporosis, many will be more comfortable using it for breast cancer 
protection, several experts predicted.

"It's terrific," said Susan Love, a breast cancer expert at the 
University of California at Los Angeles. "This gives us another drug 
that we can use to prevent breast cancer that is less risky than the 
only other drug we had."

Several experts, however, urged caution, saying that the advantage of 
raloxifene remains unclear and that more research is needed to prove the 
drug reduced the overall risk over longer periods.

"We need to understand who would be most likely to benefit. All drugs 
have side effects. We want to avoid exposing women to powerful drugs 
unnecessarily," said Carolina Hinestrosa of the National Breast Cancer 
Coalition, an advocacy group.

Eli Lilly and Co. said it would ask the Food and Drug Administration to 
approve Evista for breast cancer prevention in postmenopausal women, but 
doctors are free to prescribe it for that purpose immediately because 
the drug is already marketed for osteoporosis.

"I suspect a lot more women will be willing to take this drug," said 
Patrick Borgen of Memorial Sloan-Kettering Cancer Center in New York. 
"People see tamoxifen as a cancer treatment drug. When it comes to 
prevention, people don't want to be thought of as patients. This may be 
seen much more as a prevention drug."

Breast cancer strikes more than 211,000 U.S. women each year and kills 
more than 40,000, making it the leading cause of cancer and 
second-leading cancer killer among women.

Tamoxifen and a new class of drugs known as aromatase inhibitors can 
reduce the risk of breast cancer's recurrence, but tamoxifen is the only 
drug that had been shown to prevent tumors in the first place, cutting 
the chances by about half. It is not widely used for preventing primary 
tumors, though, mainly because it carries an increased risk of uterine 
cancer and blood clots.

Raloxifene works similarly to tamoxifen by blocking the effects of the 
hormone estrogen on breast tissue. To see whether it might be as 
effective as tamoxifen at reducing the risk of primary breast cancer, 
researchers gave 19,747 postmenopausal women either 60 milligrams of 
raloxifene or 20 milligrams of tamoxifen every day for five years. All 
were at increased risk of breast cancer because of their age, family 
history or other reasons. The study is the largest to test any drug for 
breast cancer prevention.

A preliminary analysis of the data found no difference in the number of 
invasive breast cancers in the two groups, indicating that raloxifene 
also cuts the risk by 50 percent. There were 167 invasive cancers in the 
raloxifene group and 163 in the tamoxifen group. About 320 women in each 
group would have been expected to develop breast cancer.

But the women taking raloxifene experienced 36 percent fewer uterine 
cancers (23 vs. 36) and 29 percent fewer blood clots (100 vs. 141). They 
were also less likely to develop cataracts.

"Raloxifene clearly has less toxicity and fewer side effects," said D. 
Lawrence Wickerham of the National Surgical Adjuvant Breast and Bowel 
Project in Pittsburgh, which led the study. "It's very exciting."

The findings, which do not necessarily apply to premenopausal women, 
will be published in a peer-reviewed journal and presented at a meeting 
of the American Society of Clinical Oncology. They were released early 
to give the participants a chance to switch drugs and to alert the 
public about the findings, officials said.

Although other researchers agreed the findings are promising, some were 
more cautious. Several noted, for example, that the study found that 
women taking raloxifene had no decrease in risk for very early forms of 
breast cancer known as ductal carcinoma in situ and lobular carcinoma in 
situ.

"If you want to show a long-term reduction in invasive cancer, you need 
to show a decrease in pre-invasive cancer," said Paul Goss of Harvard 
Medical School.

Others noted that it remains unclear whether the overall net benefit of 
the drug outweighs the net risks.

"I would call this a modest advance," said Carol Fabian of the 
University of Kansas.

But the researchers who conducted the study estimated that if every 
eligible woman used the drug, it would protect more than 2 million from 
developing life-threatening health problems.

"This gives women a real choice for reducing their risk for two of the 
major causes of morbidity and mortality as they age -- osteoporosis and 
breast cancer," Ford said.

Raloxifene costs about $75 for a one-month supply; tamoxifen costs about 
$100 for the same amount, officials said.

http://www.washingtonpost.com/wp-dyn/content/article/2006/04/17/AR2006041701178.html?referrer=email
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.islandlists.com/pipermail/mb-civic/attachments/20060418/4ee993ad/attachment.htm