(11-07-10) 95 percent of "preventive" mastectomies offer no benefit, study finds

by David Gutierrez, staff writer

A new study shows that the increasingly popular practice of "preventive
mastectomy" in non-cancerous breasts provides no benefit to the vast majority
of women.

"It's important for women to understand that, except for one subset of breast
cancer patients, they don't need to do this," said lead author Isabelle
Bedrosian of University of Texas M.D. Anderson Cancer Center. "Hopefully, it'll
reassure patients wondering if they should."

Approximately 40,000 women die from breast cancer in the United States each
year, and another 200,000 cases are diagnosed. Because cancer in one breast is
known to increase the risk of cancer recurrence in the other breast, doctors
are increasingly recommending that cancer survivors opt to have both breasts
removed as a "preventive" measure. And women are opting for it in huge numbers,
seeking the peace of mind that it is said to offer.

The number of preventive mastectomies in the United States increased two-and-a-
half-fold between 1998 and 2003. Today, 11 percent of all women undergoing a
mastectomy on a cancerous breast choose to have the non-cancerous breast
removed as well. Analysts have attributed this increase to more advanced
screening techniques that detect cancers smaller and earlier; popularization of
genetic screening and the idea that some genes may predispose families to
breast cancer; and wider public acceptance of plastic surgery combined with
advances in reconstructive technology.

Yet while it has been strongly established that elective mastectomy does
reduce the risk of breast-cancer recurrence, there has been no research to
suggest that it actually lengthens a woman's life span.

"We have not had real data to guide us," Bedrosian said. "We can't sit down
with a woman and say, 'If you do this, this is your expected benefit.' And when
we don't have those data, then biases become the big drivers of decision
making."

In the new study, published in the Journal of the National Cancer Institute,
Bedrosian and colleagues analyzed the records of 107,106 women in the National
Cancer Institute's Surveillance, Epidemiology and End Results registry. All the
women had undergone a mastectomy to treat breast cancer of Stage III or lower;
8,902 had chosen to have a healthy breast removed, as well.

After controlling for other risk factors, the researchers found only a small
difference in survival rates between women who had chosen to have two breasts
removed and women who had chosen to have only one removed. Upon further
analysis, they discovered that this benefit was only present in women under the
age of 50 with estrogen receptor-negative, early-stage tumors. In this group,
elective mastectomy increased the survival rate by 4.8 percent, amounting to
just under five lives saved for every 100 surgeries.

Elective mastectomy provided no survival benefit to women outside this
demographic.

The researchers believe that even when cancers recur, most women will not be
killed by them but will instead die of other causes first. Only in women whose
cancers lack estrogen receptors and who would otherwise have long lives ahead
of them does recurrence appear to pose a serious threat to survival.

The most effective breast cancer drugs on the market are those that lower the
body's production of estrogen, which fuels the growth of many cancers. Tumors
that lack estrogen receptors do not depend on the hormone for their growth,
however, meaning that women with these cancers cannot use the most effective
drugs and tend to have higher mortality rates.

Breast-cancer specialist Larry Norton of Memorial Sloan-Kettering Cancer
Center in New York City expressed skepticism about the study's methodology and
cautioned against doctors and patients giving it too much weight.

"This is an observational study, and hence it is impossible to control for
confounding variables," Norton said, "and should not be used for individual
clinical decisionmaking."

Norton admitted, however, that ethics make it impossible to perform a true
controlled study on the question, since such an experiment might end up
increasing cancer mortality in one group of participants.

Bedrosian disputed Norton's criticism, noting that the researchers used
rigorous statistical analysis and controlled well for interference from other
variables. She believes that the conclusions are, in fact, strong enough to
help women make better-informed decisions about elective mastectomy.

"We looked at this in multiple different ways, and we got the same answer
every time. And the results make good clinical sense. That adds another level
of reassurance," she said. "Our hope is that when women hear the numbers, they
will take a second look and decide not to go forward with a preventive
mastectomy [in their healthy breast] if it won't give them a survival benefit."

Victor Vogel, national vice president for research at the American Cancer
Society, said the results suggest that women should wait a full year before
going through with the removal of a healthy breast.

"In a younger woman with [estrogen receptor]-negative disease, an [elective}
mastectomy may be considered," he said. "In the vast majority of women older
than 50 with ER-positive disease, prudent waiting is probably the most
appropriate."

Bedrosian said that the point of the study was not to impose "a uniform
mandate" that women should never get the procedure, but that their decisions
must be well informed.

"This is still a decision to be made by the patient after talking with her
doctor," Bedrosian said.

"We hope this study helps women make better decisions [and] provides some
reassurance that perhaps a [preventive] mastectomy is not necessary, perhaps
overly aggressive and perhaps a bit too much."

Sources for this story include: http://www.chron.com/disp/story.mpl... http:
//www.medicalnewstoday.com/art... http://www.time.com/time/health/art....


Source: NaturalNews

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