Re: doctors may eventually be able to identify women who do not need chemotherapy

Um, the correct answer would be all of them.

J wrote:
<http://www.nytimes.com/2006/04/11/health/11cnd-cancer.html?hp&ex=1144814400&en=7091deadab200aaf&ei=5094&partner=homepage>

New Breast Cancer Studies Yield Surprises
By GINA KOLATA
Published: April 11, 2006

Two important studies being published today challenge conventional
thoughts about treating and avoiding breast cancer.

One suggests that doctors may eventually be able to identify women who do
not need chemotherapy. The others says that women who have had
hysterectomies can take estrogen to relieve symptoms of menopause without
increasing their risk of breast cancer.

The first study, published in the Journal of the American Medical
Association, indicates that many of the 70 percent of women whose cancers
are fed by estrogen get so much benefit from estrogen-blocking hormonal
therapy that chemotherapy adds little if anything more.

The caveat, though, is that there is as yet no reliable way to identify
the women who may not need chemotherapy from those who would be helped by
it.

Currently, guidelines call for women to get chemotherapy if their tumors
are of a certain size.

Dr. Eric P. Winer, an author of the paper who is director of the Breast
Oncology Center at the Dana-Farber Cancer Institute in Boston, explained
the guidelines' message: "Virtually every woman with a tumor larger than a
centimeter should get chemotherapy. Period. End of story."

But, he said, over the past couple of years, "that question has been
reopened in a major way." The new study, he added, is part of the
reexamination.

The study involved an analysis of data from three large clinical trials
that tested different chemotherapy regimens. One gave two standard drugs
with or without a third chemotherapy drug, paclitaxel. Another asked if it
was better to give chemotherapy drugs in low, moderate, or high doses and
the third asked whether it was better to give the drugs more intensely, in
two week cycles, or whether three week cycles were best. The women also
had surgery and radiation as appropriate but the studies focused on the
effects of chemotherapy.

The analysis, by a group of leading breast cancer researchers, led by
Donald Berry, a statistician at M.D. Anderson Cancer Center, looked at the
studies' data and asked whether some women were more likely to benefit
from chemotherapy than others.

The conclusion was that even though the studies involved very different
chemotherapy regimens, one variable always stood out - whether a woman's
cancer was estrogen receptor positive, meaning it was fed by estrogen, or
estrogen receptor negative, meaning it was impervious to estrogen's
effects.

"All the benefits were in the estrogen receptor negatives," Dr. Berry
said.

"Then I asked, What is going on here?" he continued. The answer, he and
his colleagues report in the new paper, is that hormone therapies with
drugs like tamoxifen that starve cancers of estrogen are so powerful -
reducing the death rate by 30 percent in women with estrogen receptor
positive tumors - that chemotherapy helps those women much less than it
helps women with estrogen receptor negative tumors.

On average, the researchers report, a women whose cancer does not respond
to estrogen has a 23 percent greater chance of surviving five years,
disease free, if she has chemotherapy. For a woman whose cancer is fed by
estrogen, chemotherapy increases her chance of surviving that long by 7
percent.

"To me, what that means is that as we approach decisions about
chemotherapy, we have to think very differently for women with estrogen
receptor negative cancers than for those with estrogen receptor positive
cancers," Dr. Winer said.

"For the estrogen receptor negatives, there is a very dramatic improvement
with chemotherapy," Dr. Winer said. "The vast majority of those women,
except for those with the tiniest tumors or those with other health
problems who would be expected to live only a few more years, should
receive a course of chemotherapy."

As for those with tumors that are fueled by estrogen, however, "we have a
big challenge," Dr. Winer said. "We know that on average the benefit is
less but there are clearly women who benefit," from chemotherapy, he
explained. "The challenge is to identify them"

There are tests of how sensitive a tumor is to estrogen, but, Dr. Winer
said, they "are not as reliable as we all would like." There also is a
gene test, the Genomic Health/NSABP recurrence score, that looks at 21
genes and is correlated with a tumor's response to estrogen and response
to chemotherapy. But, Dr. Winer said, "it too is not ready for general
use," to determine which patients with estrogen-fueled cancer could
actually forgo chemotherapy.

For now, says Dr. Clifford Hudis, a co-author of the paper and chief of
the breast cancer service at Memorial Sloan Kettering Cancer Center in New
York, cancer treatment recommendations should not change. The new results,
Dr. Hudis said, are "hypothesis generating" and call out for further
research.

Doctors need reliable tests of tumors with estrogen receptors and they
need studies to show that those tests can pick out the women whose will do
just as well with just hormonal treatments to starve tumors of estrogen as
they will with hormonal treatments and chemotherapy.

The field is in a transition period, Dr. Winer said, adding that the
question for cancer specialists and women with estrogen receptor positive
tumors is how far to push the envelope. Do you take a chance that the
currently available tests will tell you that you will or will not respond
to chemotherapy? Or you decide that since, on average, women with
estrogen-fed tumors gain a small survival benefit from chemotherapy, you
cannot forgo the treatment?

"There will be patients who say, 'Overall, there is a small benefit for
patients in my situation so unless you can tell me there is no benefit, I
want chemotherapy,' " Dr. Winer said. "And there will be others who say,
'The overall benefit is small to moderate and if you can't tell me that I
will be the one to benefit from chemotherapy, I will forgo it."'

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