Health: Fewer Breast Cancer Patients to Get Chemo

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Fewer Breast Cancer Patients to Get Chemo

 

By MARILYNN MARCHIONE

12/11/05 00:43

 

SAN ANTONIO (AP) - For years, doctors have known exactly what to do with

breast cancer patients like Eva Ossorio: Poison them. Blasting women

with toxic chemicals was considered the best way to save their lives.

The bigger the cancer or the more it had spread, the more vile liquid

doctors pumped into their veins to try to kill it. But there's been a

sea change in the last year.

 

Guidelines recently adopted in Europe and similar ones unveiled this

weekend at a conference in Texas will result in far fewer women getting

chemotherapy in the future.

 

The new advice calls for choosing a treatment based on each woman's

particular type of tumor.

 

" In the past, we made all decisions based on how big the tumor was and

whether the lymph nodes were involved. If you had a lot of cancer, you

got treated one way, and if you had a little cancer, you got treated

another way, " said Dr. Eric Winer of the Dana-Farber Cancer Center in

Boston.

 

Under the new rules, hormone status - whether a tumor's growth depends

on estrogen or progesterone - becomes the single most important factor

in picking treatment.

 

That is why Ossorio, a 62-year-old nurse in San Antonio, last week was

started on a hormone blocker rather than the chemo she formerly would

have been given for her relatively large tumor. She was relieved.

 

" I don't care if I die tomorrow. I decided I didn't want chemotherapy, "

she said.

 

Women have reason to dread it. Chemo is a sledgehammer, killing all

rapidly dividing cells whether they are out-of-control cancerous ones or

healthy ones that naturally grow quickly, like those lining the mouth

and stomach. That's why chemo causes hair loss, nausea and mouth sores.

 

But the worst part is, it only helps about 15 percent of those who get

it after the usual surgery to remove their tumors. Roughly 25 percent

get worse despite chemo. A whopping 60 percent would have been fine with

hormones alone.

 

" For the vast majority of patients, we probably overtreat, " said Dr.

William Gradishar of Northwestern University in Chicago.

 

" It's not that chemotherapy is not of value, it's that the value is

smaller in women with hormone-driven disease, " said Dr. Robert Carlson,

a Stanford University physician who led the U.S. guideline-writing

group. " We're trying to determine if the benefit is so small that we

should not be recommending chemotherapy. "

 

Several developments in recent years help doctors pick who really needs it.

 

First is the realization that breast cancers have different causes,

arise from different types of cells, are driven by different genes, and

tend to be different in women before or after menopause.

 

" Breast cancer must be understood as an umbrella of diseases, " said Dr.

Antonio Wolff of Johns Hopkins Medical Institute in Baltimore.

 

For example, three-fourths of postmenopausal women have tumors fueled by

estrogen, called ER-positive disease. Drugs that block this hormone,

like tamoxifen and a newer class of medications called aromatase

inhibitors, work against those cancers - whether they have spread to

lymph nodes or not.

 

On the other hand, women before menopause often have tumors that are

ER-negative and orchestrated by bad genes. Hormones don't help in that

case; these women benefit most from chemotherapy.

 

If hormone drugs are ball-peen hammers compared to chemotherapy, a

medication like Herceptin is an even more refined tool. It targets the

one-fourth of breast cancers that have too much of a protein on cell

surfaces called HER-2 and leaves healthy cells alone.

 

A woman's HER-2 status is the next factor doctors will consider, after

hormone status, in choosing treatments under the new guidelines.

 

You can see the possibilities: half of HER-2 tumors are ER-positive, but

only 10 percent of ER-positive tumors are HER-2-negative.

 

These aren't black-and-white distinctions, either. Tumors can be weakly

ER-positive or negative; same thing for HER-2.

 

New high-tech lab tests help doctors sort it out. They measure the

activity of dozens of genes and reveal which ones are most active and

what treatments would work best.

 

One such test, Oncotype DX, has found its way into more and more

doctors' offices since presentations at the Texas cancer meeting last

year showed its ability to predict which women benefit from tamoxifen

and which do best on chemo.

 

Ossorio's doctor ordered the test because she thought it would convince

Ossorio to have chemo. Surprisingly, it revealed chemo was very unlikely

to help.

 

The test is expensive - $3,400 - but many insurers cover it because it

often prevents even more costly and unnecessary chemo, as it did for

Ossorio.

 

Dr. Larry Norton, breast cancer chief at Memorial Sloan-Kettering Cancer

Center in New York, uses it when situations are complex and treatment

choices aren't obvious. He compares it to lab tests that pinpoint a germ

so the right antibiotic can be prescribed.

 

" In the old days, people just said 'pneumonia.' Now we say 'what

organism?' and that lets us identify how to treat the disease, " he said.

 

But relying on factors like hormone and HER-2 status makes the accuracy

of lab tests a life-or-death matter. Doctors warn about the wide

variation in the quality of such tests, whether low- or high-tech.

 

" The right (test) is the one that is done right, " not which type of test

is chosen, Wolff told doctors at the Texas meeting who had come to learn

about the U.S. guidelines. The new guidance was developed by the

National Comprehensive Cancer Network, a group of leading cancer

treatment centers, in cooperation with the American Cancer Society.

 

They soon will be published and are available now on the network's web

site, http://www.nccn.org

 

On the Net:

 

San Antonio Breast Cancer meeting: www.sabcs.org

 

U.S. cancer guidelines: www.nccn.org

 

European guidelines:

www.breastcancersource.com/breastcancersourceHCP/9678-13596-7-0-0.as px

 

and www.oncoconferences.ch/2005/Short-Conference-Summary-PBC-05.pdf

 

American Cancer Society: www.cancer.org

 

National Cancer Institute: www.cancer.gov

 

12/11/05 00:43

 

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