Breast Cancer
A Reprieve from Chemo
By PAMELA DITTMER MCKUEN
Upon being told you have breast cancer, your blood turns arctic-cold. A
fierce terror grasps you in a strangle-hold. You are certain you will
die, and very soon. Your medical caretakers assure you that such is not
the case, there are therapies and treatments, and you will surely make
it through the process just fine. You want to believe, but you are
dubious. Your mind takes off again, zeroing in on the dreaded
chemotherapy. The terror tightens its grip.
Isn’t the uncertainty of a cancer diagnosis enough to bear without the indignities of chemo?
It’s quite possible. Tens of thousands of breast cancer patients,
mostly women, have gotten a reprieve in recent years. Their early-stage,
estrogen receptor-positive cancer qualified them for an innovative
diagnostic laboratory test, the OncotypeDX Breast Cancer Assay. This
test measures the likelihood of both the cancer’s return within 10 years
and the patient benefitting from chemotherapy in addition to
anti-hormonal drug therapy.
Lori Lockridge, 45, of Smithville, Mo., considers herself one of “the
lucky ones.” She was diagnosed in mid-April and has been commuting to
Cancer Treatment Centers of America at Midwestern Regional Medical
Center in Zion for her care. After a mastectomy in May, her OncotypeDX
score showed no need to undergo chemotherapy. “I have been blessed,” she
said. “The doctors say there’s no more cancer.”
OncotypeDX was developed by Genomic Health in Redwood City, Calif.,
and first made available in 2004. It works by examining a small sample
of the cancer, taken during a biopsy or surgery and preserved in a
paraffin block, and measuring the activity level of 21 relevant genes.
The result is expressed as a number between 0 and 100, called a
Recurrence Score. The lower the score, the less risk of recurrence and
less beneficial the chemotherapy. Scores below 18 are low, from 18 to 31
are intermediate, and above 31 are high.
By providing deeper insight into the cancer’s molecular biology,
which varies greatly from patient to patient, recurrence scores help
doctors make treatment recommendations. The scores are considered in
combination with other factors such as the patient’s age, tumor size and
grade, whether the cancer has spread to the lymph nodes and if so, how
far.
“The more we know about the particular disease and the patient, the
more we can tailor treatment to her situation,” said Cancer Treatment
Centers of America medical oncologist Dennis Citrin, M.D., PhD., who is
treating Lockridge. “Very subtle differences in the disease can have a
profound effect on our prognosis and treatment recommendations. Two
patients can have the same size tumor, the same node status, and one has
an Oncotype score of 6 and one has a score of 37. They will be treated
entirely differently.”
Although the major benefit of the test is that many women can
confidently forgo chemotherapy, high scores are valuable as well, by
providing confirmation that chemotherapy is necessary, he added.
Cindy Kleidon of Oak Park also was able to avoid chemotherapy. Three
years ago she underwent two lumpectomies followed by 10 sessions—twice
daily for five days—of balloon catheter radiation at Loyola University
Medical Center in Maywood. Her OncotypeDX score was low enough that the
radiation and drug therapy were sufficient to stave off her cancer.
“I know it’s not a guarantee, but it’s an indicator you can use
wisely,” said Kleidon, 65. “It was reassurance that we were heading in
the right direction. I’ve seen people really suffer from the side
effects of chemo. To me, it was a big relief not to have to go there.”
More than 200,000 new cases of breast cancer are diagnosed each year
in the United States. The most common form of the disease is estrogen
receptor-positive, which means the cancer cells are fueled by estrogen.
OncotypeDX is not the only multi-gene assay on the market, but it is the
mostly widely used. Others are Mammostrat Breast Cancer Test by
Clarient and MammaPrint by Agendia. The cost, far cheaper than
chemotherapy, is generally covered by insurance companies.
Not every patient is a good candidate for the test. And for some
patients, the test is more informative than for others. Those who score
in the intermediate range, for example, may not find the test
particularly helpful, perhaps raising more questions than it answers.
“There are those who will never accept chemotherapy, regardless of a
score, and so for them, the test should not be done,” said Kathy D.
Albain, M.D., professor of medicine at Loyola University Chicago Stritch
School of Medicine, and director of the Breast and Thoracic Oncology
Programs at Cardinal Bernardin Cancer Center in Maywood. “And vice
versa—some women want chemotherapy even if its benefit would be
marginal, so the test will have no added meaning.”
Patients also must understand that their scores assume they will receive at least five years of drug therapy, she added.
“It is absolutely critical they take it for the full five years,” said
Dr. Citrin, whose research into patient compliance shows that of those
who relapsed, more than half prematurely stopped taking the medication.
“It wasn’t the only reason for the relapse, but it is an important
factor.”
For the future, more and more is being learned about cancer behavior.
Genomic Health and other companies are refining and enlarging their
capabilities to include more cancer types and increasingly aggressive
forms of cancer. Initially only patients with no lymph node involvement
were eligible for OncotypeDX. The test has since become available to
select cases of node-positive cancers and ductal cancers in situ.
“Of every 100 women who receive chemotherapy for early-stage breast
cancer, only four will benefit,” said Emily Faucette, senior director of
corporate communications and spokesperson for Genomic Health. “Yet the
majority is treated with chemotherapy because there is no way to
identify who those four are. We haven’t precisely identified the four,
but we are getting closer.”
Now is an exciting time in breast cancer
biology research, said Dr. Albain, whose research focus is women with positive lymph nodes and their treatment.
“In node-positive breast cancer, the risk of relapse is generally
much greater, and all these women have been offered chemotherapy based
on its benefit to survival,” she said. “We may have been over-treating
some of these women.”
Genomic Health has also developed an OncotypeDX Colon Cancer Assay and is working on tests for prostate cancer.
“We believe there will be a day when there will be a test for all cancers,” said Faucette.
As for those patients who must endure chemotherapy, Dr. Citrin has
comforting news: It may not be as bad as you fear. Thanks to new
medications, the serious side effects such as nausea, vomiting and
infections, which were once inevitable and often debilitating, are far
less common today.
“Naturally, she should be apprehensive, but the fact is it is much
easier and better tolerated than it used to be,” he said.
Published: October 13, 2012
Issue: November 2012 Issue