Breast Care: an update
Wednesday, Oct.
24 - Oncology
(TRANSCRIPT - AS AIRED)
One of the fears of having breast cancer is the anticipation
of pain and suffering such as what a person has seen someone
else experience. Yet, in the last five to ten years advances
in early detection, minimally invasive surgeries, and improved
methods of radiation treatments and chemotherapies have
made it possible to have a very different course for the
disease, especially if it is found early.
"All the way from surgery to radiation oncology to
chemotherapy the changes have been incredible." (Medical
Oncologist Ronald Harris) "I think in a lot of ways
the focus of breast cancer has become how much benefit
are we going to get from that therapy and is it truly advantageous
to give it or receive it."
"Cancers are very unique and they behave differently.
That’s why we don’t have only one kind of chemotherapy
regime," (genetic counselor Luba Djurdjinovic). "And
usually as a cancer progresses and becomes more disorganized
it takes on new characteristics and it’s those characteristics
that either make it responsive to the chemotherapy or not.
So that’s why the earlier that you can find a cancer,
the more likely it’s going to respond to the traditional
therapies."
Dr. Ronald Harris is a medical oncologist at Broome Oncology
in Johnson City, New York.
"In early stage disease when a woman has
a tumor that is say one centimeter or two centimeters
the decision
of whether or not to give chemotherapy is based on estrogen
receptors expressed by the tumor, HER2/neu status of the
tumor, and prognostic factors such as the grade of the
tumor."
And what is meant by HER2/neu?
"HER2/neu is part of a group of receptors
on cells called tyrosine kinase receptors and they stimulate
pathways
in the cells that do multiple things, one of which is programmed
cell death. All cells in the body die at a certain interval;
they grow, they reproduce, and they die. Breast cancer
cells and cancer cells in general become immortal. They
turn off some of those programmed cell death or apoptotic
pathways. HER2/neu receptor stimulates production of a
protein and the drug Herceptin is a targeted therapy against
that protein. What it does is it causes the cells that
have turned off the pathway to turn the pathway back on."
And so it causes them to die off.
"It causes them to die off."
"Estrogen receptor positive; that means that the
tumor is partly fueled by estrogen and that’s true
I think for about 70% of women and about 80% of men," (male
breast cancer survivor Bob Ritter).
"What that means is that it can be treated
with drugs that block estrogen. Drugs like Tamoxifen
work for men.
There are newer drugs called aromatase inhibitors that
also block estrogen, so it gives doctors one more tool
to use."
"I think the discovery of Tamoxifen and Herceptin
has changed the way we treat breast cancer and has given
women a lot of hope for long lives surviving the breast
cancer." (Susan Kost, Director of the Breast Care
Center at Wilson Hospital in Binghamton, New York.) "Nationally
we’ve noticed that there may be a reason why women
are underusing mammography services because when they went
off estrogen replacement, hormone therapy, women may think,
OK, now I’m safe; I don’t have to worry about
breast cancer. And while we’ve seen some encouraging
signs that’s improved the deaths to breast cancer
women still should realize that isn’t the whole story."
"If a woman has a breast cancer and it’s
a high-risk breast cancer, doing an MRI of the breast
and
the opposite breast can indeed pick up more breast cancers
that would have been missed otherwise. So, finding additional
lesions which would affect surgery and possibly treatment
down the road becomes very important. So I think in that
way the advances of treatment are linked to the advances
of detection.
Could you talk a little bit about what kinds of new medications
are out to help lessen the side effects of chemotherapy?
"That’s an area that has truly improved greatly
over the last few years. The anti-emetics or anti-nausea
drugs have increased. They’ve discovered much more
precisely the mechanism of nausea due to chemotherapy and
in such have been able to develop drugs which target those
specific receptors. Currently I will tell you that the
days of a patient receiving chemotherapy with, unfortunately,
a bin in their lap have passed. Most patients, if they
do indeed develop nausea, we have a series of drugs that
we can go through and usually by the time we get to the
end of the list we’ve been able to control that.
So, in that respect, nausea has become a controllable side
effect."
Is the chemotherapy used today different, really, from
what was used five years ago?
"For the standard chemotherapy given in the adjuvent
setting or after surgery those drugs are mainly the same
that we use, although we use them differently. Something
called dose-dense chemotherapy has come around and what
we’ve discovered is that the time interval and the
intensity of chemotherapy can indeed change prognosis and
change outcome. So, routinely dose-dense chemotherapy is
given in a two-week fashion rather than a three-week fashion,
which is advantageous in a lot of ways. First of all, patients
tend to tolerate that regimen a little bit better. You
use growth-factor supports, drugs like Neulasta and Erythropoetin
or Procrit; patients are done with chemotherapy sooner
which is a big factor, especially when you’re dealing
with a young person or someone who’s working. There
are many drugs that have come around the corner in the
last five years, mainly used in metastatic breast cancer;
drugs such as Abraxane, or targeted therapies like Herceptin,
a new drug called Tykerb… and even a drug called
Avastin which has been notable for colon cancer. These
therapies are really, I think, the future direction."
What is different about those particular drugs?
"Those are targeted molecules. Now targeted
molecules have become I think of the future of oncology.
We are discovering
pathways that cancer cells become immortal and affecting
those pathways with a targeted therapy causes less side
effects, less toxicity generally because standard chemotherapy
does not differentiate cancer cells from normal cells."
And these are drugs that are on the market right now and
available?
"Yes. There are three drugs currently that
are used in breast cancer."
You mentioned growth factors earlier. What are they, and
what do they do?
"When I speak about growth factors generally there
are two classes that are used most commonly. One helps
your white blood cells grow; so it stimulates your bone
marrow stem cells to produce more white blood cells so
the time period that your white blood cell count is low
is lessened because specific white blood cells called neutrophils
are ones that are likened to the marines of our blood–they
go in first and they are your first line of defense against
infection. Unfortunately, chemotherapy does decrease those
white blood cells. And the second is Erythropoetin which
stimulates precursor red blood cells so that you make more
red blood cells to lessen the time that you are anemic. "
"A lot of people in the field will say that breast
cancers that are found very small, less than a centimeter,
are curable breast cancers. In other words, we catch them
early; we’re able to treat them early, and again,
depending on what their pathology shows, either through
surgery, lumpectomy, mastectomy, possibly radiation, possibly
chemo, possibly adjuvent therapies like Tamoxifen, we can
cure women. If women wait and don’t get yearly screening
mammography or don’t get clinical breast exams by
their provider, and they’re getting older and they’re
not doing these tests when we do finally find their cancers
through a lump it may be now over a centimeter; it may
have spread to the lymph nodes, making it more challenging
for us to treat and causing her to definitely have surgery,
radiation, and chemotherapy and then impacting her recurrence
rate. So, I think the biggest message for women is that
we do have the tools to prevent and cure breast cancer
by finding it early."
The "Breast Care: an Update" series is made
possible through a grant from the Susan G. Komen Foundation.
For WSKG, I’m Kathleen Cook.
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