Radiation
and Chemotherapy for High-Risk Breast Cancer
Adding
radiation therapy to chemotherapy improves survival in patients
with high-risk breast cancer who have had a modified radical
or full mastectomy, say researchers in the Journal
of the National Cancer Institute.
The
new report includes two decades of followup on patients who
began treatment from 1979 through 1986.
"We
have confirmed with even more significance that, as time goes
on, the survival difference is even more significant," says
Dr. Joseph Ragaz, director of oncology at the McGill University
Health Center in Montreal and the lead author of the new research.
In
the original trial, known as the British Columbia randomized
radiation trial, 318 breast cancer patients were randomly assigned
to either receive radiation therapy after a modified radical
mastectomy and chemotherapy or get no additional therapy.
In
an earlier follow-up, encompassing 15 years, radiation therapy
was associated with a significant improvement in breast cancer
survival but a borderline statically significant improvement
in overall survival.
The
20-year follow-up found improvement in all aspects: the addition
of radiation therapy resulted in a 32 percent reduction in breast
cancer deaths and a 27 percent reduction in overall deaths compared
to the use of just chemotherapy after surgery.
All
the patients in the study had high-risk breast cancer, defined
as having at least four lymph nodes involved, Dr. Ragaz notes.
And
while the study did not cover the value of radiation therapy
for lumpectomy patients, Dr. Ragaz adds, "Our data is acceptable
enough to say, whether the breast is left or not, [if] the patient
is high risk . . . . radiation should be given to the lymph
nodes and the breast to improve survival."
Dr.
Timothy Whelan, an associate professor of medicine at McMaster
University in Hamilton, Ontario, writes in an editorial, "The
study is really good news. It confirms findings from years ago.
This study shows if radiation is given carefully and to the
right group of patients, it can be a win-win situation."
In
previous research, radiation has been associated with an increase
in some instances of heart disease, but those studies involved
radiation given to the heart area, Dr. Whelan says.
"Now,
with newer techniques, we can avoid radiation to the heart pretty
much entirely," he explains.
In
the study period reported by Dr. Ragaz, the radiation involved
targeting the heart area but the benefits persisted, he says.
What
is yet to be studied, Dr. Whelan adds, is whether women at moderate
risk of recurrence should also get radiation therapy.
Dr.
Ragaz is now studying whether radiation should also be used
in patients with fewer lymph nodes involved.
Always
consult your physician for more information.
|
Radiation
therapy is a process that precisely sends high levels of radiation
directly to the cancer cells.
Radiation
done after surgery can kill cancer cells that may not be seen
during surgery.
Radiation
may also be used:
-
prior to surgery to shrink
the tumor
-
in combination with chemotherapy
-
as a palliative treatment
(therapy that relieves symptoms, such as pain, but does
not alter the course of the disease)
There
are two ways to deliver radiation therapy. However, external
radiation is the usual type that is used for treatment of breast
cancer.
External
Radiation
(external beam therapy)
This treatment precisely sends high levels of radiation
directly to the cancer cells. The machine is controlled by the
radiation therapist.
Since
radiation is used to kill cancer cells and to shrink tumors,
special shields may be used to protect the tissue surrounding
the treatment area. Radiation treatments are painless and usually
last a few minutes.
Internal
Radiation
(brachytherapy, implant radiation)
This radiation is given inside the body as close to the cancer
as possible. Substances that produce radiation, called radioisotopes,
may be implanted directly into the breast tumor.
Internal
radiation involves giving a higher dose of radiation in a shorter
time span than with external radiation. Internal radiation for
breast cancer is currently being studied and is considered experimental.
A
radiation oncologist will plan your radiation treatment based
on your medical history, a physical examination, pathology and
laboratory reports, and previous mammograms and surgeries.
Your
chest area will be marked with ink that must stay on your skin
for the course of your treatments. These markings assure that
the radiation will be given to the exact area requiring treatment.
Side
effects of radiation therapy:
As each woman's individual medical profile and diagnosis is
different, so is her reaction to treatment. Side effects may
be severe, mild, or absent.
Be
sure to discuss with your cancer care team any/all possible
side effects of treatment before the treatment begins.
Possible
side effects that may occur during or following radiation for
breast cancer include:
-
fatigue (especially during
the later weeks of treatment)
-
skin problems in the treated
area, including soreness, itching, peeling, and/or redness.
Toward the end of treatment, the skin may become moist
and weepy.
-
decreased sensation in the
breast tissue or under the arm
In
most cases, the effects of radiation on the skin are temporary
and the skin involved in the treated area will heal upon completion
of treatment.
Always
consult your physician for more information. |
