(HealthDay News) -- Many women diagnosed with a precancerous breast lesion known
as ductal carcinoma in situ (DCIS) are highly anxious about their prognosis,
even though they face a low risk of a recurrence or of developing invasive
breast cancer, a new study finds.
"Many of these women are living as if they're waiting for the other shoe to
drop," said lead researcher Dr. Ann Partridge, an oncologist at the Dana-Farber
Cancer Institute and Brigham & Women's Hospital, in Boston.
Her team published the findings Feb. 12 in the online edition of the Journal of
the National Cancer Institute.
The study noted that 28 percent of the participants "believed that they had a
moderate or greater chance of DCIS spreading to other places in their bodies,
despite the fact that metastatic breast cancer actually occurs following a
diagnosis of DCIS less than 1 percent of the time."
DCIS involves abnormal cells in the lining of the breast duct that have not
spread outside the duct, according to the National Cancer Institute. In 2006,
DCIS accounted for more than 20 percent of all diagnoses linked to breast cancer
in the United States -- about 62,000 cases, the study reported.
The increasing percentage of DCIS diagnoses over the last 20 years or more has
been attributed to improved detection from the increasing use of screening
mammography, experts say.
But all too often, women are unnecessarily frightened by a DCIS diagnosis, said
the authors of the study, which involved almost 500 women newly diagnosed with
DCIS.
"In the complex treatment decision-making process, it is often possible to lose
sight of the fact that DCIS poses limited risks to a woman's overall mortality,"
the study authors noted.
Nevertheless, approximately 38 percent of those surveyed thought they had at
least a moderate risk of getting an invasive cancer over the next five years,
and 53 percent reported intrusive or avoidant thoughts about DCIS. That number
declined to 31 percent 18 months after diagnosis, the researchers said.
Among the 487 study participants who were newly diagnosed with DCIS, 34 percent
had undergone a mastectomy, 50 percent had radiation therapy, and 43 percent
reported taking tamoxifen to reduce their chances of breast cancer. The type of
treatment or combination varied by surgeon, hospital volume and geographic
region, the study explained.
"Although decision-making about treatment is complex, there is little doubt that
women will be limited in their ability to participate in informed
decision-making if they harbor gross misperceptions about the health risks they
face," the study authors said. Researchers found a "strong relationship between
distress and inaccurate risk perceptions," they added.
One of the difficulties of such measures of anxiety about DCIS is that the study
did not determine what these patients had learned from their physicians or from
other sources -- such as the Internet -- about DCIS, and how accurate that
information was, said Michael Stefanek, vice president of behavioral research
for the American Cancer Society.
The choice of treatment depends upon the characteristics of the patient and the
lesion, added Partridge, who is also an assistant professor of medicine at
Harvard Medical School. The dilemma posed by the prospect of under- or
over-treating DCIS is complicated by medicine's current inability to distinguish
between "good actors and bad actors" -- lesions that don't recur or go on to
become invasive breast cancer and those that do, she added.
Another expert agreed with that assessment.
Everyone would be more comfortable if there wasn't such a "big gray zone"
between what is normal tissue and what is invasive cancer, said Dr. H. Gilbert
Welch, a professor of medicine at Dartmouth Medical School and an expert on how
well health care works for patients. Welch argued that as mammography continues
to detect smaller and smaller DCIS lesions, there can be a tendency to
over-treat. He recommends that the diagnostic threshold for DCIS be raised to
doing biopsies on only lesions that measure 1 centimeter or greater in diameter.
"There is this ironic finding that women with this early precursor lesion may be
treated more aggressively than women with invasive breast cancer," he said.
"They may have mastectomies instead of just a lumpectomy. At some level we have
to say, 'Does this really make sense?'"
Another study in the same issue of JNCI suggests that medical science is winning
the war on breast cancer. The research, which involved nearly 5,000 breast
cancer patients, was led by the National Cancer Institute of Canada's Clinical
Trials Group. A total of 256 of the participants died during the four-year
study.
The researchers found that older women who had survived for at least five years
after a diagnosis of early stage breast cancer were most likely to die of causes
unrelated to their breast malignancy. In fact, 60 percent of these deaths were
not caused by breast cancer, the Canadian team found.
