cancer, as in other areas of medicine, early detection can
save lives. But the screening tests used to find early tumors
also detect disease that would never cause problems —
disease you’ll die with but not from. Managing those cases
means giving potentially harmful treatment to patients who won’t
ductal carcinoma in situ, is the poster child of this dilemma.
Before routine mammograms, only about 1 percent of U.S. breast
cancer cases were DCIS. Now nearly 65,000 women a year —
about 22 percent of those with breast cancer — are diagnosed
also known as Stage 0 breast cancer, is not life-threatening,
and not all cases will progress to invasive cancer. But
because there is no reliable way to determine which ones will,
nearly all DCIS is surgically removed with a lumpectomy or
mastectomy (and sometimes the healthy breast is removed
prophylactically). Most DCIS patients also are offered
radiation and drugs.
many experts believe this simply is the price that must be
paid to save lives, an increasingly vocal minority are working
to find ways to reduce overdiagnosis and overtreatment,
especially of DCIS.
researchers got a big boost in August from a new study of more
than 100,000 women diagnosed with DCIS between 1988 and 2011.
The study, by Dr. Steven Narod of Women’s College Hospital
in Toronto, showed that DCIS patients had the same risk of
dying of breast cancer — just over 3 percent within 20 years
— as women in the general population. In other words, the
surgery, radiation and drugs didn’t make any difference for
the vast majority of patients.
minority — women under 35, African-Americans and those with
especially aggressive molecular features — had a
significantly higher chance of dying of breast cancer.
Ironically, they did so despite the aggressive treatment they
all the women were treated, so the Narod study could not show
if treatment was better than no treatment. But a separate
study published in June identified 1,169 DCIS patients who had
somehow escaped surgery and compared them with 56,053 women
who got the recommended operation. Breast cancer deaths were
slightly higher for women with intermediate- and high-grade
DCIS who did not have surgery, but there was no difference for
women with low-grade DCIS: Just over 1 percent of those women
had died of breast cancer after 10 years, whether they had had
surgery or not.
researchers, led by Dr. Yasuaki Sagara of Brigham and Women’s
Hospital in Boston, suggested watchful waiting for low-grade
DCIS. "From these results, we could consider recommending
a strategy of nonoperative management with active surveillance
similar to that used … in prostate cancer," they wrote.
doctors, however, are unwilling to change current practice
without more evidence that it’s safe. Dr. Otis Brawley,
chief medical officer at the American Cancer Society, has
called for a large clinical trial comparing mastectomy,
lumpectomy and no surgery for women with DCIS. At least two
such trials are underway in Europe.
U.S. centers already are allowing some low-risk DCIS patients
to skip surgery after being informed of the risks and
give people with low-grade DCIS the option of chemoprevention
or monitoring," said Dr. Laura Esserman, director of the
breast care center at the University of California-San
Francisco. Chemoprevention refers to taking a pill such as
tamoxifen for several years, which is known to halve the risk
of breast cancer in women at higher-than-average risk for the
is among those who consider DCIS a risk factor rather than a
disease that merits immediate treatment. She is a founder of
the Athena Breast Health Network, a collaboration between UCSF
and four other UC medical campuses. The network plans to
screen 150,000 California women for breast cancer, collect
information on their health and other risk factors, and begin
a decades-long tracking process that some have compared to the
Framingham Heart Study. The network will include a registry of
DCIS patients, many of whom Esserman expects will opt for
watchful waiting or chemoprevention rather than surgery.
lot of people are anxious to avoid unnecessary
treatment," she said.
also favors changing the name of the disease from DCIS to,
say, IDLE, for indolent lesion of epithelial origin —
something that doesn’t contain the word "cancer"
or "carcinoma." Studies have shown that many women
overestimate the danger of a DCIS diagnosis and that reframing
it as a high-risk condition rather than as cancer leads
patients to choose less aggressive treatments.
genomic test makes it somewhat easier for doctors and patients
to decide on a course of treatment. The DCIS Score rates the
chance that a given patient’s disease will recur or progress
to invasive cancer within 10 years. Those classified as low
risk are allowed to skip radiation, and in some cases they may
be offered the option of avoiding surgery too.
Shelley Hwang, chief of breast surgery at Duke Cancer
Institute in Durham, N.C., said she also sees DCIS patients
who would rather watch it than treat it. But she noted that
doctors don’t yet have conclusive proof that certain types
of DCIS can safely go untreated.
need to collect the data that will allow for clear risk
communication with patients so they can make their own
decisions about their care," she said. "The DCIS
Score, other risk-stratification factors, and the biospecimens
we get from the European studies will help us identify those