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Male Breast Cancer on the Rise Among Senior Citizens
Average Age of Discovery is 67 Versus 62 for Women
May 24, 2004 - The rate of male breast cancer is on
the rise and the disease in men is usually detected when men are older,
the tumors are bigger, have spread and may be more aggressive, compared
to diagnosis of the disease in women, concludes the largest study ever
conducted of male breast cancer.
The findings, published today in the online edition
CANCER and will appear in the July 1 print issue of the
publication, suggest both that breast cancer in men may have some
important biological differences from the female disease, and that men
are seemingly less aware than they should be that they can develop
breast cancer.
According to the study's lead investigator, Sharon
H. Giordano, M.D., assistant professor in the Department of Breast
Medical Oncology at The University of Texas M. D. Anderson Cancer
Center, the incidence of the disease has increased significantly in the
last 25 years, from .86 to 1.08 per 100,000 men.
They analyzed SEER data from 1973 through 1998 on
2,524 cases of male breast cancer and 380,856 cases of female breast
cancer. Compared to female patients, the investigators found that male
patients were significantly older when diagnosed - 67 years versus 62
years of age. They were also more likely to have later stage disease and
had more spread of the cancer to their lymph nodes.
"It's perhaps ironic that tumors in men are easier
to feel than they are in women, yet the disease is being discovered at a
later stage in men than in women," says Giordano.
One reason for such a late diagnosis may be that
men assume they are experiencing a benign condition called gynecomastia,
or atypical growth of breast tissue that affects about a third of males
at some point in their lives, says Giordano. The condition, common in
adolescent boys, can come and go over a man's lifetime and "men may
think new growth of breast tissue is just another occurrence of this
condition," she explains.
Furthermore, Giordano and the researchers found
that the most common types of cancers in men were invasive ductal
carcinoma, found in 93.4 percent of the men, and papillary carcinoma,
which accounted for 2.6 percent of the cases.
Yet despite these differences, five-year, 10-year
and median survival were not different between men and women,
investigators say.
"Male breast cancer is rare, accounting for less
than one percent of all breast cancer, or about 1,600 new cases in the
United States in 2004. While, it's not as high of an increase in cases
as that in women, men should be alert to the possibility that the
disease could affect them," says Giordano.
Because breast cancer in men is rare, little is
known about how it differs from breast cancer in women and how it should
be best treated. To assess dissimilarity, Giordano and her M. D.
Anderson colleagues used information from a National Cancer Institute
database called SEER (Surveillance, Epidemiology, and End Results),
which is the authoritative source of information on cancer incidence and
survival in the United States.
Also of interest to the researchers was the finding
that male patients are more likely than female patients to have estrogen
receptor-positive tumors.
"We are not sure why this is so, but it may
indicate some important differences in tumor biology," she says. "In
addition, this implies that use of tamoxifen in men may be as beneficial
as it is to many women," says Giordano.
"Now that we have a clearer understanding of the
biology of breast cancer in men, further research is needed to determine
the optimal treatment for men," she says.
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