CHICAGO--A pair of large-scale clinical investigations reported
at the annual meeting of the Radiological Society of North America
is renewing the controversy over the need to perform mammography
in young women.
Data from the Screening Mammography Program of British Columbia
(SMPBC) indicated that 15% of the cancers detected in 150,147
asymptomatic women who had a mammographic examination in a 5-year
period were in women under age 50. Mammography detected cancer
in an early, curable stage in approximately 87% of these women,
and even found cancer in dense breast tissue.
"It usually is more difficult to detect cancer in dense tissue
than fatty tissue. However, we had increased cancer detection
rates in young women with dense tissue because many of the cancers
showed up as calcium deposits," said Linda Warren Burhenne,
MD, executive director of the SMPBC, the largest mammographic
screening program in North America.
28% of Cases Under Age 50
A 3-year study of 3,159 women who had breast biopsies at Thomas
Jefferson University Hospital, Philadelphia, found that 28% of
851 women with breast cancer were under age 50, and 46% of the
tumors detected in the younger women were nonpalpable.
"Breast cancer tumors that are smaller, nonpalpable, and
less aggressive histologically have better prognosis," said
Emily Conant, MD, assistant professor of radiology, Thomas Jefferson
Based on the data from their studies, Drs. Warren Burhenne and
Conant both advocate regular mass mammographic screening of young
women. Although the incidence of breast cancer in British Columbia
is higher than that in any of the other Canadian provinces, mortality
from breast cancer is the lowest. "We believe this is occurring
because nearly 40% of all the eligible women in British Columbia
are having annual mammograms," Dr. Warren Burhenne said.