Women who live in urban areas have denser breasts, making them more likely to develop breast cancer, according to a study presented recently at the annual meeting of the Radiological Society of North America (RSNA).

"Women living in cities need to pay more attention to having regular breast screening," said Nicholas M. Perry, mbbs, frcs, frcr, director of the London Breast Institute at the Princess Grace Hospital in London, UK. "Currently, women who live in urban areas are known to have lower attendance for breast screening programs than women in outlying areas."

Breast tissue in women may be fatty or glandular or a mixture of both. Women with more glandular breasts show denser tissue on a mammogram and are known to have nearly four times the risk of developing breast cancer than women with fatty breasts. Dr. Perry and colleagues set out to determine if there was a relationship between breast density and area of residence.

More Research Needed

The researchers analyzed digital mammograms of 972 women from urban, suburban, and rural areas. They discovered that women who lived in London had significantly denser breasts than those living outside the city. The risk of increased density was twice as great in the 45- to 54-year-old group. Age-specific analyses suggested that overall differences by area were more pronounced in women under age 50.

Dr. Perry cautioned that more research is needed to determine the precise reason for this phenomenon, taking into account lifestyle factors, stress, workplace, and other possible contributors, but he advised that all women maintain a recommended breast screening regimen, and that women with dense breasts be screened with digital mammography, which is more effective at detecting cancer in dense breast tissue.

"Regular breast screening with mammography saves lives," Dr. Perry said. "Access to breast screening for women living in cities must be prioritized."