MONDAY, May 11 (HealthDay News) -- Living in the city could lead to certain common cancers being diagnosed at much later stages of their development, new research has found.

A study of residents of Illinois finds that city dwellers are more likely to have doctors spot breast, colorectal, lung or prostate cancer later in the disease's progression than their peers residing in the suburbs or rural areas. The rates for these late-stage cancers were highest in Chicago, the most densely populated and urban of the areas in the analysis, and tapered off the more rural and sparse an area's population became, according to the findings, which were based on a review of the 1998 to 2002 Illinois State Cancer Registry.

"The concentration of health disadvantage in highly urbanized places emphasizes the need for more extensive urban-based cancer screening and education programs, especially programs targeted to the most vulnerable urban populations and neighborhoods," the study's authors, Sara L. McLafferty of the University of Illinois and Fahui Wang of Louisiana State University, wrote in their article, to be published in the June 15 print issue of the journal Cancer.

Age and race may account for much of the geographical difference in when colorectal and prostate cancers were diagnosed while they played a smaller role in the timing of breast cancer detection, the researchers noted. Urban blacks, for example, were much more likely to receive a late-stage diagnosis while older people living in rural areas were more likely to have their cancer diagnosed early because, it is speculated, this group is likely to visit doctors more often and receive age-related screenings for various diseases.

For lung cancer, the authors found that age and race did not explain the geographic disparities for stage of diagnosis, leading them to guess that other factors might be responsible.

More information

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