Cancer screening estimates for U.S. metropolitan areas. 
To provide estimates of breast, cervical, and colorectal cancer screening for metropolitan areas in the United States.  Behavioral Risk Factor Surveillance System (BRFSS) data from 1997 to 1999 were reweighted and analyzed for 69 U.S. metropolitan areas for the receipt of a Papanicolaou (Pap) test (ages > or =18 years); mammography (ages > or =40 years); fecal occult blood testing and sigmoidoscopy (ages > or =50 years).  Stratified analyses by demographics were performed for 25 metropolitan areas with populations of > or =1.5 million.  Metropolitan estimates ranged from 64.6% to 82.0% for mammography and from 77.2% to 91.7% for Pap tests.  There was much greater variability in estimates for colorectal cancer screening, with a 3.6-fold difference in the range of estimates for fecal occult blood testing (9.9% to 35.2%) and a 2.5-fold difference for sigmoidoscopy (17.3% to 43.3%).  In the 25 largest areas, prevalence of cancer screening was generally lower for persons with a high school education or less and for those without health insurance.  Compared with women aged 50 to 64 years, mammography estimates were lower for women aged 40 to 49 years in 13 of the 25 metropolitan areas.  Pap testing was less common among women aged > or =65 years, and colorectal cancer screening was less common for persons aged 50 to 64 years.  Estimates of cancer screening varied substantially across metropolitan areas.  Increased efforts to improve cancer screening are needed in many urban areas, especially for colorectal cancer screening.  The BRFSS is a useful, inexpensive, and timely resource for providing metropolitan-area cancer screening estimates and may be used in the future to guide local or county-level screening efforts.