A new study finds Marin County isn't the only part of the Bay Area where breast cancer rates are higher than the state average.
Researchers with the California Breast Cancer Mapping Project say they've also found a higher rate of breast cancer -- defined as 10 to 20 percent above statewide average -- in parts of Alameda, Sonoma, Napa, Solano and Contra Costa Counties.
Researchers looked at breast cancer rates by census tract, a more targeted approach than other numbers which are collected county-wide.
“This is an opportunity for us to think about communities affected by breast cancer in new ways,” said Dr. Eric Roberts, of Oakland's Public Health Institute and principal investigator for the study [PDF]. “And one of them is that -- although no one argues that there isn't an excess of breast cancer in Marin County -- when you look at it this way, it appears more that Marin County is part of an extended area.”
The study also found portions of the South Bay have higher than average breast cancer rates. Those areas include communities in San Mateo County, northern Santa Clara and southern Alameda Counties.