A trend analysis of breast cancer incidence rates in the United States from 2000 to 2009 shows a recent increase.

Recent reports have shown that the breast cancer incidence rate in the US stabilized after a sharp reduction in 2002 and 2003. It is important to continue monitoring breast cancer incidence rates according to age group, race/ethnicity, estrogen receptor (ER) status, and tumor stage. Age-standardized breast cancer incidence rates were calculated using data from the surveillance, epidemiology, and end results 18 registries from 2000 to 2009, for 677,774 female breast cancer patients aged 20 and above. Jointpoint regression models were used to fit a series of joined straight lines on a log scale to annual age-standardized rates. The incidence rates of all breast cancer significantly increased for non-Hispanic blacks from 2005 to 2009 (annual percentage change, APC = 2.0 %, p = 0.01) and Asian/Pacific Islanders from 2000 to 2009 (APC = 1.2 %, p = 0.02). Since 2004, incidence rates in women aged 40-49 years significantly increased for most racial/ethnic groups (overall APC = 1.1 %, p = 0.001). The incidence rate of carcinoma in situ significantly increased in all racial/ethnic groups, with an APC range from 2.3 to 3.0 % (p < 0.005). The localized breast cancer incidence significantly increased in non-Hispanic blacks (APC = 1.3 %, p = 0.004) and Asians (APC = 1.2 %, p = 0.03). ER-positive breast cancer significantly increased in almost all age/race sub-groups after 2005 (APC by race: non-Hispanic whites 1.5 %, non-Hispanic blacks 4.3 %, Asian/Pacific Islanders 1.7 %, and Hispanics 1.8 %; all p values <0.05), while ER-negative breast cancer decreased in most sub-groups (APC by race: non-Hispanic whites-3.9 %, non-Hispanic blacks-3.7 %, Asian/Pacific Islanders-1.5 %, and Hispanics-4.3 %; all p values <0.05). Recently the incidence of breast cancer appears to be increasing in certain subgroups, including ER-positive, early-stage breast cancers, in particular among non-Hispanic blacks and Asian/Pacific Islanders. Further studies are warranted to examine possible reasons for these changes, such as changes in mammography screening methods and risk factors prevalence.