The influence of urbanization, age, ethnicity, and income on the early diagnosis of breast carcinoma - Opportunity for screening improvement

BACKGROUND. Because most risk factors for breast carcinoma are not readily amenable to primary prevention, and early diagnosis is a powerful prognosti c determinant, screening for the disease is crucial. Consequently, assessme nt of the progress and comprehensiveness of screening and other breast carc inoma early detection activities is important. The relative frequency of ea rly diagnosis may provide a useful indicator of such activities. Nationwide , time trends in the early diagnosis of breast carcinoma have been improvin g for decades, but not all population subgroups may have benefited equally. METHODS. Using 1994-1997 data from the California Cancer Registry (CCR), a review of diagnostic patterns of in situ and local stage breast carcinoma w as undertaken. For analytic purposes, the CCR includes 10 regional registri es and 36 county reporting groups. Three early diagnostic measures were des ignated, including in situ breast carcinoma with tumor size < 10 mm in grea test dimension, in situ breast carcinoma, and localized breast carcinoma wi th tumor size < 21 mm in greatest dimension. These are referred to hereinaf ter as early diagnosis breast carcinomas. RESULTS. The percentage of early diagnosis breast carcinomas differed marke dly by age, ethnicity, diagnosis year, and county of residence. Lower perce ntages of early diagnosis breast carcinomas were diagnosed in older women a ge 85 years. Hispanic women were diagnosed with lower levels of in situ bre ast carcinoma. Hispanic and black women were diagnosed with less localized breast tumors of small size. There was an increase in the percentage of ear ly diagnosis breast carcinomas over the 4-year observation period. Lower pe rcentages of early diagnosis breast carcinomas were reported for the nonurb an county/county groups, which were characterized by greater distances, low er population density, and lower household incomes. CONCLUSIONS. The authors conclude that elderly women, Hispanic and black wo men, and women who reside in nonurban areas should be targeted as high-prio rity subpopulations for mammographic screening. (C) 2001 American Cancer So ciety.