- 56 percent of women age 50 and older in 1994 had had a mammogram to detect breast cancer within the past 2 years,
- 77 percent of women age 18 and older in 1994 had had a Pap smear to detect cervical cancer within the past 3 years,
- 30 percent of people age 50 and older in 1992 had had a fecal occult blood test (FOBT) to detect colorectal cancer within the past 2 years, and
- 33 percent of people age 50 and older in 1992 had ever had a proctosigmoidoscopy to detect colorectal cancer (NCHS, 1997).
For those cancers for which effective screening tests exist, diagnosis at advanced stages among those eligible for screening suggests that tests are underused. Overall, 6 percent of breast cancers, 8 percent of cervical cancers, and 21 percent of colorectal cancers are diagnosed late (i.e., advanced) (Ries et al., 1997), but late stage at diagnosis is more common among some sociodemographic groups than others:
- People living in areas with high rates of poverty and unemployment are more likely to have their colorectal cancer diagnosed at a late stage than those living in other areas (Mandelblatt et al., 1996).
- Women living in poorer neighborhoods are more likely than women living in wealthier areas to have invasive, rather than localized, cervical cancer at diagnosis (Breen and Figueroa, 1996).
- African-American and other minority group members diagnosed with cancer are more likely to be diagnosed at advanced stages of disease than are whites (Farley and Flannery, 1989; Mandelblatt et al., 1991, 1996; Wells et al., 1992). For cervical cancer, this racial gap has increased over time despite greater use of Pap tests among African-American, compared to white women (Mitchell and McCormack, 1997).
- African-American and Hispanic women are more likely to have breast cancer diagnosed at late stages than white women, when setting of care, income, and education are controlled for (Mandelblatt et al., 1991).
- Women are more likely than men to have late-stage colorectal cancer at diagnosis (Mandelblatt et al., 1996).
Financial Barriers to Cancer Screening
Lack of health insurance is clearly linked to lower rates of cancer screening (Ayanian, 1993; Hedegaard et al., 1996; Katz and Hofer, 1994; Mickey et al., 1997) and to diagnosis at more advanced stages of disease (Figure 3.1). However, even in countries where health care coverage is universal, screening rates are not uniformly high. In Canada, for example, individuals with high compared to low household incomes are more likely to be screened for cancer (Katz and Hofer, 1994). Conversely, despite not having health insurance, 40 to 50 percent of uninsured women in the United States report that they have been screened for cervical and breast cancer (Hoffman, 1998).