Changing cytologic detection rates for cervical intraepithelial neoplasia and invasive cancer in a population lacking...

The secular trends in the detection rates for cervical intraepithelial neoplasia (CIN) and invasive carcinoma were evaluated for a population lacking a mass screening program. For the period from 1980 through 1987, 185,659 Papanicolaou smears from 176,511 women were examined. The average annual age-adjusted detection rate for invasive cervical cancer declined from 3.7 x 10(-3) in 1980 to 1.4 x 10(-3) in 1987. The rate of cytologic findings consistent with CIN 3 and verified by histology increased from 0.7 x 10(-3) to 2.6 x 10(-3), and the rate of findings consistent with CIN 1 and CIN 2 increased from 4.3 x 10(-3) to 7.2 x 10(-3). The yield of Papanicolaou smear diagnoses consistent with CIN 3 was substantial (more than one case per 1,000) for women up to 60 years old, but was insignificant for older women.