Carcinoma of the cervix in Southwestern American indians: results of a cytologic detection program.

Age-specific detection rates for newly diagnosed in situ and invasive uterine cervical carcinoma were determined in a nine-year cytologic cancer detection program during which 34,700 Southwestern American Indian women and 46,200 medically indigent non-Indian women were screening for cervical cancer. For patients less than 35 years of age, cervical carcino a was found more frequently among Indians and Spanish-American Caucasians than among other Caucasian women. At ages 60 and older, the Indian cervical cancer rate was much higher than that of non-Indians. The detection rate for invasive cervical carcinoma among Indian patients is inversely related to the proportion screened at 30 years of age or older. Although at least 60% of Indian women 20 years old, and older, in the geographic area served by the detection program were screened for cervical cancer during the nine-year period, only 27% of those 50 years or older were screened. The age-related variation in screening percentage, in conjunction with the disproportionately large numbers of younger low-risk women, serves to explain the finding of significant invasive cervical carcinoma in an extensively screened population.