In this study we evaluated CDP: EWC, a large public health screening program for low-income women to determine whether the ASC-H term, introduced in the 2001 revision to the Bethesda System, has facilitated the detection of the most serious precancerous cervical lesions such as CIN-II-III/CIS, including accuracy of detection and minimizing diagnostic delays. Pap test and biopsy data from the period 2003-2006 were compared with those from 1995-1999, and included analysis of a subset of rarely and never-screened for each study period. More ASC-H Pap tests were followed by CIN-II+ biopsies (20%) than ASCUS Pap tests (5%). Thirteen percent of ASC-H showed CIN-III/CIS on follow-up biopsy. Following the introduction of ASC-H, negative and LSIL Pap tests followed by CIN-III/CIS biopsies decreased from 5.6% to 0.37% and 9.2% to 4.4%, respectively. Fewer CIN-III/CIS cases were preceded by Pap tests with negative and ASCUS results in 2003-2005 as compared with 1995-1999. The number of days from screening to diagnosis for women aged 25-39 years with ASC-H Pap test results (58 days) was less than for ASCUS results (78 days) for the current study period. In this high-risk multi-ethnic population, ASC-H more effectively communicates equivocal findings likely to represent HSIL leading to more rapid follow-up. The incidence of CIN-II or CIN-III/CIS following ASC-H Pap tests is lower than generally appreciated for this population, including for rarely or never-screened high-risk women. Fewer CIN-III/CIS lesions were detected following negative and ASCUS Pap results. Compliance with follow-up is less than ideal for this population.

BACKGROUND:This study focuses on age, race/ethnicity and regular cervical cancer screening of medically underserved Latina and non-Latina women enrolled in California's Cancer Detection Programs: Every Woman Counts (CDP: EWC). METHODS:Data from a cohort of women were evaluated for regularity of screening and ethnicity utilizing multi-category logistic regression models to investigate Pap test and biopsy results. RESULTS:There was no statistically significant difference among medically underserved Latina or non-Latina women in Pap test result and stage of cervical cancer after controlling for age and screening regularity. Rarely/never Pap-tested women were more likely to have 'SIL/ASC' (odds ratio=1.19; 95% confidence interval=1.08, 1.31) compared to women who were screened regularly. Medically underserved 25-39-year-old women were also more likely to be identified with 'SIL/ASC' (odds ratio=1.64; 95% confidence interval=1.50, 1.79) than women 50 and over. Younger were more likely to have low-grade 'HPV/Condylomata, Atypia/CINI/LSIL' (odds ratio=2.48; 95% confidence interval=1.66, 3.72) and high-grade 'CIN II/III/HSIL/CI/Other Cancers' (odds ratio=1.53; 95% confidence interval=1.08, 2.16) than women age 40 and above, similar to rarely/never Pap-tested women. CONCLUSIONS:Women were more likely to be identified with high-grade precancerous cervical lesions and cancer process when they did not have regular screening, Ethnic differences in screening outcomes seem to be minimized by participation in a program that provides consistent screening resources to the medically underserved women who enroll. These findings support prevention strategies that expand screening to all medically underserved younger women or that provide HPV vaccination at an early age.