HART: Negative HPV screen has improved protection compared with negative cytology

HPV tests were more accurate than cytology screening at identifying early signs of cervical cancer and detecting more serious abnormalities in women aged 30 years or older.

The risk for developing cervical intraepithelial neoplasia grade 2 or higher (CIN2+) after a baseline negative HPV test was 0.23% at five years compared with 0.48% of women who had a negative cytology results at baseline.

Cervical cancer screening intervals could be extended to five years for these women if the primary screening method was HPV testing, according to the researchers.

Findings from previous studies showed HPV testing had improved sensitivity for CIN2+ but lower specificity than cytology.

Researchers from Queen Mary University of London compared long-term protection after HPV vs. cytology screening in 8,735 women from the HART study with at least one follow-up smear result with a median follow-up of six years. During follow-up, researchers observed an additional 42 cases of CIN2+.

The risk for developing CIN2+ was higher for women who were HPV positive at baseline vs. those who were HPV negative (HR=17.16; 95% CI, 9.3-31.6). The incidence of CIN2+ increased with increasing relative light unit.

When compared with a relative light unit ratio less than 1, the HR for CIN2+ was 5.4 (95% CI, 1.6-18.2) for a ratio of 1 to 10 and the HR was 25.5 (95% CI, 13.6-47.9) for a ratio of 10 or more.

When compared with negative cytology, borderline or worse cytology was predictive of developing CIN2+ (HR=8.74; 95% CI, 4.5-17.1).

Three women had CIN2 and one woman had CIN3, with HPV negative but cytology positive test results.

Mesher D. Br J Cancer. 2010;doi:10.1038/sj.bjc.6605619.