Performance of Pap smear and human papilloma virus testing in the follow-up of women with cervical intraepithelial neoplasia grade 1 managed conservatively.

BACKGROUND

Conservative management (follow-up) of cervical intraepithelial neoplasia grade 1 (CIN1) is acceptable, but evidence on performance of follow-up tools, such as Pap smear and human papilloma virus (HPV) test, is still needed.

METHODS

A cohort of 78 women with histologically confirmed CIN1, referred because of atypical squamous cell or low-grade squamous intraepithelial lesion in their Pap smear, was enrolled between August 2000 and September 2002 and was prospectively followed-up at 6 and 12 months, until September 2003. Follow-up examinations included Pap test and Hybrid Capture II (HCII) with high-risk HPV, colposcopy, and cervical biopsies in patients with persistent abnormalities. Odds ratios and performance indicators (with 95% confidence interval) were calculated for HPV and Pap test results in detecting biopsy-confirmed CIN during the follow-up.

RESULTS

Thirty-seven (47%) of the women were HPV-positive at baseline. At first follow-up visit, 30 women had persistent CIN1 and one woman progressed to CIN2; 15 patients had CIN1 and one patient CIN2 at the second follow-up visit. Women with persistent CIN1 (or progression) during follow-up had a significantly higher HPV detection rate and abnormal Pap tests, compared to women with regressive disease. Cytology had a far better sensitivity in detecting CIN than HCII at the first follow-up visit (81 versus 52%, respectively), whereas both examinations had equivalent sensitivities at the second follow-up visit (69 and 56%, respectively). Cytology had a superior negative predictive value at the first follow-up visit and better positive predictive value, in addition, at the second visit.

CONCLUSIONS

Because cytological abnormalities correlated generally better with the persistence of biopsy-confirmed CIN1 in this follow-up protocol, HCII test is the second-hand option to Pap test, but the use of both Pap and HCII together seems an unnecessary waste of resources.