20/05/2008

Human Papillomavirus DNA versus Papanicolaou Screening Tests for
Cervical Cancer

Abstract

Background: To determine whether testing for DNA of oncogenic human
papillomaviruses (HPV) is superior to the Papanicolaou (Pap) test for cervicalcancer screening, we conducted a randomized trial comparing the two methods.

Methods We compared HPV testing, using an assay approved by the Food and
Drug Administration, with conventional Pap testing as a screening method to
identify high-grade cervical intraepithelial neoplasia in women ages 30 to 69
years in Montreal and St. John's, Canada. Women with abnormal Pap test
results or a positive HPV test (at least 1 pg of high-risk HPV DNA per milliliter)
underwent colposcopy and biopsy, as did a random sample of women with
negative tests. Sensitivity and specificity estimates were corrected for
verification bias.

Results A total of 10,154 women were randomly assigned to testing. Both tests
were performed on all women in a randomly assigned sequence at the same
session. The sensitivity of HPV testing for cervical intraepithelial neoplasia of
grade 2 or 3 was 94.6% (95% confidence interval [CI], 84.2 to 100), whereas the
sensitivity of Pap testing was 55.4% (95% CI, 33.6 to 77.2; P=0.01). The
specificity was 94.1% (95% CI, 93.4 to 94.8) for HPV testing and 96.8% (95%
CI, 96.3 to 97.3; P<0.001) for Pap testing. Performance was unaffected by the
sequence of the tests. The sensitivity of both tests used together was 100%,
and the specificity was 92.5%. Triage procedures for Pap or HPV testing
resulted in fewer referrals for colposcopy than did either test alone but were less
sensitive. No adverse events were reported.

Conclusions As compared with Pap testing, HPV testing has greater sensitivity
for the detection of cervical intraepithelial neoplasia. (Current Controlled Trials
number, ISRCTN57612064.)

Fonte: NEJM