HPV testing in combination with liquid-based cytology in primary cervical screening

Prof Henry C Kitchener MD a Corresponding AuthorEmail Address, Maribel Almonte PhD c, Claire Thomson BSc a, Paula Wheeler MRes a, Alexandra Sargent PhD a, Boyka Stoykova MD d, Clare Gilham MSc e f, Helene Baysson PhD e, Christopher Roberts PhD b, Robin Dowie PhD d, Mina Desai MBchB g, Jean Mather MIBMS g, Andrew Bailey FIBMS h, Andrew Turner MB ChB h, Sue Moss PhD f, Prof Julian Peto DSc e f


Background
Testing for human papillomavirus (HPV) DNA is reportedly more sensitive than cytology for the detection of high-grade cervical intraepithelial neoplasia (CIN). The effectiveness of HPV testing in primary cervical screening was assessed in the ARTISTIC trial, which was done over two screening rounds approximately 3 years apart (2001—03 and 2004—07) by comparing liquid-based cytology (LBC) combined with HPV testing against LBC alone.

Methods
Women aged 20—64 years who were undergoing routine screening as part of the English National Health Service Cervical Screening Programme in Greater Manchester were randomly assigned (between July, 2001, and September, 2003) in a ratio of 3:1 to either combined LBC and HPV testing in which the results were revealed and acted on, or to combined LBC and HPV testing where the HPV result was concealed from the patient and investigator. The primary outcome was the detection rate of cervical intraepithelial neoplasia grade 3 or worse (CIN3+) in the second screening round, analysed by intention to treat. This trial is registered with the International Standard Randomised Controlled Trial Number ISRCTN25417821.

Findings
There were 24 510 eligible women at entry (18 386 in the revealed group, 6124 in the concealed group). In the first round of screening 233 women (1·27%) in the revealed group had CIN3+, compared with 80 (1·31%) women in the concealed group (odds ratio [OR] 0·97, 95% CI 0·75—1·25; p>0·2). There was an unexpectedly large drop in the proportion of women with CIN3+ between the first and second rounds of screening in both groups, at 0·25% (29 of 11 676) in the revealed group and 0·47% (18 of 3866 women) in the concealed group (OR 0·53, 95% CI 0·30—0·96; p=0·042). For both rounds combined, the proportion of women with CIN3+ were 1·51% (revealed) and 1·77% (concealed) (OR 0·85, 95% CI 0·67—1·08; p>0·2).

Interpretation
LBC combined with HPV testing resulted in a significantly lower detection rate of CIN3+ in the second round of screening compared with LBC screening alone, but the effect was small. Over the two screening rounds combined, co-testing did not detect a higher rate of CIN3+ or CIN2+ than LBC alone. Potential changes in screening methodology should be assessed over at least two screening rounds.

Funding
National Institute of Health Research Health Technology Assessment Programme.