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Objective To compare the accuracy of liquid based cytology using the computerised ThinPrep Imager with that of manually read conventional cytology.Design Prospective study.Setting Pathology laboratory in Sydney, Australia.Participants 55 164 split sample pairs (liquid based sample collected after conventional sample from one collection) from consecutive samples of women choosing both types of cytology and whose specimens were examined between August 2004 and June 2005.Main outcome measures Primary outcome was accuracy of slides for detecting squamous lesions. Secondary outcomes were rate of unsatisfactory slides, distribution of squamous cytological classifications, and accuracy of detecting glandular lesions.Results Fewer unsatisfactory slides were found for imager read cytology than for conventional cytology (1.8% v 3.1%; P<0.001). More slides were classified as abnormal by imager read cytology (7.4% v 6.0% overall and 2.8% v 2.2% for cervical intraepithelial neoplasia of grade 1 or higher). Among 550 patients in whom imager read cytology was cervical intraepithelial neoplasia grade 1 or higher and conventional cytology was less severe than grade 1, 133 of 380 biopsy samples taken were high grade histology. Among 294 patients in whom imager read cytology was less severe than cervical intraepithelial neoplasia grade 1 and conventional cytology was grade 1 or higher, 62 of 210 biopsy samples taken were high grade histology. Imager read cytology therefore detected 71 more cases of high grade histology than did conventional cytology, resulting from 170 more biopsies. Similar results were found when one pathologist reread the slides, masked to cytology results.Conclusion The ThinPrep Imager detects 1.29 more cases of histological high grade squamous disease per 1000 women screened than conventional cytology, with cervical intraepithelial neoplasia grade 1 as the threshold for referral to colposcopy. More imager read slides than conventional slides were satisfactory for examination and more contained low grade cytological abnormalities. INTRODUCTIONAlthough manual checking of conventional cervical smears has been used for decades to screen for cervical cancer and precancerous cells, liquid based cytology is replacing conventional cytology in many countries. The potential advantages of liquid based cytology are adjunctive testing, including testing for human papillomavirus; faster reading times; and cost saving of automation. Evidence is insufficient, however, to confirm that liquid based cytology is more accurate than conventional cytology, 1 which continues to be widely used.Conventional cytology involves the transference of cervical material from a collection instrument on to a glass slide whereas liquid based cytology (for example, the ThinPrep Liquid-based Cytology Preparation system, Cytyc, Marlborough, MA) involves rinsing the collection instrument in liquid to produce a suspension, which is processed in a laboratory to produce a monolayer of cells. The ThinPrep Imager (Cytyc) system, a computerised sy...

BackgroundThe incidence of human papillomavirus (HPV)-associated anal cancer is increasing in men who have sex with men (MSM). Screening for the presumed cancer precursor, high-grade anal squamous intraepithelial lesions (HSIL) in a manner analogous to cervical cancer screening has been proposed. Uncertainty remains regarding anal HPV natural history and the role of anal cytology and high-resolution anoscopy (HRA) as screening tests. Well-designed cohort studies are required to address these issues.Methods/designThe SPANC study is a prospective study of the epidemiology of low-risk and high-risk anal HPV infection and related cytological and histological abnormalities in HIV-negative and HIV-positive homosexual men aged 35 years and over. The study aims to recruit 600 men from community-based settings in Sydney, Australia. There are six study visits over three years. At the first five visits men undergo a digital ano-rectal examination (DARE), an anal “Papanicolaou” (Pap) test for HPV detection, genotyping and anal cytology, followed by HRA and directed biopsy of any visible abnormalities. The men also complete a behavioural questionnaire before each visit. Questions include a detailed history of sexual behaviour, of anal symptoms, possible anal cancer risk factors and validated quality of life and psychosocial questions. Questionnaires are also completed 2 weeks and 3 months following the provision of test results and include questions on participant experience during the procedure and post-procedure symptoms, including pain and bleeding in addition to quality of life/ psychosocial outcomes.DiscussionRecruitment for the study began in September 2010 and will conclude in mid-2015, with follow up continuing to 2018. Thus far, over 350 men have been recruited from a variety of community-based settings and are broadly representative of the target screening population. The SPANC study is one of only a small number of cohort studies globally to perform HPV, cytology and HRA screening on all participants over multiple time points. The study results will contribute to understanding of the natural history of anal HPV and inform the possible development of guidelines for implementing anal cancer screening programs in this population.

BackgroundUsing primary human papillomavirus (HPV) testing for cervical screening increases detection of high-grade cervical intraepithelial neoplastic lesions and invasive cancer (cervical intraepithelial neoplasia grade 2+ [CIN2+]) compared to cytology, but no evaluation has been conducted in a population previously offered HPV vaccination. We aimed to assess colposcopy referral and CIN2+ detection rates for HPV-screened versus cytology-screened women in Australia’s HPV-vaccinated population (by 2014, resident women ≤33 years had been age-eligible for HPV vaccination, with 3-dose uptake across age cohorts being about 50%–77%).Methods and findingsCompass is an open-label randomised trial of 5-yearly HPV screening versus 2.5-yearly liquid-based cytology (LBC) screening. In the first phase, consenting women aged 25–64 years presenting for routine screening at 47 primary practices in Victoria, Australia, provided a cervical sample and were randomised at a central laboratory at a 1:2:2 allocation to (i) image-read LBC screening with HPV triage of low-grade cytology (‘LBC screening’), (ii) HPV screening with those HPV16/18 positive referred to colposcopy and with LBC triage for other oncogenic (OHR) types (‘HPV+LBC triage’), or (iii) HPV screening with those HPV16/18 positive referred to colposcopy and with dual-stained cytology triage for OHR types (‘HPV+DS triage’). A total of 5,006 eligible women were recruited from 29 October 2013 to 7 November 2014 (recruitment rate 58%); of these, 22% were in the group age-eligible for vaccination. Data on 4,995 participants were analysed after 11 withdrawals; 998 were assigned to, and 995 analysed (99.7%) in, the LBC-screened group; 1,996 assigned to and 1,992 analysed (99.8%) in the HPV+LBC triage group; and 2,012 assigned to and 2,008 analysed (99.8%) in the HPV+DS triage group. No serious trial-related adverse events were reported. The main outcomes were colposcopy referral and detected CIN2+ rates at baseline screening, assessed on an intention-to-treat basis after follow-up of the subgroup of triage-negative women in each arm referred to 12 months of surveillance, and after a further 6 months of follow-up for histological outcomes (dataset closed 31 August 2016). Analysis was adjusted for whether women had been age-eligible for HPV vaccination or not. For the LBC-screened group, the overall referral and detected CIN2+ rates were 27/995 (2.7% [95% CI 1.8%–3.9%]) and 1/995 (0.1% [95% CI 0.0%–0.6%]), respectively; for HPV+LBC triage, these were 75/1,992 (3.8% [95% CI 3.0%–4.7%]) and 20/1,992 (1.0% [95% CI 0.6%–1.5%]); and for HPV+DS triage, these were 79/2,008 (3.9% [95% CI 3.1%–4.9%]) and 24/2,008 (1.2% [95% CI 0.8%–1.6%]) (p = 0.09 for difference in referral rate in LBC versus all HPV-screened women; p = 0.003 for difference in CIN2+ detection rate in LBC versus all HPV-screened women, with p = 0.62 between HPV screening groups). Limitations include that the study population involved a relatively low risk group in a previously well-screened and treated population, that ind...