Human papillomavirus testing versus cytology in primary cervical cancer screening: End‐of‐study and extended follow‐up results from the Canadian cervical cancer screening trial

The Canadian Cervical Cancer Screening Trial was a randomized controlled trial comparing the performance of human papillomavirus (HPV) testing and Papanicolaou cytology to detect cervical intraepithelial neoplasia of grades 2 or worse (CIN2+) among women aged 30–69 years attending routine cervical cancer screening in Montreal and St. John's, Canada (n = 10,154). We examined screening and prognostic values of enrollment cytologic and HPV testing results. Extended follow‐up data were available for St. John's participants (n = 5,754; 501,682.6 person‐months). HPV testing detected more CIN2+ than cytology during protocol‐defined (82.9 vs. 44.4%) and extended (54.2 vs. 19.3%) follow‐up periods, respectively. Three‐year risks ranged from 0.87% (95% CI: 0.37–2.05) for HPV‐/Pap‐ women to 35.77% (95% CI: 25.88–48.04) for HPV+/Pap+ women. Genotype‐specific risks ranged from 0.90% (95% CI: 0.40–2.01) to 43.84% (95% CI: 32.42–57.24) among HPV? and HPV16+ women, respectively, exceeding those associated with Pap+ or HPV+ results taken individually or jointly. Ten‐year risks ranged from 1.15% (95% CI: 0.60–2.19) for HPV?/Pap? women to 26.05% (95% CI: 15.34–42.13) for HPV+/Pap+ women and genotype‐specific risks ranged from 1.13% (95% CI: 0.59–2.14) to 32.78% (95% CI: 21.15–48.51) among women testing HPV? and HPV16+, respectively. Abnormal cytology stratified risks most meaningfully for HPV+ women. Primary HPV testing every 3 years provided a similar or greater level of reassurance against disease risks as currently recommended screening strategies. HPV‐based cervical screening may allow for greater disease detection than cytology‐based screening and permit safe extensions of screening intervals; genotype‐specific testing could provide further improvement in the positive predictive value of such screening.     

Disease detection at the 48-month exit round of the HPV FOCAL cervical cancer screening trial in women per-protocol eligible for routine screening

HPV FOCAL is a randomized control trial of cervical cancer screening. The intervention arm received baseline screening for high-risk human papillomavirus (HPV) and the control arm received liquid-based cytology (LBC) at baseline and 24 months. Both arms received 48-month exit HPV and LBC cotesting. Exit results are presented for per-protocol eligible (PPE) screened women. Participants were PPE at exit if they had completed all screening and recommended follow-up and had not been diagnosed with cervical intraepithelial neoplasia Grade 2 or worse (CIN2+) earlier in the trial. Subgroups were identified based upon results at earlier trial screening. There were 9,457 and 9,552 and women aged 25–65 randomized to control and intervention and 7,448 (77.8%) and 8,281 (86.7%), respectively, were PPE and screened. Exit cotest results were similar (p = 0.11) by arm for PPE and the relative rate (RR) of CIN2+ for intervention vs. control was RR = 0.83 (95% CI: 0.56–1.23). The RR for CIN2+ comparing intervention women baseline HPV negative to control women with negative cytology at baseline and at 24 months, was 0.68 (95% CI: 0.43–1.06). PPE women who had a negative or CIN1 colposcopy in earlier rounds had elevated rates (per 1,000) of CIN2+ at exit, control 31 (95% CI: 14–65) and intervention 43 (95% CI: 25–73). Among PPE women HPV negative at exit LBC cotesting identified little CIN2+, Rate = 0.3 (95% CI: 0.1–0.7). This per-protocol analysis found that screening with HPV using a 4-year interval is as safe as LBC with a 2-year screening interval. LBC screening in HPV negative women at exit identified few additional lesions.     

Prevalence of human papillomavirus and cervical intraepithelial neoplasia in China: A pooled analysis of 17 population-based studies

High-risk (HR) human papillomavirus (HPV) prevalence has been shown to correlate well with cervical cancer incidence rates. Our study aimed to estimate the prevalence of HR-HPV and cervical intraepithelial neoplasia (CIN) in China and indirectly informs on the cervical cancer burden in the country. A total of 30,207 women from 17 population-based studies throughout China were included. All women received HPV DNA testing (HC2, Qiagen, Gaithersburg, MD), visual inspection with acetic acid and liquid-based cytology. Women positive for any test received colposcopy-directed or four-quadrant biopsies. A total of 29,579 women had HR-HPV testing results, of whom 28,761 had biopsy confirmed (9,019, 31.4%) or assumed (19,742, 68.6%) final diagnosis. Overall crude HR-HPV prevalence was 17.7%. HR-HPV prevalence was similar in rural and urban areas but showed dips in different age groups: at age 25–29 (11.3%) in rural and at age 35–39 (11.3%) in urban women. In rural and urban women, age-standardized CIN2 prevalence was 1.5% [95% confidence interval (CI): 1.4–1.6%] and 0.7% (95% CI: 0.7–0.8%) and CIN3+ prevalence was 1.2% (95% CI: 1.2–1.3%) and 0.6% (95% CI: 0.5–0.7%), respectively. Prevalence of CIN3+ as a percentage of either all women or HR-HPV-positive women steadily increased with age, peaking in 45- to 49-year-old women. High prevalence of HR-HPV and CIN3+ was detected in both rural and urban China. The steady rise of CIN3+ up to the age group of 45–49 is attributable to lack of lesion removal through screening. Our findings document the inadequacy of current screening in China while indirectly raising the possibility that the cervical cancer burden in China is underreported.     

Effects of exposure to polycyclic aromatic hydrocarbons combined with high-risk human papillomavirus infection on cervical intraepithelial neoplasia: A population study in Shanxi Province,China

High-risk human papillomavirus (HR-HPV) infection is a major etiological agent in the progression of cervical intraepithelial neoplasia (CIN) and cervical cancer. Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic pollutants that exist widely in the environment. We hypothesized that PAHs exposure was related to the progression of cervical cancer, and could increase the effect of HR-HPV on CIN. We investigated the effects of PAHs exposure combined with HR-HPV infection on CIN in community population in Shanxi Province, China. A total of 2,285 women were enrolled into the study. HR-HPV genotypes were detected by flow-through hybridization technology. 1-hydroxypyrene (1-OHP) was detected by high-performance liquid chromatography. The top three HR-HPV genotypes were 16, 58 and 52 in turn. With unconditional logistic regression analysis, we found that HR-HPV infection (adjusted odds ratio [aOR] = 4.08, 95% confidence interval [CI]: 3.00–5.54), HPV16 infection (aOR = 4.71, 95% CI: 3.39–6.53), HPV58 infection (aOR = 2.29, 95% CI: 1.41–3.73) and PAHs high exposure (aOR = 2.57, 95% CI: 1.82–3.62) increased the risk of CIN2/3, showing an increasing trend (p < 0.001) with the severity of cervical lesions. Compared to Q1 (<0.06 μmol/molCr) levels of 1-OHP, women with Q4 (>0.11 μmol/molCr) had a higher risk for CIN2/3 (aOR = 7.68, 95% CI: 4.83–12.22). Additionally, we observed that there was a synergic effect between high exposure to PAHs and HR-HPV infection in CIN2/3. Furthermore, the results from the generalized multifactor dimensionality reduction model showed that there were joint interactions of PAHs, HPV16, HPV58 and HPV52 on the risk of CIN2/3. Our study revealed that high exposure to PAHs could increase the risk for CIN, and it posed stronger risk when combined with HR-HPV infection.     

Risk of cervical intraepithelial neoplasia grade 2 or worse after conization in relation to HPV vaccination status

Human papillomavirus (HPV) is essential for developing cervical cancer and precancerous lesions. Currently, three vaccines are available, which are effective as prophylaxis against HPV infection, however, limited knowledge exists about the possible effect of vaccinating women treated with conization to prevent recurrence. The aim of our study was to examine the risk of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) after conization according to HPV vaccination status. Using Danish nationwide registries, we identified women diagnosed with CIN3 on the cone (2006–2012) and their HPV vaccination status. Vaccinees were defined as women vaccinated between 3 months before until 1 year after conization. The women were followed from 1 year after conization until diagnosis of CIN2+, conization, death, emigration or end of follow-up. Cox proportional hazard regression was used to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) of CIN2+ comparing vaccinees with nonvaccinees. The HR was adjusted for age, histology on cone, education, year of conization, repeat conizations and CIN2+ lesions between conization and start of follow-up. Altogether 17,128 women were included (2,074 vaccinees). There was a statistically nonsignificant lower risk of CIN2+ among vaccinees (HR_adjusted = 0.86, 95% CI: 0.67–1.09). Women vaccinated 0–3 months before tended to have a slightly lower HR of CIN2+ (HR_adjusted = 0.77, 95% CI: 0.45–1.32) than women vaccinated 0–12 months after conization (HR_adjusted = 0.88, 95% CI: 0.67–1.14), although not statistically significantly different. Our results add to the current knowledge about the potential clinical effect of vaccination as an adjunct to conization of high-grade cervical neoplasia to decrease risk of recurrence.     

A daunting challenge: Human Papillomavirus assays and cytology in primary cervical screening of women below age 30 years

We compared cytology with Hybrid Capture 2 (HC2), cobas, CLART and APTIMA Human Papillomavirus (HPV) assays in primary cervical screening at age 23–29 years based on data from the Danish Horizon study. SurePath samples were collected from 1278 women undergoing routine cytology-based screening. Abnormal cytology was managed according to the routine recommendations, and women with cytology-normal/HPV-positive samples were invited for repeated cytology and HPV testing in 1.5 years. Loss to follow-up was similar between HPV assays. ⩾CIN3 was detected in 44 women. The sensitivity of HC2 for ⩾CIN3 was 95% (95% confidence interval (CI): 85–99), of cobas 98% (95% CI: 88–100), of CLART 100% (95% CI: 92–100), of APTIMA 82% (95% CI: 67–92), and of cytology 59% (95% CI: 43–74). Specificity for ⩾CIN3 varied between 61% (95% CI: 59–64) for cobas and 75% (95% CI: 73–78) for APTIMA, and was 94% (95% CI: 93–96) for cytology. Similar results were observed for ⩾CIN2 (N = 68). HPV screening with cytological triage doubled the number of colposcopies compared to cytology screening, and increased the frequency of repeated testing by four (APTIMA) to seven (cobas) times. The positive predictive value of a referral for colposcopy was relatively high for all screening tests (⩾30% for ⩾CIN3, and ⩾50% for ⩾CIN2). CIN1 was detected by cytology in ∼1% of women, and in ∼2% by any of the four HPV assays. Although highly sensitive, HPV-based screening of young Danish women should be approached cautiously, as it resulted in large reductions in specificity, and increased the demand for additional testing.     

High‐risk human papillomavirus DNA load in a population‐based cervical screening cohort in relation to the detection of high‐grade cervical intraepithelial neoplasia and cervical cancer

In a population‐based cervical screening cohort, we determined the value of type‐specific viral load assessment for the detection of high‐grade cervical intraepithelial neoplasia and cervical cancer (≥CIN2). Viral load was determined by type‐specific real‐time PCR in women with single HPV16,‐18,‐31 and ‐33 infections, as determined by GP5+/6+‐PCR. Study endpoints were the detection of cumulative ≥CIN2 or ≥CIN3 within 18 months of follow‐up. High viral loads of HPV16,‐31, and ‐33 were predictive for ≥CIN2 (relative risk of 1.6 (95% CI: 1.3–1.9), 1.7 (95% CI: 1.1–2.7) and 1.9 (95% CI: 1.1–3.1) per 10‐fold change in viral load, respectively). For HPV18, the relative risk was of similar magnitude (1.5, 95% CI: 0.7–3.1), though not significant (p = 0.3). Subsequently, we determined the sensitivities of viral load for ≥CIN2 and ≥CIN3 in HPV DNA‐positive women using viral load thresholds previously defined in a cross‐sectional study. These thresholds were based on the 25th, 33rd and 50th percentiles of type‐specific HPV16,‐18,‐31 or ‐33 viral load values found in women with normal cytology. For all types, combined sensitivities for ≥CIN2 were 93.5%, 88.8% and 77.7% for the 25th, 33rd and 50th percentile thresholds, respectively. Response‐operator‐characteristics (ROC) curve analysis showed that viral load testing on HPV DNA‐positive women in addition to or instead of cytology may result in an increased sensitivity for ≥CIN2, but at the cost of a marked decrease in specificity in relation to cytology. Similar results were obtained when using ≥CIN3 as endpoint. In conclusion, in a cervical screening setting viral load assessment of HPV16, 18, 31 and 33 has no additive value to stratify high‐risk HPV GP5+/6+‐PCR‐positive women for risk of ≥CIN2 or ≥CIN3. © 2008 Wiley‐Liss, Inc.     

Long‐term risk of cervical intraepithelial neoplasia grade 3 or worse according to high‐risk human papillomavirus genotype and semi‐quantitative viral load among 33,288 women with normal cervical cytology

In this prospective cohort study, we estimated the long‐term risk of cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) by high‐risk human papillomavirus (hrHPV) genotype and semi‐quantitative viral load at baseline among 33,288 women aged 14–90 years with normal baseline cytology. During 2002–2005, residual liquid‐based cervical cytology samples were collected from women screened for cervical cancer in Copenhagen, Denmark. Samples were HPV‐tested with Hybrid Capture 2 (HC2) and genotyped with INNO‐LiPA. Semi‐quantitative viral load was measured by HC2 relative light units in women with single hrHPV infections. The cohort was followed in a nationwide pathology register for up to 11.5 years. In women aged ≥30 years at baseline, the 8‐year absolute risk for CIN3+ following baseline detection of HPV16 was 21.8% (95% confidence interval [CI]: 18.0–25.6%). The corresponding risks for HPV18, HPV31, HPV33, and other hrHPV types, respectively, were 12.8% (95% CI: 7.6–18.0%), 11.3% (95% CI: 7.7–14.9%), 12.9% (95% CI: 7.0–18.8%) and 3.9% (95% CI: 2.7–5.2%). Similar absolute risk estimates were observed in women aged <30 years. Higher HPV16‐viral load was associated with increased risk of CIN3+ (hazard ratio = 1.34, 95% CI: 1.10–1.64, per 10‐fold increase in viral load). A similar trend, although statistically nonsignificant, was found for viral load of HPV18. The 8‐year absolute risk of CIN3+ in women with HPV16‐viral load ≥100.0 pg/ml was 30.2% (95% CI: 21.9–38.6%). Our results support that hrHPV genotyping during cervical cancer screening may help identify women at highest risk of CIN3+.     

Reliable identification of women with CIN3+ using hrHPV genotyping and methylation markers in a cytology-screened referral population

Cervical screening aims to identify women with high-grade squamous intraepithelial lesion/cervical intraepithelial neoplasia 2-3 (HSIL/CIN2-3) or invasive cervical cancer (ICC). Identification of women with severe premalignant lesions or ICC (CIN3+) could ensure their rapid treatment and prevent overtreatment. We investigated high-risk human papillomavirus (hrHPV) detection with genotyping and methylation of FAM19A4/miR124-2 for detection of CIN3+ in 538 women attending colposcopy for abnormal cytology. All women had an additional cytology with hrHPV testing (GP5+/6+-PCR-EIA+), genotyping (HPV16/18, HPV16/18/31/45), and methylation analysis (FAM19A4/miR124-2) and at least one biopsy. CIN3+ detection was studied overall and in women <30 (n = 171) and ≥30 years (n = 367). Positivity for both rather than just one methylation markers increased in CIN3, and all ICC was positive for both. Overall sensitivity and specificity for CIN3+ were, respectively, 90.3% (95%CI 81.3–95.2) and 31.8% (95%CI 27.7–36.1) for hrHPV, 77.8% (95%CI 66.9–85.8) and 69.3% (95%CI 65.0–73.3) for methylation biomarkers and 93.1% (95%CI 84.8–97.0) and 49.4% (95%CI 44.8–53.9) for combined HPV16/18 and/or methylation positivity. For CIN3, hrHPV was found in 90.9% (95%CI 81.6–95.8), methylation positivity in 75.8% (95%CI 64.2–84.5) and HPV16/18 and/or methylation positivity in 92.4% (95%CI 83.5–96.7). In women aged ≥30, the sensitivity of combined HPV16/18 and methylation was increased (98.2%, 95%CI 90.6–99.7) with a specificity of 46.3% (95%CI 40.8–51.9). Combination of HPV16/18 and methylation analysis was very sensitive and offered improved specificity for CIN3+, opening the possibility of rapid treatment for these women and follow-up for women with potentially regressive, less advanced, HSIL/CIN2 lesions.     

Cumulative 5-year diagnoses of CIN2, CIN3 or cervical cancer after concurrent high-risk HPV and cytology testing in a primary screening setting

The aim of our study was to assess the cumulative 5-year diagnoses of CIN2, CIN3 or invasive cervical cancer (CIN2+) after concurrent screening by high-risk HPV test and Pap smear in a primary screening setting. Four thousand thirty-four women from Eastern Thuringia/Germany were recruited from 1996 to 1998 for baseline screening that included routine cytology, high-risk HPV testing by consensus primer PCR GP5+/6+ and routine colposcopy. After a median of 59 months 3,153 women participated in final screening using identical methods. Women with abnormal cytology or colposcopy or a positive high-risk HPV test at any time during the study period were recalled for expert colposcopy and histologic verification. CIN2+ was detected in 160 women resulting in a cumulative 5-year proportion of 4.4% (95% CI: 3.7-5.0%). Of 3,702 women who were high-risk HPV negative at baseline, 34 (1.1-95% CI: 0.7-1.4%) had either prevalent CIN2+ or developed CIN2+ within the observation period. HPV/cytology double negatives at baseline were at lowest risk for CIN2+ (1.0-95% CI: 0.7-1.4%) compared to screening positives (16.8-100% depending on combined test results). The 5-year negative predictive value in HPV-/Cyto- women was 99.0% (95% CI: 98.6-99.3%). This suggests that a prolongation of the screening intervals in this group is feasible. However, it should be noted that 1 woman developed a microinvasive carcinoma within the observation period. Moreover, 2 women with prevalent cancer were missed by both tests. The prognostic relevance of concurrent high-risk HPV/cytology screening needs to be verified further by randomized trials.     

Posttreatment human papillomavirus testing for residual or recurrent high-grade cervical intraepithelial neoplasia: a pooled analysis

Objective

We conducted a pooled analysis of published studies to compare the performance of human papillomavirus (HPV) testing and cytology in detecting residual or recurrent diseases after treatment for cervical intraepithelial neoplasia grade 2 or 3 (CIN 2/3).

Methods

Source articles presenting data on posttreatment HPV testing were identified from the National Library of Medicine (PubMed) database. We included 5,319 cases from 33 articles published between 1996 and 2013.

Results

The pooled sensitivity of high-risk HPV testing (0.92; 95% confidence interval [CI], 0.90 to 0.94) for detecting posttreatment CIN 2 or worse (CIN 2+) was much higher than that of cytology (0.76; 95% CI, 0.71 to 0.80). Co-testing of HPV testing and cytology maximized the sensitivity (0.93; 95% CI, 0.87 to 0.96), while HPV genotyping (detection of the same genotype between pre- and posttreatments) did not improve the sensitivity (0.89; 95% CI, 0.82 to 0.94) compared with high-risk HPV testing alone. The specificity of high-risk HPV testing (0.83; 95% CI, 0.82 to 0.84) was similar to that of cytology (0.85; 95% CI, 0.84 to 0.87) and HPV genotyping (0.83; 95% CI, 0.81 to 0.85), while co-testing had reduced specificity (0.76; 95% CI, 0.75 to 0.78). For women with positive surgical margins, high-risk HPV testing provided remarkable risk discrimination between test-positives and test-negatives (absolute risk of residual CIN 2+ 74.4% [95% CI, 64.0 to 82.6] vs. 0.8% [95% CI, 0.15 to 4.6]; p<0.001).

Conclusion

Our findings recommend the addition of high-risk HPV testing, either alone or in conjunction with cytology, to posttreatment surveillance strategies. HPV testing can identify populations at greatest risk of posttreatment CIN 2+ lesions, especially among women with positive section margins.     

Prevalence of types 16 and 33 is increased in high-risk human papillomavirus positive women with cervical intraepithelial neoplasia grade 2 or worse

High-risk human papillomavirus (hrHPV) types are causally related to cervical cancer and its high-grade precursor lesions. The risk posed by the different hrHPV types for the development of cervical intraepithelial neoplasia grade 2 or worse (> or =CIN2) needs to be established. Here, we present the hrHPV type-distribution in relation to cytology and histology for women participating in a cervical screening program. From 44,102 women who participated in a population-based cervical screening program in the Netherlands, 2,154 hrHPV GP5+/6+ PCR positive women were recruited to determine the distribution of 14 hrHPV types by reverse line blotting of GP5+/6+ PCR products. For each HPV type, associations with cytology and histologically confirmed > or =CIN2 were measured by odds ratios. HPV types 16 and 33 were more prevalent in women, amongst those containing a single hrHPV type, with moderate dyskaryosis or worse (>BMD) than in women with normal cytology, but only in case of underlying > or =CIN2 (OR 4.10, 95%CI 2.98-5.64 and OR 2.68, 95%CI 1.39-5.15, respectively). Similar results were obtained for women with double infections (OR 3.29, 95% CI 1.61-6.75 and OR 4.37, 95% CI 1.17-16.34). Coexisting types did not influence the prevalence of > or =CIN2 in HPV 16 or 33 positive women. The increased prevalence of type 16 and 33 in hrHPV positive women with > or =CIN2, compared to women with normal cytology, suggests that infection with these types confers an increased risk for development of > or =CIN2. Distinguishing these types may therefore have implications for future cervical screening strategies.     

Absolute risks of cervical precancer among women who fulfill exiting guidelines based on HPV and cytology cotesting

US guidelines recommend that most women older than 65 years cease cervical screening after two consecutive negative cotests (concurrent HPV and cytology tests) in the previous 10 years, with one in the last 5 years. However, this recommendation was based on expert opinion and modeling rather than empirical data on cancer risk. We therefore estimated the 5-year risks of cervical precancer (cervical intraepithelial neoplasia grade 3 or adenocarcinoma in situ [CIN3]) after one, two and three negative cotests among 346,760 women aged 55–64 years undergoing routine cotesting at Kaiser Permanente Northern California (2003–2015). Women with a history of excisional treatment or CIN2+ were excluded. No woman with one or more negative cotests was diagnosed with cancer during follow-up. Five-year risks of CIN3 after one, two, and three consecutive negative cotests were 0.034% (95% CI: 0.023%–0.046%), 0.041% (95% CI: 0.007%–0.076%) and 0.016% (95% CI: 0.000%–0.052%), respectively (p_trend < 0.001). These risks did not appreciably differ by a positive cotest result prior to the one, two or three negative cotest(s). Since CIN3 risks after one or more negative cotests were significantly below a proposed 0.12% CIN3+ risk threshold for a 5-year screening interval, a longer screening interval in these women is justified. However, the choice of how many negative cotests provide sufficient safety against invasive cancer over a woman's remaining life represents a value judgment based on the harms versus benefits of continued screening. Ideally, this guideline should be informed by longer-term follow-up given that exiting is a long-term decision.     

Persistence and load of high-risk HPV are predictors for development of high-grade cervical lesions: a longitudinal French cohort study

Oncogenic HPV types are the major cause of worldwide cervical cancer, but only a small proportion of infected women will develop high-grade cervical intraepithelial neoplasia or cancer (CIN2/3+). We performed a prospective study including 781 women with normal, atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesion (LGSIL) cytology, and infected or not by high-risk (HR) HPV tested by Hybrid Capture II. Women were followed up every 6 months for a median period of 22 months. Among the HR-HPV-positive women at entry, more than half cleared their virus in 7.5 months; the clearance rate was greater for low viral loads than for high loads and also was higher in women with an initial ASCUS/LGSIL smear than in women with normal cytology. The incidence of cytologic abnormalities strongly depended on baseline viral load and HR-HPV persistence. Maintenance of cytologic abnormalities was associated with the outcome of HR-HPV status (negative or =100 pg/mL). Conversely, women who were consistently HR-HPV negative or transiently HR-HPV positive, whatever the cytology at baseline was, did not develop CIN2/3+ during follow-up. Age seemed to affect only the rate of incident HR-HPV infection. In conclusion, our data suggest that women repeatedly tested positive for HR-HPV are at risk of developing CIN2/3+, even when initial cytology is normal. A high viral load could be used as a short-term marker of progression toward precancerous lesions, although lower load does not inevitably exclude progressive disease.     

Triaging HPV‐positive women with normal cytology by p16/Ki‐67 dual‐stained cytology testing: Baseline and longitudinal data

Primary human papillomavirus (HPV)‐based screening results in a 2–5% lower specificity for cervical intraepithelial neoplasia Grade 2 or worse (CIN2+) compared to Pap cytology. To identify HPV‐positive women with CIN2+, we retrospectively evaluated the cross‐sectional and longitudinal performance of p16/Ki‐67 dual‐stained cytology in HPV‐positive women with normal cytology participating in population‐based cervical screening. Conventional Pap cytology specimens of 847 of these women derived from the VUSA‐Screen study were dual‐stained for p16/Ki‐67. Cross‐sectional clinical performance in detecting CIN3 or worse (CIN3+), and CIN2+ was compared to that of baseline HPV genotyping. Moreover, 5‐year cumulative incidence risks (CIR) for CIN3+ (CIN2+) were determined. The sensitivity of p16/Ki‐67 dual‐stained cytology for CIN3+ (CIN2+) was 73.3% (68.8%) with a specificity of 70.0% (72.8%). HPV16/18 genotyping showed a sensitivity for CIN3+ (CIN2+) of 46.7% (43.8%), with a specificity of 78.3% (79.4%). The 5‐year CIR for CIN3+ in HPV‐positive women with normal cytology was 6.9%. Testing these women with p16/Ki‐67 dual‐stained cytology resulted in a significantly lower CIN3+ 5‐year CIR of 3.3% (p = 0.017) in case of a negative test result. A negative HPV16/18 genotyping test result also led to a lower 5‐year CIN3+ CIR of 3.6%. p16/Ki‐67 dual‐stained cytology detects more than 70% of underlying CIN3+ lesions in HPV‐positive women with normal cytology at baseline and is therefore suitable for triaging these women to colposcopy. Furthermore, the CIN3+ 5‐year CIR of 3.3% after a negative dual‐stain result is significantly lower compared to the 5‐year CIR of 6.9% in women without p16/Ki‐67 dual‐stained cytology triage.     

Predicting CIN2+ when detecting HPV mRNA and DNA by PreTect HPV-proofer and consensus PCR: A 2-year follow-up of women with ASCUS or LSIL Pap smear

It has been suggested that human papillomavirus (HPV) testing improves follow-up of atypical cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesion (LSIL) in cervical cancer screening programs. To evaluate the prognostic value of including HPV testing as an adjunct to cytology, we carried out a 2-year follow-up study of 77 women with ASCUS or LSIL Papanicolaou (Pap) smear in the Norwegian Cervical Cancer Screening Program (NCCSP) for detection of histological cervical intraepithelial neoplasia (CIN) 2+. The study includes a comparison between viral mRNA and DNA detection. PreTect HPV-Proofer was used for HPV E6/E7 mRNA detection from the 5 high-risk types 16, 18, 31, 33 and 45, and Gp5+/6+ consensus PCR was used for HPV DNA detection. Twice as many women were positive for HPV DNA (54.6%) than for HPV mRNA (23.4%). PreTect HPV-Proofer and consensus PCR had a sensitivity of 85.7% (95% confidence interval [CI] = 42.1-99.6) for detecting CIN2+ during follow-up. The specificity was significantly higher for PreTect HPV-Proofer, 84.9% (95% CI = 73.9-92.5), than for consensus PCR, 50.0% (95% CI = 37.4-62.6). PreTect HPV-Proofer positive women were 69.8 times (95% CI = 4.3-1137.3) more likely to be diagnosed with CIN2+ within 2 years than PreTect HPV-Proofer negative women. Consensus PCR-positive women were 5.7 times (95% CI = 0.6-52.0) more likely to be diagnosed with CIN2+ within 2 years than PCR-negative women. With equal sensitivity and higher specificity than consensus PCR, the PreTect HPV-Proofer might offer an improvement for the triage of women with ASCUS or LSIL Pap smear.     

HPV for cervical cancer screening (HPV FOCAL): Complete Round 1 results of a randomized trial comparing HPV‐based primary screening to liquid‐based cytology for cervical cancer

Complete Round 1 data (baseline and 12‐month follow‐up) for HPV FOCAL, a randomized trial establishing the efficacy of HPV DNA testing with cytology triage as a primary screen for cervical cancer are presented. Women were randomized to one of three arms: Control arm – Baseline liquid‐based cytology (LBC) with ASCUS results triaged with HPV testing; Intervention and Safety arms – Baseline HPV with LBC triage for HPV positives. Results are presented for 15,744 women allocated to the HPV (intervention and safety combined) and 9,408 to the control arms. For all age cohorts, the CIN3+ detection rate was higher in the HPV (7.5/1,000; 95%CI: 6.2, 8.9) compared to the control arm (4.6/1,000; 95%CI: 3.4, 6.2). The CIN2+ detection rates were also significantly higher in the HPV (16.5/1,000; 95%CI: 14.6, 18.6) vs. the control arm (10.1/1,000; 95%CI: 8.3, 12.4). In women ≥35 years, the overall detection rates for CIN2+ and CIN3+ were higher in the HPV vs. the control arm (CIN2+:10.0/1,000 vs. 5.2/1,000; CIN3+: 4.2/1,000 vs. 2.2/1,000 respectively, with a statistically significant difference for CIN2+). HPV testing detected significantly more CIN2+ in women 25–29 compared to LBC (63.7/1,000; 95%CI: 51.9, 78.0 vs. 32.4/1,000; 95%CI: 22.3, 46.8). HPV testing resulted in significantly higher colposcopy referral rates for all age cohorts (HPV: 58.9/1,000; 95%CI: 55.4, 62.7 vs. control: 30.9/1,000; 95%CI: 27.6, 34.6). At completion of Round 1 HPV‐based cervical cancer screening in a population‐based program resulted in greater CIN2+ detection of across all age cohorts compared to LBC screening.     

Incidence of cervical intraepithelial neoplasia in women infected with human immunodeficiency virus (HIV) with no evidence of disease at baseline: Results of a prospective cohort study with up to 6.4 years of follow-up from India

We report the incidence of cervical intraepithelial neoplasia (CIN) among HIV-infected women who did not have any colposcopic or histopathological evidence of CIN at baseline. Of the 1,023 women without any CIN at baseline, 855 (83.6%) have been followed up to a maximum of 6.4 years contributing 2,875 person years of observation (PYO). Among these 855 women, 54 cases of any CIN were observed resulting in incidence rate of any CIN of 1.9 per 100 PYO. The median time for follow-up for women with any CIN was 3.0 (IQR 1.6–3.7) years. The cumulative incidence rate per 100 PYO of CIN 2 or worse lesion in women with HPV-18 infection at baseline was 13.3% (95% CI 5.1–26.8); in women with HPV-16 infection was 10.8% (95% CI 4.4–20.9); in women with HPV-31 infection was 4.2% (95% CI 0.9–11.7); and in women with other high-risk HPV infections was 5.4% (95% CI 2.6–9.7). HPV-18 infection at baseline contributed highest frequency of incident CIN 2 or worse lesions followed by HPV-16 infection; however, other high-risk HPV types were also responsible for substantial number of incident CIN. The elevated risk of CIN2+ disease in the study cohort was non-significant in women with CD4 count <200, possibly because of the small number of cases. Our results emphasize the need for regular cervical cancer screening of HIV-infected women and urgent implementation of cervical cancer screening services in HIV programs in India and other low and middle-income countries.     

Predicting the progression of cervical precursor lesions by human papillomavirus genotyping: A prospective cohort study

Only a subset of cervical precursor lesions progress to cervical cancer and because of the lack of the predictive markers, it cannot be ascertained which lesions will progress or not. To estimate the risk of disease progression associated with human papillomavirus (HPV) genotypes, we followed 570 Japanese women with cytological LSIL (low‐grade squamous intraepithelial lesion) and histological CIN (cervical intraepithelial neoplasia) grade 1–2 lesions (479 CIN 1; 91 CIN 2) at 3 to 4 month intervals for a mean follow‐up period of 39.1 months. At entry, we detected HPV DNA in cervical samples by polymerase chain reaction‐based methodology. Over the period of follow‐up period, 46 lesions progressed to CIN 3 while 362 regressed to normal cytology. Women with multiple HPV infections were more likely to have persistent lesions (hazard ratio [HR] for regression, 0.65; 95% confidence interval [CI], 0.42–1.02; p = 0.07); however, multiple infections did not increase the risk of progression (HR for progression, 1.04; 95% CI, 0.37–2.94; p = 0.94). After adjusting for CIN grade and women's age, HRs for progression to CIN 3 (vs. women with low‐risk types or negative for HPV DNA) varied markedly by HPV genotype: type 16 (11.1, 95% CI: 1.39–88.3); 18 (14.1, 0.65–306); 31 (24.7, 2.51–243); 33 (20.3, 1.78–231); 35 (13.7, 0.75–251); 52 (11.6, 1.45–93.3); 58 (8.85, 1.01–77.6); other high‐risk types (4.04, 0.47–34.7). HPV 45 was not detected in our study subjects. The cumulative probability of CIN 3 within 5 years was 20.5% for HPV 16, 18, 31, 33, 35, 52 and 58; 6.0% for other high‐risk types; 1.7% for low‐risk types (p = 0.0001). In conclusion, type‐specific HPV testing for women with LSIL/CIN 1–2 lesions is useful for identifying populations at increased or decreased risk of disease progression.     

Long‐term HPV type‐specific risks for ASCUS and LSIL: A 14‐year follow‐up of a randomized primary HPV screening trial

Human papillomavirus (HPV) infections result in a significant burden of low‐grade cervical lesions. Between 1997 and 2000, our randomized trial of primary HPV screening enrolled 12,527 women participating in population‐based screening. Women between 32 and 38 years of age (median: 34, interquartile range: 33–37) were randomized to HPV and cytology double testing (intervention arm, n = 6,257 enrolled, n = 5,888 followed‐up) or to cytology, with samples frozen for future HPV testing (control arm, n = 6,270 enrolled, n = 5,795 followed‐up). We estimated the HPV type‐specific, long‐term absolute risks (AR), and population attributable proportions (PAR) for cytological diagnoses of atypical squamous cells of undetermined significance (ASCUS) or low‐grade squamous intraepithelial lesion (LSIL) and for histopathologically diagnosed cervical intraepithelial neoplasia grade 1 (CIN1). The women were followed using comprehensive, nationwide register‐based follow‐up. During a mean follow‐up time of 11.07 years, 886 ASCUS and LSIL lesions were detected, 448 in the intervention arm and 438 in the control arm. Poisson regression estimated the incidence rate ratios (IRRs) of low‐grade lesions by HPV type. The IRRs were strongly dependent on follow‐up time. The IRRs for ASCUS/LSIL associated with high‐risk HPV positivity were 18.6 (95% CI: 14.9–23.4) during the first screening round, 4.1 (95% CI: 2.8–6.2) during the second, 2.6 (95% CI: 1.7–4.1) during the third, and 1.1 (95% CI: 0.7–1.8) for >9 years of follow‐up, with similar declines seen for the individual types. Type 16 contributed consistently to the greatest proportion of ASCUS, LSIL, and CIN1 risk in the population (first screening round PAR: ASCUS: 15.5% (95% CI: 9.7–21.9), LSIL: 14.7% (95% CI: 8.0–20.9), and CIN1: 13.4% (95% CI: 3.2–22.5)), followed by type 31 [8.4% (95% CI: 4.2–12.5) for ASCUS to 17.3% (95% CI: 6.8–26.6) for CIN1]. In summary, most ASCUS/LSIL lesions associated with HPV infection are caused by new HPV infections and most lesions are found during the first screening round.