Feja J. Voorhorst

Relation of human papilloma virus status to cervical lesions and consequences for cervical-cancer screening: a prospective study

BACKGROUND A relation has been established between infection with high-risk types of human papillomavirus and development of cervical cancer. We investigated a role for testing for human papillomavirus as part of cervical-cancer screening. METHODS We monitored by cytology, colposcopy, and testing for high-risk human papillomavirus 353 women referred to gynaecologists with mild to moderate and severe dyskaryosis. The median follow-up time was 33 months. At the last visit we took biopsy samples. Our primary endpoint was clinical progression, defined as cervical intraepithelial neoplasia (CIN) 3, covering three or more cervical quadrants on colposcopy, or a cervical-smear result of suspected cervical cancer. FINDINGS 33 women reached clinical progression. All had persistent infection with high-risk human papillomavirus. The cumulative 6-year incidence of clinical progression among these women was 40% (95% CI 21-59). In women with end histology CIN 3, 98 (95%) of 103 had persistent infection with high-risk human papillomavirus from baseline. Among women with mild to moderate dyskaryosis at baseline, a second test for human papillomavirus at 6 months predicted end histology CIN 3 better than a second cervical smear. INTERPRETATION Persistent infection with high-risk human papillomavirus is necessary for development and maintenance of CIN 3. All women with severe dyskaryosis should be referred to gynaecologists, whereas women with mild to moderate dyskaryosis should be referred only after a second positive test for high-risk human papillomavirus at 6 months.

Human papillomavirus DNA testing for the detection of cervical intraepithelial neoplasia grade 3 and cancer: 5-year follow-up of a randomised controlled implementation trial.

BACKGROUND Tests for the DNA of high-risk types of human papillomavirus (HPV) have a higher sensitivity for cervical intraepithelial neoplasia grade 3 or worse (CIN3+) than does cytological testing, but the necessity of such testing in cervical screening has been debated. Our aim was to determine whether the effectiveness of cervical screening improves when HPV DNA testing is implemented. METHODS Women aged 29-56 years who were participating in the regular cervical screening programme in the Netherlands were randomly assigned to combined cytological and HPV DNA testing or to conventional cytological testing only. After 5 years, combined cytological and HPV DNA testing were done in both groups. The primary outcome measure was the number of CIN3+ lesions detected. Analyses were done by intention to treat. This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN20781131. FINDINGS 8575 women in the intervention group and 8580 in the control group were recruited, followed up for sufficient time (> or =6.5 years), and met eligibility criteria for our analyses. More CIN3+ lesions were detected at baseline in the intervention group than in the control group (68/8575 vs 40/8580, 70% increase, 95% CI 15-151; p=0.007). The number of CIN3+ lesions detected in the subsequent round was lower in the intervention group than in the control group (24/8413 vs 54/8456, 55% decrease, 95% CI 28-72; p=0.001). The number of CIN3+ lesions over the two rounds did not differ between groups. INTERPRETATION The implementation of HPV DNA testing in cervical screening leads to earlier detection of CIN3+ lesions. Earlier detection of such lesions could permit an extension of the screening interval.

Distribution of 37 mucosotropic HPV types in women with cytologically normal cervical smears: the age-related patterns for high-risk and low-risk types.

Before guidelines can be set for the use of high‐risk human papillomavirus (HR HPV) testing in cervical cancer screening and vaccine preparation, age‐related prevalence of HR HPV types in cytologically normal smears has to be known. Therefore, in a cross‐sectional study the prevalence of 37 different HPV genotypes and putatively unidentified HPV types was determined in 3,305 cytologically normal cervical smears from the general female population (15–69 years of age) using an HPV general primer GP5+/bioGP6+ mediated PCR assay. Subsequently, HPV‐positive cervical smears were typed for 19 HR and 18 low‐risk (LR) HPVs with an enzyme immunoassay using HPV type‐specific oligoprobes in cocktails and individually, respectively. Overall, −HR and −LR HPV prevalences appeared to be of 4.6%, 3.3%, and 1.0%, respectively. Twenty‐six different HPV types were detected in the 152 HPV‐positive samples, the most prevalent types being HPV 16, 31, and 18. With regard to age, a peak prevalence of 19.6% for all HPVs was found in women 25–29 years of age, which declined to a mean of 4.3% in women over 30 years. With regard cytologically normal cervical smears (n = 3,011) of women participating in the population‐based screening program in the Netherlands (30 to 60 years), all HR HPVs showed decreased occurrence with increasing age, whereas the prevalence of LR HPV types remained constant. We suggest that screening for abnormal cytology implies screening for HR HPV infections and the subsequent treatment results in a decline of HR HPV prevalence in contrast to LR HPV prevalence during the years of screening. Int. J. Cancer 87:221–227, 2000.

Human papillomavirus 16 load in normal and abnormal cervical scrapes: an indicator of CIN II/III and viral clearance.

The relation between human papillomavirus type 16 (HPV 16) viral load in cervical scrapes and development of high‐grade cervical intraepithelial neoplasia (CIN II or III) was studied in a nested case‐control study of women with normal cytology (group A) and in a cohort of women with abnormal cytology (group B). HPV 16 DNA load was determined using a quantitative real‐time PCR assay. In group A, case women (women with CIN II/III, n = 12) had a significantly higher viral load than control women (women with CIN ≤ I, n = 47). This resulted in an increased relative risk of women with the 50% highest viral load for development of CIN II/III (OR 7.7; CI 1.6–33). In group B, women with CIN II/III (n = 38) had a significantly higher viral load than women with CIN ≤ I (n = 25). Women with the 50% highest viral load had an increased relative risk of CIN II/III (OR 3.2; CI 1.1–9.3) and a decreased chance of both viral clearance and cytologic regression. Our data suggest that in women with normal cytology an increased HPV 16 load confers an increased risk of developing a CIN lesion. A sustained high viral load is subsequently informative for progression to a high‐grade CIN lesion.

POBASCAM, a population‐based randomized controlled trial for implementation of high‐risk HPV testing in cervical screening: Design, methods and baseline data of 44,102 women

Cytological cervical screening is rather inefficient because of relatively high proportions of false negative and false positive smears. To evaluate the efficiency of high‐risk human papillomavirus (hrHPV) testing, by GP5+/6+ PCR‐enzyme immunoassay (EIA), in conjunction with cytology (Intervention Group) to that of the classical cytology (Control Group), we initiated the Population Based Screening Study Amsterdam (POBASCAM). POBASCAM is a population‐based randomized controlled trial for implementation of hrHPV testing in cervical screening. The outcome measure is the proportion of histologically confirmed ≥CIN3 lesions in each study arm up to and including the next screening round after 5 years. We present the design, methods and baseline data of POBASCAM. When, in the next 5 years, the follow‐up will be completed, the data obtained will be used in model studies, including a cost‐effectiveness study, to advise the Dutch Ministry of Public Health in deciding whether cervical screening should be based on combined hrHPV and cytology testing instead of cytology alone. Between January 1999 and September 2002, 44,102 women (mean age = 42.8 years; range = 29–61) that participated in the regular Dutch screening program were included in our study. In the Intervention Group the distribution of cytology and hrHPV by cytology class was as follows: normal cytology 96.6% (3.6% hrHPV positive); borderline and mild dyskaryosis (BMD) 2.5% (34.6% hrHPV positive); and moderate dyskaryosis or worse (>BMD) 0.8% (88.3% hrHPV positive), i.e., 0.4% moderate dyskaryosis (82.9% hrHPV positive), 0.3% severe dyskaryosis (92.5% hrHPV positive), 0.1% carcinoma in situ (95.2% hrHPV positive), <0.1% suspected for invasive cancer (hrHPV positive 100.0%). In the Control Group 96.5% of the women had normal cytology, 2.4% BMD and 0.8% >BMD, i.e., 0.4% moderate dyskaryosis, 0.3% severe dyskaryosis, 0.1% carcinoma in situ, <0.1% suspected for invasive cancer. The presence of hrHPV was age‐dependent, decreasing from 12.0% at 29–33 years to 2.4% at 59–61 years. Among women with a positive hrHPV test, the prevalence of BMD was age‐dependent ranging from 20.2% at 29–33 years to 7.8% at 54–58 years. In contrast, the risk of >BMD of 13.7% among women with a positive hrHPV test was not age‐dependent. Our study indicates that large‐scale hrHPV testing by GP5+/6+ PCR‐EIA in the setting of population‐based cervical screening is practically feasible, is accepted by both participating women and general practitioners and yields highly reproducible results.

PCR-based high-risk HPV test in cervical cancer screening gives objective risk assessment of women with cytomorphologically normal cervical smears

Cervical‐cancer screening programmes using cytomorphological criteria could be more efficient if the screening included objective individual risk factors for women with normal cytology, such as a test for high‐risk human papillomavirus (HPV). The value of a PCR‐based test for high‐risk HPV types was studied in a cohort of 1622 women presenting in a routine biannual population‐based screening programme. Women were included in the study when they had no previous history of cervical dysplasia; and their initial Pap smear was read as normal (Pap 1 or 2). The mean age of the women was 42 years (range 34–54 years) and mean follow‐up time was 40 months (range 5–73 months). Women were referred for colposcopically directed biopsies if they had had 2 successive cervical smears read as Pap 3a (mild to moderate dyskaryosis) or one read as ≥ Pap 3b (severe dyskaryosis). Women with histologically confirmed cervical intraepithelial neoplasia grade III (CIN III) were considered positive cases. All women were tested for 14 high‐risk HPV genotypes. Of the 86 high‐risk HPV‐positive women, 6 developed CIN III, whereas only 1 of the 1536 HPV‐negative women did. The women with normal Pap smears containing high‐risk HPV genotypes were 116 times (95% Cl, 13–990) more at risk of developing CIN III, in contrast to women without high‐risk HPV. These results support the view that the interval between successive smears in cervical‐cancer screening can be increased considerably for women with cytomorphologically normal and high‐risk HPV‐negative cervical smears as determined by PCR.

HPV testing on self collected cervicovaginal lavage specimens as screening method for women who do not attend cervical screening: cohort study.

Objective To determine whether offering self sampling of cervicovaginal material for high risk human papillomavirus (HPV) testing is an effective screening method for women who do not attend regular cervical screening programmes. Design Cohort study (the PROHTECT trial). Settings Noord-Holland and Flevoland regions of the Netherlands, December 2006 to December 2007, including 13 laboratories, gynaecologists, and more than 800 general practitioners. Participants 28 073 women who had not responded to two invitations to the regular cervical screening programme: 27 792 women were assigned to the self sampling group and invited to submit a self collected cervicovaginal sample for HPV testing; 281 were assigned to the recall control group and received a second re-invitation for conventional cytology. Intervention Women with a positive result on the high risk HPV test on their self sample material were referred to their general practitioner. Women with abnormal results on cytology were referred for colposcopy. Women with normal results on cytology were re-evaluated after one year by cytology and high risk HPV testing and referred for colposcopy if either result was positive. Main outcome measures Attendance rate in both groups and yield of cervical intraepithelial neoplasia grade II/III or worse (≥CIN II/≥CIN III) in self sampling responders. Results The compliance rate in the self sampling group was significantly higher than in the control group (crude 26.6% v 16.4%, P<0.001; adjusted 27.5% v 16.6%, P<0.001). The number of detected ≥CIN II and ≥CIN III lesions in self sampling responders was 99 (1.3%) and 76 (1.0%), respectively. Self sampling responders who had not participated in the previous round of screening (43%) had increased relative risks of ≥CIN II (2.04, 95% confidence interval 1.27 to 3.28) and ≥CIN III (2.28, 1.31 to 3.96) compared with self sampling women who had been screened in the previous round (57%). Conclusions Offering self sampling by sending a device for collecting cervicovaginal specimens for high risk HPV testing to women who did not attend regular screening is a feasible and effective method of increasing coverage in a screening programme. The response rate and the yield of high grade lesions support implementation of this method for such women. Trial registration ISRCTN45527158.

Cytological regression and clearance of high-risk human papillomavirus in women with an abnormal cervical smear.

We studied the natural course of high-risk human papillomavirus (HPV) infection and cytological regression in women referred for colposcopy because of abnormal cervical smears. We found that high-risk HPV clearance preceded regression of cervical lesions by an average of 3 months. The cumulative 1-year rate of cytological regression was similar in women with mild and moderate dyskaryotic cervical smears. Thus, retesting of high-risk HPV after 6 months in women with mild to moderate dyskaryosis predicts cytological regression.

The natural course of asymptomatic Chlamydia trachomatis infections: 45% clearance and no development of clinical PID after one-year follow-up

The natural course of asymptomatic Chlamydia trachomatis infections in women was studied during one year in a cohort based nested case-control study. Healthy women (n = 744, from four company health services in Amsterdam) with a medical check-up prior to job engagement were included. C. trachomatis-positive women (n = 30, cases) and a randomly selected control group of C. trachomatis-negative women (n = 186, controls) were followed for one year. Urine specimens (at one, six and 12 months) were analysed for the presence of C. trachomatis-DNA and the C. trachomatis-serovars, and questionnaires were filled in. The C trachomatis prevalence and natural course in relation to demographic and sexual characteristics after one, six and 12 months were studied. The main outcome measures were 1) the prevalence of C. trachomatis using urine specimens; 2) self-reported complaints; 3) clinical symptoms reported to the coordinating physicians. The prevalence of asymptomatic C. trachomatis infections was 4% and there was no correlation with demographic and sexual characteristics. The person/year clearance rate was 44.7% per year. None of the C. trachomatis-positive women developed clinical symptoms or used C. trachomatis specific antibiotic treatment. Women with or without an asymptomatic infection had the same number of self-reported urogenital complaints during follow-up. In persisting infections twice as many C. trachomatis-serovar E infections were detected as compared to clearing infections. Our findings showed that almost half of the asymptomatic C. trachomatis infections in women cleared during one year of follow-up and none developed clinical pelvic inflammatory disease (PID), which is a much lower figure than previously suggested. Therefore these data are important for cost effectiveness calculations in screening programmes for asymptomatic C. trachomatis infections.

Addition of high-risk HPV testing improves the current guidelines on follow-up after treatment for cervical intraepithelial neoplasia

We assessed a possible role for high-risk human papillomavirus (HPV) testing in the policy after treatment for cervical intraepithelial neoplasia (CIN) 2 or 3 (moderate to severe dysplasia). According to the Dutch guidelines follow-up after treatment consists of cervical cytology at 6, 12 and 24 months. Colposcopy is only performed in case of abnormal cervical cytology. In this observational study 184 women treated for CIN 2 or 3 were prospectively monitored by cervical cytology and high-risk HPV testing 3, 6, 9, 12 and 24 months after treatment. Post-treatment CIN 2/3 was present in 29 women (15.8%). A positive high-risk HPV test 6 months after treatment was more predictive for post-treatment CIN 2/3 than abnormal cervical cytology (sensitivity 90% and 62% respectively, with similar specificity). At 6 months the negative predictive value of a high-risk HPV negative, normal smear, was 99%. Largely overlapping, partly different groups of women with post-treatment CIN 2/3 were identified by HPV testing and cervical cytology. Based on these results we advocate to include high-risk HPV testing in monitoring women initially treated for CIN 2/3. In case of a high-risk HPV positive test or abnormal cervical cytology, colposcopy is indicated. All women should be tested at 6 and 24 months after treatment and only referred to the population-based cervical cancer screening programme when the tests are negative on both visits.