Women who participate in spontaneous screening are not at higher risk for cervical cancer than women who attend programme screening

Impact of opportunistic testing in a systematic cervical cancer screening program: a nationwide registry study

BACKGROUND

Systematic screening for precancerous cervical lesions has resulted in decreased incidence and mortality of cervical cancer. However, even in systematic screening programs, many women are still tested opportunistically. This study aimed to determine the spread of opportunistic testing in a systematic cervical cancer screening program, the impact of opportunistic testing in terms of detecting cytological abnormalities and examine the associations between sociodemography and opportunistic testing.

METHODS

A nationwide registry study was undertaken including women aged 23-49 years (n = 807,624) with a cervical cytology between 2010 and 2013. The women were categorised into: 1) screening after invitation; 2) routine opportunistic testing, if they were either tested more than 9 months after the latest invitation or between 2.5 years and 3 years after the latest cervical cytology and 3) sporadic opportunistic testing, if they were tested less than 2.5 years after the latest cervical cytology. Cytological diagnoses of women in each of the categories were identified and prevalence proportion differences (PPD) and 95% confidence intervals (CIs) were used to explore group differences. Associations between sociodemography and undergoing opportunistic testing were established by multinomial logistic regression.

RESULTS

In total, 28.8% of the cervical cytologies were due to either routine (20.7%) or sporadic (8.1%) opportunistic testing. Among women undergoing routine opportunistic testing, a larger proportion had high-grade squamous intraepithelial abnormalities than invited women (PPD: 0.6%, 95 % CI: 0.03-1.17%). A similar proportion of cytological abnormalities among women undergoing sporadic opportunistic testing and invited women was found. In multivariate analyses, younger age, being single or a social welfare recipient and residence region (North Denmark) were especially associated with opportunistic testing (routine or sporadic).

CONCLUSIONS

One fourth of cervical cytologies in this study were collected opportunistically. Compared to invited women, women undergoing routine opportunistic testing were more likely to be diagnosed with abnormal cytologies. Hence, routine opportunistic testing might serve as an important supplement to the systematic screening program by covering non-participating women who may otherwise be tested with a delay or not tested at all. Among women tested more often than recommended (sporadic testing), no benefits in terms of detecting more cytological abnormalities were identified.

Cervical cancer screening in the United States and the Netherlands: a tale of two countries

CONTEXT

This article compares cervical cancer screening intensity and cervical cancer mortality trends in the United States and the Netherlands to illustrate the potential of cross-national comparative studies. We discuss the lessons that can be learned from the comparison as well as the challenges in each country to effective and efficient screening.

METHODS

We used nationally representative data sources in the United States and the Netherlands to estimate the number of Pap smears and the cervical cancer mortality rate since 1950. The following questions are addressed: How do differences in intensity of Pap smear use between the countries translate into differences in mortality trends? Can population coverage rates (the proportion of eligible women who had a Pap smear within a specified period) explain the mortality trends better than the total intensity of Pap smear use?

FINDINGS

Even though three to four times more Pap smears per woman were conducted in the United States than in the Netherlands over a period of three decades, the two countries' mortality trends were quite similar. The five-year coverage rates for women aged thirty to sixty-four were quite comparable at 80 to 90 percent. Because screening in the Netherlands was limited to ages thirty to sixty, screening rates for women under thirty and over sixty were much higher in the United States. These differences had consequences for age-specific mortality trends. The relatively good coverage rate in the Netherlands can be traced back to a nationwide invitation system based on municipal population registries. While both countries followed a "policy cycle" involving evidence review, surveillance of screening practices and outcomes, clinical guidelines, and reimbursement policies, the components of this cycle were more systematically linked and implemented nationwide in the Netherlands than in the United States. To a large extent, this was facilitated by a public health model of screening in the Netherlands, rather than a medical services model.

CONCLUSIONS

Cross-country studies like ours are natural experiments that can produce insights not easily obtained from other types of study. The cervical cancer screening system in the Netherlands seems to have been as effective as the U.S. system but used much less screening. Adequate coverage of the female population at risk seems to be of central importance.

Cytology history preceding cervical cancer diagnosis: a regional analysis of 286 cases

Background:

Despite programmed screening in the Netherlands, the decrease in incidence of cervical carcinoma lags behind. We analysed screening results preceding carcinoma cases, timeliness in case of follow-up, and FIGO (International Federation of Gynaecology and Obstetrics) stages as efficiency parameters for screening were taken.

Methods:

We analysed 286 women with cervical cancer between 2005 and 2007 for cytology history preceding carcinoma, hierarchically arranging cytology history (if present) into three groups: ‘screened’, ‘work-up’, and ‘underscreened’ (>6 yrs before diagnosis). For screen- and work-up smears, we analysed timeliness. FIGO stage was measured in relation to cytology history.

Results:

A total of 105 out of 286 (36.7%) women with cervical carcinoma were screened preceding the diagnosis. Delayed time intervals in case of abnormal cytology were 43.5% for borderline/mild dyskaryosis (BMD) and 38.0% for BMD (moderate dyskaryosis or worse; P=0.51). A total of 108 out of 286 (36.4%) women were underscreened, and 73 out of 286 (25.5%) were unscreened. Advanced carcinoma or FIGO stage ⩾2B in screened women was 16.0 vs 48.7% in work-up, underscreened, or unscreened (P<0.001).

Conclusion:

Women with cervical cancer are underscreened and have poor timeliness in case of abnormal cytology. Being un- or underscreened correlates significantly with higher cervical cancer stages, especially in older women (aged ⩾49 years; P<0.001). Improvement of attendancy is needed to meet the standard of quality for screening programmes.

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.

Ontario Cervical Cancer Screening Clinical Practice Guidelines

OBJECTIVE

To develop clinical practice guidelines for cervical screening and the primary management of abnormal cytology in Ontario, using an established methodological process.

DATA SOURCES

Primary data sources were relevant articles listed in the Medline (1998 to July 2004), Embase (1998 to July 2004), and Cochrane Library (2004, Issue 2) databases.

STUDY SELECTION

Studies addressing quality or the optimization of cervical screening were considered eligible in the systematic review of the evidence. Specifically, clinical practice guidelines, technology assessments, systematic reviews, and randomized controlled trials were of primary interest. Given the variability of the data, other information sources were considered eligible if there was a demonstrated gap in the published literature.

DATA EXTRACTION

Data were identified and extracted by a methodologist and reviewed by four authors. Results were reviewed and discussed by members of an expert working group consisting of a diverse group of health professionals with expertise in cervical cancer. Data audits were conducted by independent reviewers.

DATA SYNTHESIS

recommendations with evidence ratings were developed through a review of the evidence with expert consensus and were approved by more than 80% of 40 external practitioners who reviewed the document and responded to a standardized survey.

CONCLUSION

The development of comprehensive recommendations on cervical screening in Ontario was feasible using a rigorous methodological process. Recommendations for practice are provided.

Long-term protective effect of high-risk human papillomavirus testing in population-based cervical screening

We prospectively evaluated the 5-year predictive values of adding high-risk human papillomavirus (hrHPV) testing to cytology for the detection of ⩾cervical intraepithelial neoplasia (CIN)3 lesions in a population-based cohort of 2810 women. At baseline, nine (0.3%) women had prevalent lesions ⩾CIN3, all being hrHPV positive. After 5 years of follow-up, four (6.5%) of the 62 hrHPV-positive women with normal cytology developed lesions ⩾CIN3, vs only one (0.05%) of the 2175 hrHPV-negative women with normal cytology. High-risk human papillomavirus testing or combined screening revealed a much higher sensitivity, at the cost of a small decrease in specificity, and a higher negative predictive value for the detection of lesions ⩾CIN3 till the next screening round (5 years) than cytology alone.

The Dutch CISOE-A framework for cytology reporting increases efficacy of screening upon standardisation since 1996

AIM

To describe the effect of introducing the CISOE-A framework for reporting cervical cytology results, including changes in repeat and referral advice in the Netherlands, on the efficacy of the screening programme. Changes in the distribution of cytological results, the detection rate of cervical intraepithelial neoplasia (CIN) lesions, and the detection rate of squamous cervical carcinoma are reported.

METHODS

The results of all gynaecology cytological and histological examinations, as registered in the nationwide database for histopathology and cytopathology (PALGA) from 1990 to 2000, were retrieved from seven laboratories in the greater Amsterdam area.

RESULTS

After the introduction of the CISOE-A classification, cytological results with equivocal diagnoses decreased significantly from 11.3% to 2.6%, without an increase in the percentages of moderate dyskaryosis or worse. During the study period, the detection rate of histologically diagnosed high grade CIN lesions increased significantly from 4.1 to 6.4/1000 smears, whereas there was no change in the detection rates of low grade lesions or invasive cervical cancer.

CONCLUSIONS

The introduction of the new CISOE-A classification system resulted in a substantial decrease of equivocal results and repeat recommendations, without a decrease in the detection rate of high grade lesions, making the screening programme more efficacious.

Assessing the evidence for organised cancer screening programmes

The aim of this study was to review the evidence in the literature for organised cancer screening programmes. A Medline search for publications related to organised cancer screening programmes and their components was done. While there is a broad descriptive literature on various cancer screening programmes, there are few published studies that evaluate the impact of organised cancer screening. Most of the evidence to date is from Scandinavian cervical and breast cancer screening programmes. There is a moderate amount of literature that evaluates specific components of cancer screening programmes (such as quality control and recruitment). There is a substantial body of literature on organised cancer screening programmes. However, the studies tend to describe organised screening programmes rather than evaluate their effectiveness relative to opportunistic screening. Furthermore, most studies focus on individual components of organised screening programmes, rather than on the programmes as a whole. More research is needed that directly compares organised with opportunistic cancer screening.