Reasons for variation in coverage in the NHS cervical screening programme

In order to investigate reasons for variation in coverage of cervical screening, data from standard Department of Health returns were obtained for all Health Authorities for 1998/1999. Approximately 80% of the variation between health authorities is explained by differences in age distribution and area classification. Considerable differences between Health Authority and Office of National Statistics (ONS) population figures in City and Urban (London) areas for the age group 25-29 years and for City (London) for age group 30-34 years, suggest an effect of list inflation in these groups. Coverage as a performance indicator may be more accurately represented using the age range 35-64 years. Using this narrower age range, the percentage of health authorities meeting the 80% 5-year coverage target increases from 87% to 90%.     

The use of digital images to evaluate the interobserver agreement on cervical smear readings in Italian cervical cancer screening

G. Tinacci, A. Biggeri, A. Pellegrini, M.P. Cariaggi, M.L. Schiboni and M. Confortini The use of digital images to evaluate the interobserver agreement on cervical smear readings in Italian cervical cancer screening Objective: The aim of this study was to measure interobserver agreement among cytologists on using a set of digital images. Methods: A set of 90 selected Papanicolaou‐stained cervical smears were digitalized and the digital images circulated among 117 readers, from laboratories spread across almost all Italian regions. Three representative fields of each smear were displayed at 20× and 40× magnification (overall six images for each case). The diagnoses made by the cytologists who provided the images were taken as target diagnoses. Results: The κ values were: very low for the categories atypical squamous cells of undetermined significance (ASC‐US), and atypical squamous cells – cannot exclude high‐grade squamous intraepithelial lesion (ASC‐H); poor for the categories atypical glandular cells (AGC), high‐grade squamous intraepithelial lesion (HSIL) and invasive cancer; and fair to good for the categories negative and low‐grade squamous intraepithelial lesion (LSIL). However, we found a cluster of 42 best concordant readers. The overall κ value and overall weighted κ with the target diagnosis for these 42 readers were 0.45 and 0.66, respectively. This finding is in contrast with the overall κ value and overall weighted κ for the other readers of 0.39 and 0.59, respectively. Conclusions: As this finding is an estimate of the accuracy of the readers, we can infer that it will be very important to reach this level of concordance for all the participating readers. Future effort will facilitate common experiences in order to improve the reproducibility of diagnostic criteria. Digital images could be the key to reach this aim.     

The effects of different sampling techniques on smear quality and the diagnosis of cytological abnormalities in cervical screening

A major cause of false‐negative cervical smears is sampling error. We examined the results obtained with three different instruments in 126 608 smears from general practitioners. The spatula/brush combination yielded the highest proportion of smears showing cytological abnormalities, and the Cervex brush the lowest. Although not a randomized study, this paper highlights the shortcomings of the Cervex brush. We postulate a mechanical deficiency. Diagnostic accuracy rather than a high proportion of good quality smears should dictate the choice of instrument.     

A study of the effect of introducing a restrictive cervical screening policy on laboratory workload and cervical cancer detection rates

This study examines the effect of a change in screening policy on the detection rate of severe dyskaryosis. During 1987 a total of 423 cases of severe dyskaryosis were identified by the Avon Screening Programme. Eleven per cent of these abnormal smears were repeat smears taken without clinical indication within the recommended 5 year recall period (interval smears). In a comparable control group of negative smears 31% were interval smears. Twenty-five per cent of the dyskaryotic interval smears (3% of the total severely dyskaryotic smears) were taken within 3 years of the previous negative smear, compared with 50% of the control group. By discouraging opportunistic smears within 5 years of the previous smear, the laboratory workload could be reduced by 30%, or within 3 years of the previous smear by 15%. There is, however, a risk of 11% and 3% respectively of missing a significant lesion (severe dyskaryosis).     

The preparation of additional smears from a cervical scrape: impact on the rate of detection of cervical neoplasia

The preparation of additional smears from a cervical scrape: impact on the rate of detection of cervical neoplasia It has been known for some time that only a proportion of the cells on the smear-taking device is transferred to the slide. This can give rise to errors in reporting although the smear may have been taken correctly. This study was undertaken to identify a quick and simple method of improving the accuracy of the Papanicolaou test. A conventional smear and five additional smears were obtained from 62 women attending a Genito-Urinary Medicine clinic. The cell content of the conventional smears and the additional smears was compared. Dyskaryotic cells were detected both in the conventional smear and in the first and second additional smears from 22 women. Dyskaryotic cells were detected in the first and second additional smears only in five women. Thus, the conventional smear failed to detect biopsy-confirmed cervical abnormality in these women. A cell count of the first additional smear in the five cases where the conventional smear was negative showed that they contained, on average, 310 dyskaryotic cells. The preparation of one additional cervical smear per cervical scrape could significantly increase the accuracy of the cervical smear test by 11% (P=0.025, McNemar's test).     

Rapid pre-screening of cervical smears as a method of internal quality control in a cervical screening programme

Objective:  To evaluate the performance of rapid pre-screening (RPS) as a method of internal quality control in the cytopathological examination of cervical smears for cervical cancer screening.
Methods:  The sample consisted of 6135 cervical smears submitted to RPS and routine screening (RS) methods. The smears classified as negative in RPS and RS were considered final diagnoses, and were not, therefore, submitted to any additional review. The smears identified as suspect or unsatisfactory according to RPS were analysed separately by two different cytologists irrespective of the diagnosis reached in RS. Smears considered abnormal or unsatisfactory at RS were also reviewed. When both cytologists issued concordant diagnoses, this was considered the final diagnosis. Discordant results were analysed by a third cytologist and a consensus meeting was held to define the final diagnosis.
Results:  Taking abnormalities detected by RS as the denominator, RPS had a sensitivity of 63.0% for the detection of all abnormal smears and 96.7% for high grade squamous intraepithelial lesion (HSIL). When compared with the final diagnosis, sensitivity of RPS for all abnormal smears was 74.9% and for HSIL 95.0%. Of the 529 abnormal smears confirmed in the final diagnosis, 2.15% were detected only by the RPS.
Conclusion:  RPS is an effective alternative method of internal quality control with high sensitivity for the detection of more severe lesions. It also permits monitoring of the laboratory rate of false-negative results, and allows constant evaluation of the performance both of the pre-screening and RS cytologists.     

The cervical smear test: does timing have an effect on sample adequacy?

OBJECTIVE: The aim of this study was to determine the effect of timing of the cervical smear test on sample adequacy. METHODS: Inadequate and negative smears from pre-menopausal women, with a regular menstrual cycle and who were not undertaking any hormone therapy, were selected and re-screened. The inadequate smears were then categorized according to the reasons for the inadequate result. The time of the cycle that the smear was taken was recorded for both inadequate and negative smears. The expected frequency of smears per phase was compared with the observed frequency per phase using the chi-squared statistical test. RESULTS: There was no significant difference between the overall observed and expected rate of the inadequate smears of nine general practitioner (GP) practices (P = 0.886), of GP practice 4 (lowest inadequate rate) (P = 0.610), or GP practice 6 (highest inadequate rate) (P = 0.621) at any phase of the cycle. CONCLUSION: Results show that there is no optimum phase for adequate sample collection, therefore it is suggested that there is no effect of timing of the cervical smear test on sample adequacy, that timing is not a relevant factor in reducing the inadequate smear rate, and restricting smear taking to mid-cycle is unnecessary. (The information regarding last menstrual period/length of cycle from which these conclusions were reached relied upon the accuracy of patient information given to the smear taker.).     

The effect of tamoxifen on cervical squamous maturation in Papanicolaou stained cervical smears of post-menopausal women

Using cervical smears obtained as part of routine gynaecological examinations, a retrospective study of the effects of the drug tamoxifen on squamous epithelial maturation of the cervix of post-menopausal women being treated for advanced breast cancer was made. The degree of squamous epithelial maturation was quantitated by using the Maturation Index and the Maturation Value. Although tamoxifen is a synthetic, non-steroidal compound classified as anti-oestrogenic, the findings indicate that this drug commonly produces a level of squamous maturation indicative of oestrogenic stimulation in Papanicolaou stained cervical smears from post-menopausal patients receiving this drug. Knowledge of the oestrogenic effect of tamoxifen in the cervix can obviate clinical concern about endometrial carcinoma.     

The quality of smear taking training for hospital medical trainees

INTRODUCTION: Training for cervical smear takers in primary care is well established. We aimed to assess the adequacy of training in cervical smear taking among hospital medical trainees. METHOD: An anonymous questionnaire survey was conducted among hospital medical trainees within the North West region of England. The questionnaire assessed the trainees' level of confidence in their knowledge and skills in the theoretical and practical aspects of cervical smear taking, and the training they had received. The standards used were as stated in the National Health Service Cervical Screening Programme Resource Pack for Training Smear Takers (July 1998). These included practical smear taking, pre- and post-test counselling, the background to cervical screening, the National Health Service Cervical Screening Programme, the role of the Health Authority and the laboratory, provision for women with special needs, acceptability, accountability and quality assurance. RESULTS: Seventy-eight per cent of trainees returned the questionnaires. Although all the trainees were confident about taking smears, a significant percentage was concerned about the theoretical and specific issues associated with smear taking such as the care of women with special needs. Only 60.7% had received formal training in practical smear taking. Furthermore, only 48.3% had been formally trained in the clinical management of smears. CONCLUSION: There appears to be an urgent need for formal training in the theory and practice of smear taking and for the standardization of the course content. The introduction of training in liquid-based cytology provides us with a golden opportunity to address this deficit.     

Costs and benefits of cervical screening. I. The costs of the cervical screening programme

In 1991, the average total Health Service cost of a cervical smear, including follow up at the colposcopy clinic, was almost £22.70 in the Perth and Kinross district of Scotland. The average cost per colposcopy clinic visit was £30. The main cost elements were in general practice (55% of total) and the laboratory (33%), and most of the cost was for staff time.     

Implementation of liquid-based cytology in the screening programme against cervical cancer in the County of Funen, Denmark, and status for the first year

As one of the first laboratories in Denmark (and Scandinavia), we have gradually implemented liquid-based cytology into the screening programme against cervical cancer in the County of Funen since 1 June 2001. This paper describes the course of the implementation period in the different steps in the screening programme, and the preliminary results obtained after the first year. We conclude that the new technique has improved the specimen and diagnostic quality. As a result of the reduction of the screening time, the workload in the laboratory is in balance although we have introduced a rapid review as a quality control. Besides, the reduction in the number of repeated cytological tests and follow-up visits at the gynaecologist means a saving for the screening programme as a whole. From our point of view the implementation of ThinPrep method is economically neutral.     

Costs and benefits of cervical screening IV: valuation by women of the cervical screening programme

OBJECTIVES: To assess the value of the cervical smear test to women, taking account of the positive and negative aspects of the cervical screening service. DESIGN: A postal survey. SETTING: Tayside Health Board region of Scotland. PARTICIPANTS: A sample of 2000 women aged 20-59. MAIN OUTCOME MEASURES: Maximum willingness to pay (WTP) for a cervical smear test. RESULTS: Women were prepared to pay 50.20 British pounds per smear on a 3-yearly basis. Willingness to pay was positively related to income, but unrelated to age and whether or not the respondent had previously had a smear. CONCLUSIONS: Previous studies have estimated the cost per screen or cost per life year saved by cervical screening. This study used the economic instrument of WTP to take account of other potential (dis)benefits to women. The value women place on having a smear was more than the cost to the National Health Service (NHS) of providing the service. The output of a WTP study is potentially useful at the policy level. Future work should explore both the value of alternative approaches to cervical screening, and the value of competing health care interventions.     

Improving the NHS cervical screening laboratory performance indicators by making allowance for population age, risk and screening interval

OBJECTIVE: One of the key performance measures in the monitoring of the NHS cervical screening programme is the targeting of laboratories with very high or low percentages (outside the 10th-90th percentile) of adequate smears that have moderate dyskaryosis or worse. These laboratories are assumed to include those laboratories that may have extremes of sensitivity and specificity. A clear limitation with this methodology is that laboratories do not examine smears from women with the same underlying risk, age distribution or screening interval and adjustment for these factors should considerably improve the method. METHODS: This paper describes a method that allows for these confounding variables and a new age-risk-interval adjusted moderate dyskaryosis or worse rate (ARI-adjusted mod+ rate) can be calculated. The adjusted rate is the rate of moderate or worse dyskaryotic smears that the laboratory would have detected had it been screening women with an English 'average' age-risk-interval. All laboratories can therefore be compared using this method. RESULTS: The methodology is illustrated using data from the NHSCSP South West Region. The particularly low percentage of moderate or worse smears detected by one or two laboratories can be shown to be due to a local screened population with a very low risk because of a high mean age, relatively short screening interval and census variables associated with a low risk, rather than any under-calling by the associated laboratories. CONCLUSIONS: The ARI-adjusted mod+ rate requires to be calculated for all laboratories in England if it is to be used as a primary performance indicator. Alternatively, it can be used to further examine laboratories that are deemed to be outliers using the current methodology.     

Effect of regular 3-yearly screening on the incidence of cervical smears: the Leiden experience

The effect of regular 3-yearly screening over a period of 12 years, on the incidence of cervical cancer in 25,000 women aged 35-54 years, is examined. The rate of squamous cell carcinoma decreased from 0.38 per 1000 women in the first round to zero in the fourth round. Similarly, the rate of carcinoma in situ declined from 1.69 per 1000 women in the first round to 0.35 per 1000 in the fourth round. The rates of severe dysplasia showed no decline. Cytologic under diagnosis of carcinoma-in-situ and cervical carcinoma increased with each round. Widowed and divorced women and those living in urban areas were identified as high risk groups.     

Review of negative and low‐grade cervical smears in women with invasive cervical cancer after the first 3 years of the national cervical screening programme in Slovenia

A. Repše‐Fokter, A. Pogačnik, V. Snoj, M. Primic‐Žakelj and M. S. Fležar
Review of negative and low‐grade cervical smears in women with invasive cervical cancer after the first 3 years of the national cervical screening programme in Slovenia Objective: The purpose of the study was to perform a national review of negative, low‐grade and inadequate smears reported during the latest screening period before cervical cancer diagnosis in 2006, after the first 3 years of the screening programme. Methods: Among 162 new cervical cancer cases there were 47 (29%) without previous cytology, 47 (29%) with one high‐grade smear prior to diagnosis and 68 (42.0%) with at least one previous negative, low‐grade, atypical or inadequate smear 1–40 months before diagnosis. Of the latter 68 cases, 37 patients with 59 smears (together with 118 control slides) were included in the review as 31 had smears reported at laboratories no longer operating. Findings were related to the last cytology report before diagnosis as well as to histological type and stage of the cancer. Results: In our study group, 19 (51%) of 37 patients had squamous cell carcinoma, 15 (41%) adenocarcinoma and 3 (8%) adenosquamous carcinoma, compared with 121 (75%), 26 (16%), 12 (7%), respectively, and 3 (2%) other types, for all carcinomas. Twenty‐one of 37 women also had high‐grade cytology prior to diagnosis of cancer. Women with previous cytology (with or without recent high‐grade smears) were more likely to have stage I cancers than those without cytology (P < 0.0001). The expert group upgraded 17/33 smears in the patients with squamous carcinomas, which was more than in those with adeno‐ and adenosquamous carcinomas (5/24, P < 0.05). Conclusion: As expected, a higher proportion of smears preceding adenocarcinomas were true negative. Under‐diagnosed smears were not related to cancer stage or last cytology report before diagnosis.     

Trends in incidence of,and mortality from,cervical lesions in Ireland: Baseline data for future evaluation of the national cervical screening programme

AimTo investigate incidence and mortality trends for cervical lesions in Ireland in the period 1994–2008.MethodsWe used data from the National Cancer Registry, Ireland and national death registration data to calculate age-standardised rates for the periods of interest. We used standardised rate ratios to test whether incidence was associated with socio-demographic variables and used Joinpoint to examine trends by morphology grouping.ResultsIncidence of cervical cancer and cervical intraepithelial neoplasia (CIN3) rose over the period 1994–2008. The annual percentage change for cervical cancer was 1.8% and that for CIN3 was 3.8%. Women resident in the most deprived areas had invasive cervical cancer incidence almost twice as high as those resident in the least deprived areas (standardised rate ratio (SRR) = 1.8). Comparing incidence in Ireland to England and Wales, Northern Ireland and Scotland in the three years 2005–2007, the SRRs (other areas vs. Ireland) were 0.70, 0.88 and 0.84 respectively. Cervical cancer rates have fallen in these countries in the same period that there is a rise demonstrated in Ireland.ConclusionIncidence rates of cervical cancer rose in Ireland steadily, albeit modestly, during 1994–2008, most likely due to long-term changes in patterns of sexual behaviour and contraceptive use. A more pronounced rise in CIN3 rates point to considerable levels of opportunistic screening during this period. Mortality rates have changed little over the past four decades, in contrast to trends in countries with well-organised screening programmes.     

DNA quantification is technically feasible and of value in cervical smear samples: possible applications for determination of progression in low grade dyskaryosis

This study evaluates the feasibility of DNA analysis of cervical intraepithelial neoplasia III (CIN III) lesions on cervical smear and formalin-fixed paraffin-embedded tissue (FFPET) blocks with a view to extending this type of analysis to milder grades of dyskaryosis. DNA ploidy was determined by image analysis using a CAS 200 Image Analyser. Seventeen patients with a diagnosis of CIN III were studied. Results show that all smear and tissue samples were non-diploid with nine aneuploid and eight tetraploid lesions. In 6/7 patients whose smears and corresponding biopsies were examined there was complete agreement as to the DNA profile. We conclude that DNA quantification is technically feasible in archival, routinely prepared cervical smears. This technique should now be applied to CINI and CINII cervical smears to determine if it is of value in identifying those lesions that will progress to CIN III. This study is particularly timely with the possibility in the near future of estimation of ploidy by image analysis using instruments such as the Highly Optimized Microscope Environment (HOME) system.     

Prospective study of PAPNET: review of 25656 Pap smears negative on manual screening and rapid rescreening

In this prospective study, 27,014 Pap smears were selected for PAPNET review on the request of the referring practitioner or patient. Smears that were negative on routine manual screening were submitted for rapid rescreening. Smears considered normal after these two manual screens (n = 25,656) were reviewed using the PAPNET testing system. Routine manual screening identified 1340 (4.96%) of the smears as abnormal, and a further 18 (0.07%) abnormalities were detected by rapid rescreening. PAPNET review identified an additional 102 (0.4%) abnormal smears, including 10 histologically confirmed high grade lesions. The use of PAPNET testing following routine manual screening and rapid rescreening in tandem, enables cytologists to detect additional diagnostically significant abnormalities and reduce the rate of false-negative smears.     

A pilot study of cervical screening in an inner city area—lessons for a national programme

The objectives of this study were to examine aspects of organization of a proposed national screening programme based in general practice. The target population of women aged 25–59 years and their general practitioners (GPs), in a defined inner city area, was identified from a population register of persons eligible for free medical services; a computerized system was developed for invitations and record linkage of cytology results. Smears were examined in one laboratory and follow up of women with abnormal smears was undertaken by one gynaecologist. A random sample of non‐responders was surveyed by questionnaire. Response following two invitations was only 20%. Practices with male doctors only had significantly lower reponse rates ( P <0.001) than those with a female doctor/nurse. A survey of non‐responders showed that over 20% of addresses were incorrect and 16% of those interviewed were ineligible for smear tests. A preference for a female to undertake smears was expressed by 67%, and 77% believed that the purpose of the cervical smear was to detect cancer. An accurate population register, health promotion, support for GP practices, provision of alternative venues for smear tests, development of computer systems, accurate data entry and fail‐safe follow up are aspects of a cervical screening service which must be addressed prior to setting up a national service.