Evaluation of mammographic surveillance services in women aged 40-49 years with a moderate family history of breast cancer: a single-arm cohort study

BACKGROUND

Women with a significant family history of breast cancer are often offered more intensive and earlier surveillance than is offered to the general population in the National Breast Screening Programme. Up to now, this strategy has not been fully evaluated.

OBJECTIVE

To evaluate the benefit of mammographic surveillance for women aged 40-49 years at moderate risk of breast cancer due to family history. The study is referred to as FH01.

DESIGN

This was a single-arm cohort study with recruitment taking place between January 2003 and February 2007. Recruits were women aged < 50 years with a family history of breast or ovarian cancer conferring at least a 3% risk of breast cancer between ages 40 and 49 years. The women were offered annual mammography for at least 5 years and observed for the occurrence of breast cancer during the surveillance period. The age group 40-44 years was targeted so that they would still be aged < 50 years after 5 years of surveillance.

SETTING

Seventy-four surveillance centres in England, Wales, Scotland and Northern Ireland.

PARTICIPANTS

A total of 6710 women, 94% of whom were aged < 45 years at recruitment, with a family history of breast cancer estimated to imply at least a 3% risk of the disease between the ages of 40 and 50 years.

INTERVENTIONS

Annual mammography for at least 5 years.

MAIN OUTCOME MEASURES

The primary study end point was the predicted risk of death from breast cancer as estimated from the size, lymph node status and grade of the tumours diagnosed. This was compared with the control group from the UK Breast Screening Age Trial (Age Trial), adjusting for the different underlying incidence in the two populations.

RESULTS

As of December 2010, there were 165 breast cancers diagnosed in 37,025 person-years of observation and 30,556 mammographic screening episodes. Of these, 122 (74%) were diagnosed at screening. The cancers included 44 (27%) cases of ductal carcinoma in situ. There were 19 predicted deaths in 37,025 person-years in FH01, with an estimated incidence of 6.3 per 1000 per year. The corresponding figures for the Age Trial control group were 204 predicted deaths in 622,127 person-years and an incidence of 2.4 per 1000 per year. This gave an estimated 40% reduction in breast cancer mortality (relative risk = 0.60; 95% confidence interval 0.37 to 0.98; p = 0.04).

CONCLUSIONS

Annual mammography in women aged 40-49 years with a significant family history of breast or ovarian cancer is both clinically effective in reducing breast cancer mortality and cost-effective. There is a need to further standardise familial risk assessment, to research the impact of digital mammography and to clarify the role of breast density in this population.

TRIAL REGISTRATION

National Research Register N0484114809.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 11. See the HTA programme website for further project information.

Standardization of Gleason grading among 337 European pathologists

AIMS

  The 2005 International Society of Urological Pathology (ISUP) modification of Gleason grading recommended that the highest grade should always be included in the Gleason score (GS) in prostate biopsies. We analysed the impact of this recommendation on reporting of GS 6 versus 7.

METHODS AND RESULTS

  Fifteen expert uropathologists reached two-thirds consensus on 15 prostate biopsies with GS 6-7 cancer. Eighty-five microphotographs were graded by 337 of 617 members of the European Network of Uropathology (ENUP), representing 19 countries. There was agreement between expert and majority member GS in 12 of 15 cases, while members upgraded in three cases. Among members and the expert consensus, a GS >6 was assigned by 64.5% and 60%, respectively. Mean member GS was higher than consensus GS in nine of 15 cases. A Gleason pattern (GP) 5 was reported by 0.3-5.6% in 10 cases. Agreement between consensus and member GS was 58.2-89.3% (mean 71.4%) in GS 6 cases and 46.3-63.8% (mean 56.4%) in GS 7 cases (P = 0.009).

CONCLUSIONS

  While undergrading of prostate cancer used to be prevalent, some now tend to overgrade. Minimum diagnostic criteria for GP 4 and 5 in biopsies need to be better defined. Image libraries reviewed by experts may be useful for standardization.

Breast cancer mortality in mammographic screening in Europe: a review of incidence-based mortality studies

OBJECTIVES

To estimate the impact of service mammography screening on breast cancer mortality using European incidence-based mortality (IBM) studies (or refined mortality studies). IBM studies include only breast cancer deaths occurring in women with breast cancer diagnosed after their first invitation to screening.

METHODS

We conducted a literature review and identified 20 publications based on IBM studies. They were classified according to the method used for estimating the expected breast cancer mortality in the absence of screening: (1) women not yet invited; (2) historical data from the same region as well as from historical and current data from a region without screening; and (3) historical comparison group combined with data for non-participants.

RESULTS

The estimated effect of mammography screening on breast cancer mortality varied across studies. The relative risks were 0.76-0.81 in group 1; 0.75-0.90 in group 2; and 0.52-0.89 in group 3. Study databases overlapped in both Swedish and Finnish studies, adjustment for lead time was not optimal in all studies, and some studies had other methodological limitations. There was less variability in the relative risks after allowing for the methodological shortcomings.

CONCLUSIONS

Based on evidence from the most methodologically sound IBM studies, the most likely impact of European service mammography screening programmes was a breast cancer mortality reduction of 26% (95% confidence interval 13-36%) among women invited for screening and followed up for 6-11 years.

The impact of mammographic screening on breast cancer mortality in Europe: a review of observational studies

OBJECTIVES

To assess the impact of population-based mammographic screening on breast cancer mortality in Europe, considering different methodologies and limitations of the data.

METHODS

We conducted a systematic literature review of European trend studies (n = 17), incidence-based mortality (IBM) studies (n = 20) and case-control (CC) studies (n = 8). Estimates of the reduction in breast cancer mortality for women invited versus not invited and/or for women screened versus not screened were obtained. The results of IBM studies and CC studies were each pooled using a random effects meta-analysis.

RESULTS

Twelve of the 17 trend studies quantified the impact of population-based screening on breast cancer mortality. The estimated breast cancer mortality reductions ranged from 1% to 9% per year in studies reporting an annual percentage change, and from 28% to 36% in those comparing post- and prescreening periods. In the IBM studies, the pooled mortality reduction was 25% (relative risk [RR] 0.75, 95% confidence interval [CI] 0.69-0.81) among invited women and 38% (RR 0.62, 95% CI 0.56-0.69) among those actually screened. The corresponding pooled estimates from the CC studies were 31% (odds ratio [OR] 0.69, 95% CI 0.57-0.83), and 48% (OR 0.52, 95% CI 0.42-0.65) adjusted for self-selection.

CONCLUSIONS

Valid observational designs are those where sufficient longitudinal individual data are available, directly linking a woman's screening history to her cause of death. From such studies, the best 'European' estimate of breast cancer mortality reduction is 25-31% for women invited for screening, and 38-48% for women actually screened. Much of the current controversy on breast cancer screening is due to the use of inappropriate methodological approaches that are unable to capture the true effect of mammographic screening.

European guidelines for quality assurance in colorectal cancer screening and diagnosis: overview and introduction to the full supplement publication

Population-based screening for early detection and treatment of colorectal cancer (CRC) and precursor lesions, using evidence-based methods, can be effective in populations with a significant burden of the disease provided the services are of high quality. Multidisciplinary, evidence-based guidelines for quality assurance in CRC screening and diagnosis have been developed by experts in a project co-financed by the European Union. The 450-page guidelines were published in book format by the European Commission in 2010.  They include 10 chapters and over 250 recommendations, individually graded according to the strength of the recommendation and the supporting evidence. Adoption of the recommendations can improve and maintain the quality and effectiveness of an entire screening process, including identification and invitation of the target population, diagnosis and management of the disease and appropriate surveillance in people with detected lesions. To make the principles, recommendations and standards in the guidelines known to a wider professional and scientific community and to facilitate their use in the scientific literature, the original content is presented in journal format in an open-access Supplement of Endoscopy. The editors have prepared the present overview to inform readers of the comprehensive scope and content of the guidelines.

Cost effectiveness of human papillomavirus test of cure after treatment for cervical intraepithelial neoplasia in England: economic analysis from NHS Sentinel Sites Study

OBJECTIVES

To evaluate the cost effectiveness of human papillomavirus testing after treatment for cervical intraepithelial neoplasia (CIN).

DESIGN

Economic analysis using a Markov modelling approach to combine cost and epidemiological data from the NHS Sentinel Sites Study with data from previous studies of post-treatment recurrence rates.

SETTING

English NHS Cervical Cancer Screening Programme.

INTERVENTIONS

Management guidelines after treatment of CIN involving annual cytology follow-up for 10 years, compared with alternative protocols using the human papillomavirus test to reduce the amount of post-treatment surveillance.

MAIN OUTCOME MEASURES

Cases of underlying CIN3+ averted at 10 years and costs per 1000 women treated.

RESULTS

Model predictions indicated that, at observed levels of compliance with post-treatment recommendations, management with only cytological follow-up would result in 29 residual cases of recurrent CIN3+ by 10 years and would cost £358,222 (€440,426; $574,910) (discounted) per 1000 women treated. Implementation of human papillomavirus test of cure in cytologically negative women according to the sentinel sites protocol would avert an additional 8.4 cases of CIN 3+ and reduce costs by £9388 per 1000 women treated.

CONCLUSIONS

Human papillomavirus test of cure would be more effective and would be cost saving compared with cytology only follow-up. The results of this evaluation support the full scale implementation of human papillomavirus test of cure after treatment of CIN within the NHS Cervical Screening Programme.

European guidelines for quality assurance in colorectal cancer screening and diagnosis. First Edition--Evaluation and interpretation of screening outcomes

Multidisciplinary, evidence-based guidelines for quality assurance in colorectal cancer screening and diagnosis have been developed by experts in a project coordinated by the International Agency for Research on Cancer. The full guideline document covers the entire process of population-based screening. It consists of 10 chapters and over 250 recommendations, graded according to the strength of the recommendation and the supporting evidence. The 450-page guidelines and the extensive evidence base have been published by the European Commission. The chapter on evaluation and interpretation of screening outcomes includes 20 graded recommendations. The content of the chapter is presented here to promote international discussion and collaboration by making the principles and standards recommended in the new EU Guidelines known to a wider professional and scientific community. Following these recommendations has the potential to enhance the control of colorectal cancer through improvement in the quality and effectiveness of the screening process, including multi-disciplinary diagnosis and management of the disease.

Disease will limit future food supply from the global crustacean fishery and aquaculture sectors

Seafood is a highly traded food commodity. Farmed and captured crustaceans contribute a significant proportion with annual production exceeding 10 M metric tonnes with first sale value of $40bn. The sector is dominated by farmed tropical marine shrimp, the fastest growing sector of the global aquaculture industry. It is significant in supporting rural livelihoods and alleviating poverty in producing nations within Asia and Latin America while forming an increasing contribution to aquatic food supply in more developed countries. Nations with marine borders often also support important marine fisheries for crustaceans that are regionally traded as live animals and commodity products. A general separation of net producing and net consuming nations for crustacean seafood has created a truly globalised food industry. Projections for increasing global demand for seafood in the face of level or declining fisheries requires continued expansion and intensification of aquaculture while ensuring best utilisation of captured stocks. Furthermore, continued pressure from consuming nations to ensure safe products for human consumption are being augmented by additional legislative requirements for animals (and their products) to be of low disease status. As a consequence, increasing emphasis is being placed on enforcement of regulations and better governance of the sector; currently this is a challenge in light of a fragmented industry and less stringent regulations associated with animal disease within producer nations. Current estimates predict that up to 40% of tropical shrimp production (>$3bn) is lost annually, mainly due to viral pathogens for which standard preventative measures (e.g. such as vaccination) are not feasible. In light of this problem, new approaches are urgently required to enhance yield by improving broodstock and larval sourcing, promoting best management practices by farmer outreach and supporting cutting-edge research that aims to harness the natural abilities of invertebrates to mitigate assault from pathogens (e.g. the use of RNA interference therapeutics). In terms of fisheries losses associated with disease, key issues are centred on mortality and quality degradation in the post-capture phase, largely due to poor grading and handling by fishers and the industry chain. Occurrence of disease in wild crustaceans is also widely reported, with some indications that climatic changes may be increasing susceptibility to important pathogens (e.g. the parasite Hematodinium). However, despite improvements in field and laboratory diagnostics, defining population-level effects of disease in these fisheries remains elusive. Coordination of disease specialists with fisheries scientists will be required to understand current and future impacts of existing and emergent diseases on wild stocks. Overall, the increasing demand for crustacean seafood in light of these issues signals a clear warning for the future sustainability of this global industry. The linking together of global experts in the culture, capture and trading of crustaceans with pathologists, epidemiologists, ecologists, therapeutics specialists and policy makers in the field of food security will allow these issues to be better identified and addressed.

Screening women aged 40-49 years

Recent recommendations have reignited the debate about mammographic screening in women below age 50 years. Evidence from randomised controlled trials and results from service screening in some countries show a benefit of screening women below age 50 with a screening interval of up to two years. The benefit of such screening in terms of mortality reduction will be lower than that in older women, whilst potential harms include false positive screens and resulting anxiety, risk of overdiagnosis and possible radiation risk. The balance of benefits to possible harms, and the perception of this balance will vary both according to individual priorities and risk. Minimising harms and identifying those women who will benefit most from screening should remain a priority.

Measuring interobserver variation in a pathology EQA scheme using weighted κ for multiple readers

Background

A Urological Pathology External Quality Assurance (EQA) Scheme in the UK has reported observer variation in the diagnosis and grading of adenocarcinoma in prostatic biopsies using basic κ statistics, which rate all disagreements equally.

Aim

The aim of this study is to use customised weighting schemes to report κ statistics that reflect the closeness of interobserver agreement in the prostate EQA scheme.

Methods

A total of 83, 114 and 116 pathologists took part, respectively, in three web-based circulations and were classified as either expert or other readers. For analyses of diagnosis, there were 10, 8 and 8 cases in the three circulations, respectively. For analyses of Gleason Sum Score, only invasive cases were included, leaving 5, 5 and 6 cases, respectively. Analyses were conducted using customised weighting schemes with ‘pairwise-weighted’ κ for multiple readers.

Results

Analysis of diagnosis for all circulations and all readers gave a composite κ value of 0.86 and pairwise-weighted κ (κp–w) value of 0.91, both regarded as ‘almost perfect’ agreement. This was due to the high proportion of responses that showed partial agreement. Analysis of Gleason Sum Score gave κ=0.38 and κp–w=0.58 over all circulations and all readers, indicating that discrepancies occur at the boundary between adjacent grades and may not be as clinically significant as suggested by composite κ.

Conclusion

Weighted κ show higher levels of agreement than previously reported as they have the advantage of applying weighting, which reflects the relative importance of different types of discordance in diagnosis or grading. Agreement on grading remained low.

Carriage of methicillin-resistant Staphylococcus aureus by veterinarians in Australia

OBJECTIVE

To estimate the prevalence of carriage of methicillin-resistant Staphylococcus aureus (MRSA) among Australian veterinarians.

METHODS

Individuals attending veterinary conferences in Australia in 2009 were recruited to provide nasal swabs and complete a questionnaire about their professional activities. Swabs were processed by standard methods for detecting MRSA and questionnaire responses were used to group veterinarians according to their areas of major work emphasis (species and practice type). Prevalence was estimated for each of these grouping and contingency tables and regression tree analysis used to explain the variation in MRSA carriage.

RESULTS

Among the 771 respondents 'industry and government veterinarians' (controls) had the lowest prevalence of MRSA carriage at 0.9%. Veterinarians with horses as a major area of work emphasis had a prevalence of 11.8% (13-fold that of controls) and those whose only major emphasis was horses had a prevalence of 21.4% (23-fold that of controls). Veterinarians with dogs and cats as a major activity had a 4.9% prevalence (5-fold that of controls). Prevalence rates for other major activities (pigs, dairy and beef cattle, avian and wildlife) were also increased, but were estimated from smaller numbers of respondents. Regression tree analysis clearly isolated equine veterinarians and dog and cat practitioners as groups at increased risk of carriage of MRSA.

CONCLUSION

Carriage of MRSA is a notable occupational health issue for veterinarians in clinical practice in Australia, particularly those who work with horses.

MAVARIC - a comparison of automation-assisted and manual cervical screening: a randomised controlled trial

OBJECTIVES

The principal objective was to compare automation-assisted reading of cervical cytology with manual reading using the histological end point of cervical intraepithelial neoplasia grade II (CIN2) or worse (CIN2+). Secondary objectives included (i) an assessment of the slide ranking facility of the Becton Dickinson (BD) FocalPoint™ Slide Profiler (Becton Dickinson, Franklin Lakes, NJ, USA), especially 'No Further Review', (ii) a comparison of the two approved automated systems, the ThinPrep® Imaging System (Hologic, Bedford, MA, USA) and the BD FocalPoint Guided Screener Imaging System, and (iii) automated versus manual in terms of productivity and cost-effectiveness.

DESIGN

A 1 : 2 randomised allocation of slides to either manual reading or automation-assisted paired with manual reading. Cytoscreeners were blinded to whether samples would be read only manually or manually paired with automated. Slide reading procedures followed real-life laboratory protocol to produce a final result and, for paired readings, the worse result determined the management. Costs per event were estimated and combined with productivity to produce a cost per slide, per woman and per CIN2+ and cervical intraepithelial neoplasia grade III (CIN3) or worse (CIN3+) lesion detected. Cost-effectiveness was estimated using cost per CIN2+ detected. Lifetime cost-effectiveness in terms of life-years and quality-adjusted life-years was estimated using a mathematical model.

SETTING

Liquid-based cytology samples were obtained in primary care, and a small number of abnormal samples were obtained from local colposcopy clinics, from different women, in order to enrich the proportion of abnormals. All of the samples were read in a single large service laboratory. Liquid residues used for human papillomavirus (HPV) triage were tested (with Hybrid Capture 2, Qiagen, Crawley, UK) in a specialist virology laboratory in Edinburgh, UK. Histopathology was read by a specialist gynaecological pathology team blinded to HPV results and type of reading.

PARTICIPANTS

Samples were obtained from women aged 25-64 years undergoing primary cervical screening in Greater Manchester, UK, with small proportions from women outside this age range and from women undergoing colposcopy.

INTERVENTIONS

The principal intervention was automation-assisted reading of cervical cytology slides which was paired with a manual reading of the same slide. Low-grade cytological abnormalities (borderline and mild dyskaryosis) were triaged with HPV testing to direct colposcopy referral. Women with high-grade cytology were referred for colposcopy and those with negative cytology were returned to recall.

MAIN OUTCOME MEASURES

The principal outcome measure was the sensitivity of automation-assisted reading relative to manual for the detection of CIN2+. A secondary outcome measure was cost-effectiveness of each type of reading to detect CIN2+. The study was powered to detect a relative sensitivity difference equivalent to an absolute difference of 5%.

RESULTS

The principal finding was that automated reading was 8% less sensitive relative to manual, 6.3% in absolute terms. 'No further review' was very reliable and, if restricted to routine screening samples, < 1% of CIN2+ would have been missed. Automated and manual were very similar in terms of cost-effectiveness despite a 60%-80% increase in productivity for automation-assisted reading.

CONCLUSIONS

The significantly reduced sensitivity of automated reading, combined with uncertainty over cost-effectiveness, suggests no justification at present to recommend its introduction. The reliability of 'no further review' warrants further consideration as a means of saving staff time.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN66377374.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 15, No. 3. See the HTA programme website for further project information.

A practical application of analysing weighted kappa for panels of experts and EQA schemes in pathology

Background

Kappa statistics are frequently used to analyse observer agreement for panels of experts and External Quality Assurance (EQA) schemes and generally treat all disagreements as total disagreement. However, the differences between ordered categories may not be of equal importance (eg, the difference between grades 1 vs 2 compared with 1 vs 3). Weighted kappa can be used to adjust for this when comparing a small number of readers, but this has not as yet been applied to the large number of readers typical of a national EQA scheme.

Aim

To develop and validate a method for applying weighted kappa to a large number of readers within the context of a real dataset: the UK National Urological Pathology EQA Scheme for prostatic biopsies.

Methods

Data on Gleason grade recorded by 19 expert readers were extracted from the fixed text responses of 20 cancer cases from four circulations of the EQA scheme. Composite kappa, currently used to compute an unweighted kappa for large numbers of readers, was compared with the mean kappa for all pairwise combinations of readers. Weighted kappa generalised for multiple readers was compared with the newly developed ‘pairwise-weighted’ kappa.

Results

For unweighted analyses, the median increase from composite to pairwise kappa was 0.006 (range −0.005 to +0.052). The difference between the pairwise-weighted kappa and generalised weighted kappa for multiple readers never exceeded ±0.01.

Conclusion

Pairwise-weighted kappa is a suitable and highly accurate approximation to weighted kappa for multiple readers.

Automation-assisted versus manual reading of cervical cytology (MAVARIC): a randomised controlled trial

BACKGROUND

The standard for reading cervical cytology is for a cytoscreener to manually search across an entire slide for abnormal cells using a conventional microscope. Automated technology can select fields of view to assess abnormal cells, which allows targeted reading by cytoscreeners. In the Manual Assessment Versus Automated Reading In Cytology (MAVARIC) trial, we compared the accuracy of these techniques for the detection of underlying disease.

METHODS

For this randomised controlled trial, women aged 25-64 years undergoing primary cervical screening in Manchester, UK, were randomly assigned (1:2) to receive either manual reading only or paired reading (automation-assisted reading and manual reading), between March 1, 2006, and Feb 28, 2009. In the paired arm, two automated systems were used-the ThinPrep Imaging System and the FocalPoint GS Imaging System. General practices and community clinics were randomised to either ThinPrep or to SurePath (for the FocalPoint system) liquid-based cytology with block randomisation stratified by deprivation index. Samples were then individually randomised to manual reading only or paired reading only. Laboratory staff were unaware of the allocation of each slide and concealment was maintained until the end of the reporting process. The primary outcome was sensitivity of automation-assisted reading relative to manual reading for the detection of underlying cervical intraepithelial neoplasia grade 2 or worse (CIN2+) in the paired arm. This trial is registered, number ISRCTN66377374.

FINDINGS

73,266 liquid-based cytology samples were obtained from women undergoing primary cervical screening; 24,688 allocated to the manual-only arm and 48,578 to the paired-reading arm. Automation-assisted reading was 8% less sensitive than manual reading (relative sensitivity 0·92, 95% CI 0·89-0·95), which was equivalent to an absolute reduction in sensitivity of 6·3%, assuming the sensitivity of manual reading to be 79%. Specificity of automation-assisted reading relative to manual reading increased by 0·6% (1·006, 95% CI 1·005-1·007).

INTERPRETATION

The inferior sensitivity of automation-assisted reading for the detection of CIN2+, combined with an inconsequential increase in specificity, suggests that automation-assisted reading cannot be recommended for primary cervical screening.

Design issues in cancer screening trials

Randomised controlled trials avoid many of the potential biases associated with the evaluation of cancer screening. Nevertheless there are many issues concerning the design of such trials that require careful consideration and that will influence interpretation of the results. This article discusses issues related to recruitment and randomisation, which will affect the extent to which the population studied, is representative of the eventual target population of a screening programme. It addresses sample size considerations, the use of appropriate outcome measures and the timing of the intervention. Finally, issues related to ensuring appropriate analyses are discussed.

Assessing the amount of unscheduled screening ("contamination") in the control arm of the UK "Age" Trial

The UK Age Trial of mammographic screening from age 40 has reported a nonsignificant 17% reduction in breast cancer mortality calculated on an "intention to treat" basis. High levels of ad hoc screening in the control arm could potentially have diluted the estimated effect.

OBJECTIVES

To estimate the level of unscheduled mammography in the control arm of the UK Age Trial.

METHODS

Data were obtained from questionnaires sent to a random sample of 3,706 women at five centers in the control arm of this trial. Questions included in the Office for National Statistics Omnibus Surveys about the timing of and reasons for any breast screening provided comparable data. The overall response rate was 58.8%.

RESULTS

Overall, 24.9% (95% confidence interval, 23.0-26.8) of Age Trial controls responding reported ever having had a mammogram, 18.2% reported a mammogram for symptomatic reasons, and 8.4% reported unscheduled mammography. Overall, 4.0% and 1.8% of women reported symptomatic and unscheduled mammography, respectively, within the previous 12 months. Results from the Omnibus surveys were similar, 14.2% of women reported previous mammography for symptomatic reasons or follow-up after breast cancer and 6.8% reported unscheduled mammography.

CONCLUSIONS

The level of contamination due to mammographic screening in the control arm of the Age Trial was low and will have had a minimal effect on the estimated reduction in mortality from breast cancer.

IMPACT

Estimating the extent of screening in the control arm in randomized trials of screening is important to inform interpretation of the results.

Effects of a prostate awareness pilot on GP consultations and PSA requests

BACKGROUND

A Department of Health prostate awareness initiative, piloted in Coventry in 2006, promoted reporting of symptoms of benign prostatic hyperplasia, prostatitis and prostate cancer to GPs without causing sudden increases in workload. Qualitative evaluation showed a wide distribution of materials.

OBJECTIVES

Evaluation of effects of the pilot on rates of GP urological consultations, prescriptions and prostate-specific antigen (PSA) requests in general practice in Coventry and three control areas.

METHODS

Data on GP consultations provided by the General Practice Research Database for three to five practices per area covered the periods 1 October 2005 to 31 March 2006 and 1 October 2006 to 31 March 2007. Pathology laboratory data on PSA requests covered 18 months from 1 December 2005 in consenting practices: 44/55 (80%) in Coventry and 102/159 (64%) in control areas. The rates of GP consultations for urological symptoms and of prescriptions issued for urological conditions per 100 person-years in men with no prior diagnosis of benign or malignant prostate disease and rates of PSA tests per 100 men were analysed.

RESULTS

There was no significant change in consultation rates for urological symptoms over time in Coventry. The rate of prescriptions and of PSA testing increased in Coventry before the pilot began (P < 0.001) but there was no sudden increase after the pilot launch with similar trends in the control areas.

CONCLUSIONS

There was no increase in GP workload following the start of the pilot. Routine data can be used in evaluation but should be linked to surveys of awareness, health-seeking behaviour and delivery of campaign materials.

Test sensitivity in the European prostate cancer screening trial: results from Finland, Sweden, and the Netherlands

Test sensitivity pertains to the ability of a test to identify subjects with the target disorder. In cancer screening, test sensitivity can be estimated using interval cancer incidence as an indicator of false-negative result. A randomized trial provides the optimal approach for estimating test sensitivity, as the control arm provides the expected rates. We estimated the sensitivity of the prostate-specific antigen test using incidence method, i.e., based on incidence of interval cancer among subjects with negative screening results, compared with that in the control arm. Data from three centers in the European randomized screening trial were used to estimate interval cancer incidence (I(I)) among 39,389 men with negative screening tests. This was compared with incidence among the 79,525 men in the control arm of the trial (I(c)) to estimate test sensitivity (S = 1 - I(I) / I(C)). Confidence intervals were calculated using simulations, assuming that the number of cases follows a Poisson distribution. The estimated test sensitivity following the first screen was 0.87 (0.83-0.92) in Finland, 0.87 (0.62-1.00) in Sweden, and 0.93 (95% confidence interval, 0.90-0.96) in the Netherlands. There was some indication of a higher test sensitivity for aggressive cancers (0.85-0.98 for non-organ-confined cases or Gleason 8-10) and for the second screening round (approximately 0.85-0.95). Test sensitivity varied to some extent between the three centers in the European trial, probably reflecting variation in screening protocols, but was acceptable in the first screening round, and may be better for aggressive cancers and in the second screening round.

Population screening for colorectal cancer: the implications of an ageing population

Population screening for colorectal cancer (CRC) has recently commenced in the United Kingdom supported by the evidence of a number of randomised trials and pilot studies. Certain factors are known to influence screening cost-effectiveness (e.g. compliance), but it remains unclear whether an ageing population (i.e. demographic change) might also have an effect. The aim of this study was to simulate a population-based screening setting using a Markov model and assess the effect of increasing life expectancy on CRC screening cost-effectiveness. A Markov model was constructed that aimed, using a cohort simulation, to estimate the cost-effectiveness of CRC screening in an England and Wales population for two timescales: 2003 (early cohort) and 2033 (late cohort). Four model outcomes were calculated; screened and non-screened cohorts in 2003 and 2033. The screened cohort of men and women aged 60 years were offered biennial unhydrated faecal occult blood testing until the age of 69 years. Life expectancy was assumed to increase by 2.5 years per decade. There were 407 552 fewer people entering the model in the 2033 model due to a lower birth cohort, and population screening saw 30 345 fewer CRC-related deaths over the 50 years of the model. Screening the 2033 cohort cost £96 million with cost savings of £43 million in terms of detection and treatment and £28 million in palliative care costs. After 30 years of follow-up, the cost per life year saved was £1544. An identical screening programme in an early cohort (2003) saw a cost per life year saved of £1651. Population screening for CRC is costly but enables cost savings in certain areas and a considerable reduction in mortality from CRC. This Markov simulation suggests that the cost-effectiveness of population screening for CRC in the United Kingdom may actually be improved by rising life expectancies.

The effect of mammographic screening and hormone replacement therapy use on breast cancer incidence in England and Wales

DESIGN

An extended age-period-cohort model was used to estimate the effect of mammographic screening and hormone replacement therapy on breast cancer incidence in England and Wales between 1971 and 2001.

RESULTS

Incidence of breast cancer increased noticeably in women attending screening for the first time compared with nonattenders [rate ratio (RR), 1.73; 95% confidence interval (95% CI), 1.67-1.80]. Incidence was also 18% to 35% higher in attenders relative to nonattenders in subsequent screening rounds. In the first 3 years after women left the screening program, rates of breast cancer were reduced (RR, 0.88; 95% CI, 0.86-0.90), but by 7 to 9 years after screening, the rates had returned to the expected level (RR, 0.97; 95% CI, 0.94-1.00). The estimated RR of hormone replacement therapy on breast cancer incidence was 1.55 (95% CI, 1.37-1.75). Screening is estimated to increase a woman's lifetime risk of being diagnosed with breast cancer from 7.8% to 8.6%.

CONCLUSIONS

It is estimated that in the absence of screening, rates of breast cancer incidence would have continued to increase. A study at the individual subject level would be beneficial to assess the level of overdiagnosis associated with breast cancer screening.

Prevalence of type-specific HPV infection by age and grade of cervical cytology: data from the ARTISTIC trial

Human papillomavirus (HPV) infection causes cervical cancer and premalignant dysplasia. Type-specific HPV prevalence data provide a basis for assessing the impact of HPV vaccination programmes on cervical cytology. We report high-risk HPV (HR-HPV) type-specific prevalence data in relation to cervical cytology for 24 510 women (age range: 20–64; mean age 40.2 years) recruited into the ARTISTIC trial, which is being conducted within the routine NHS Cervical Screening Programme in Greater Manchester. The most common HR-HPV types were HPV16, 18, 31, 51 and 52, which accounted for 60% of all HR-HPV types detected. There was a marked decline in the prevalence of HR-HPV infection with age, but the proportion due to each HPV type did not vary greatly with age. Multiple infections were common below the age of 30 years but less so between age 30 and 64 years. Catch-up vaccination of this sexually active cohort would be expected to reduce the number of women with moderate or worse cytology by 45%, but the number with borderline or mild cytology would fall by only 7%, giving an overall reduction of 12% in the number of women with abnormal cytology and 27% in the number with any HR-HPV infection. In the absence of broader cross-protection, the large majority of low-grade and many high-grade abnormalities may still occur in sexually active vaccinated women.

The contribution of APTIMA Combo 2 assay to the diagnosis of gonorrhoea in genitourinary medicine setting

For 929 female and 821 male patients attending a genitourinary clinic, samples intended for chlamydia diagnosis were dual tested by nucleic acid amplification for both chlamydia and Neisseria gonorrhoeae (NG). The assay used, Gen-probe APTIMA Combo 2 (AC2) detected all cases of NG found by conventional microscopy and culture. AC2 identified additional patients who had partners with NG, but were themselves negative by microscopy and culture. Few, if any, false-positive AC2 results were found. Use of AC2 increased the number of patients treated for NG. It can reduce the number of specimens required and may limit the need for multiple site testing.

The UK colorectal cancer screening pilot: results of the second round of screening in England

An evaluation of the second round of faecal occult blood (FOB) screening in the English site of the UK Colorectal Cancer Screening Pilot (comprising the Bowel Cancer Screening Pilot based in Rugby, general practices in four Primary Care Trusts, and their associated hospitals) was carried out. A total of 127 746 men and women aged 50–69 and registered in participating general practices were invited to participate. In all, 15.9% were new invitees not included in the previous round. A total of 52.1% of invitees returned a screening kit. Uptake varied with gender, age, and level of deprivation; was lower than in the first round (51.9 vs 58.5% P<0.0001), but was high (81.1%) in those who had participated in the first round with a negative result. Test positivity was 1.77%, significantly higher than in the first round, and the detection rate of neoplasia similar (5.67 per 1000), resulting in a lower positive predictive value. The sensitivity of FOBt in the first round was estimated as 57.7–64.4%. There was a significant impact on workload, particularly on endoscopy services. The cancer detection rate (0.94 per 1000) was lower than in the first round. Effort will be required to minimise inequalities in uptake, and to ensure adequate capacity of endoscopy services.

Pseudocowpox Virus: The Etiological Agent of Contagious Ecthyma (Auzdyk) in Camels (Camelus dromedarius) in the Arabian Peninsula

We have determined the nucleotide sequence of DNA extracted from pustules, saliva, and blood of camels presenting with contagious ecthyma, in Bahrain and also from a sample (SACamel) of infected tissue from a camel that had presented with contagious ecthyma in 1998 in Saudi Arabia (1). Sequence homologies and phylogenetic analysis showed that this extracted DNA was more closely related to Pseudocowpox virus (PCPV) than Orf virus (ORFV), which infects sheep, goats, and other animal species. The phylogeny also demonstrated that PCPV in Arabian camels was phylogenetically distinct from, and circulates independently of, ruminant-associated PCPV from Europe.

Radiological and pathological findings of interval cancers in a multi-centre, randomized, controlled trial of mammographic screening in women from age 40-41 years

AIM

The aim of this study was to analyse the radiographic findings of the screening mammograms of women with interval cancer who participated in a multi-centre, randomized, controlled trial of mammographic screening in women from age 40-48 years.

MATERIALS AND METHODS

The screening and diagnostic mammograms of 208 women with interval cancers were reviewed. Abnormalities were classified as malignant, subtle and non-specific.

RESULTS

Eighty-seven (42%) of women had true, 66 (32%) occult and 55 (26%) false-negative interval cancers. The features most frequently missed or misinterpreted were granular microcalcification (38%), asymmetric density (27%) and distortion (22%). Thirty-seven percent of abnormal previous screens were classified as malignant, 39% subtle change and 21% as non-specific. Granular calcifications were significantly more common on the diagnostic mammograms of false-negative interval cancers than those of true interval cancers (28 versus 14%, p=0.04). Occult interval cancers were more likely to be <10 mm and <15 mm in invasive pathological size than other interval cancers (p=0.03 and 0.005, respectively). True interval cancers were more likely to be histologically grade 3 than other interval cancers (p=0.04). Women who developed true and false-negative interval cancers had similar background patterns, but women with occult cancers had a higher proportion of dense patterns (p<0.05).

CONCLUSION

Interval cancers in a young screening population have a high proportion of occult lesions that are small and occur in dense background patterns. The proportion of interval cancers that are false negative is similar that seen in older populations and granular microcalcification is the commonest missed mammographic feature.

Radiological findings of screen-detected cancers in a multi-centre randomized, controlled trial of mammographic screening in women from age 40 to 48 years

AIM

To elucidate the mammographic findings of screen-detected cancers in women screened between 40-48 years, and to establish the frequency and nature of abnormal findings on previous mammograms in women with screen-detected cancers.

METHODS

A radiology review panel consisting of three experienced breast radiologists viewed the screening mammograms in chronological order, confirming that any abnormalities detected corresponded to the cancers detected at later screens. An analysis correlating mammographic features with median invasive size and the proportion measuring less than 10 and 15mm was performed.

RESULTS

Two hundred and thirty-two women had screen-detected invasive cancers with mammograms available for review. The most frequent features seen at diagnosis were spiculate mass, ill-defined mass, granular calcification, deformity and comedo calcification. Thirty-four percent of mammograms showed calcification. The mammographic sign associated with smallest median size was calcification. Calcification was also the mammographic abnormality most frequently associated with cancers <10mm in size. In total there were 147 abnormal previous screens of 87 women. The most commonly missed features were granular microcalcification, deformity and ill-defined mass. Of the missed abnormalities 20% were classified as malignant, 43% as subtle change and 32% as non-specific.

CONCLUSION

Compared with older women, screen-detected cancer in younger women more commonly manifests as calcification and less frequently a spiculate mass. Calcification is the sign most frequently associated with invasive cancers <10mm in size. Calcification and deformity are the signs most frequently seen on the previous mammograms of women with screen-detected cancer.

A model of the natural history of screen-detected prostate cancer, and the effect of radical treatment on overall survival

The lead time and over-detection associated with prostate-specific antigen (PSA) screening, and generational improvements in all-cause mortality, make prostate cancer outcome studies from the pre-PSA era difficult to interpret in a contemporary setting. We developed a competing-risks hazard model to estimate the natural history of screen-detected prostate cancer, and the impact of radical treatment on overall survival. The model of hazard of mortality was fitted to clinical outcome data from the pre-PSA era, and the effects of screening, generational mortality improvements and radical treatment were incorporated. Sensitivities to the choice of baseline data and values of key parameters were assessed. Lead-time estimates in men diagnosed aged 55-59 years were 14.1, 9.3 and 5.0 years for men with Gleason scores <7, 7 and >7, respectively, assuming biennial screening with 100% attendance. Central estimates of 15-year prostate cancer mortality for conservative management of screen-detected prostate cancer ranged from 0 to 2% for Gleason scores <7, 9 to 31% for Gleason score 7 and 28-72% for Gleason scores >7. For men aged 55-59 years at diagnosis, the predicted absolute 15-year survival benefit from curative treatment was 0, 12 and 26% for men with Gleason scores <7, 7 and >7, respectively. Estimates of the survival benefit of radical treatment were relatively insensitive to values of key parameters. The case for curative treatment, rather than conservative management, of screen-detected localised prostate cancer is strongest in men with high-grade disease. This conclusion contrasts with current patterns of care.

A UK-based investigation of inter- and intra-observer reproducibility of Gleason grading of prostatic biopsies

AIMS

The frequency of prostatic core biopsies to detect cancer has been increasing with more widespread prostate specific antigen (PSA) testing. Gleason score has important implications for patient management but morphological reproducibility data for British practice are limited. Using literature-based criteria nine uropathologists took part in a reproducibility study.

METHODS

Each of the nine participants submitted slides from consecutive cases of biopsy-diagnosed cancer assigned to the Gleason score groups 2-4, 5-6, 7 and 8-10 in the original report. A random selection of slides was taken within each group and examined by all pathologists, who were blind to the original score. Over six circulations, new slides were mixed with previously read slides, resulting in a total of 47 of 81 slides being read more than once.

RESULTS

For the first readings of the 81 slides, the agreement with the consensus score was 78% and overall interobserver agreement was kappa 0.54 for Gleason score groups 2-4, 5-6, 7, 8-10. Kappa values for each category were 0.33, 0.56, 0.44 and 0.68, respectively. For the 47 slides read more than once, intra-observer agreement was 77%, kappa 0.66. The study identified problems in core biopsy interpretation of Gleason score at levels 2-4 and 7. Patterns illustrated by Gleason as 2 tended to be categorized as 3 because of the variable acinar size and unassessable lesional margin. In slides with consensus Gleason score 7, 13% of readings were scored 6 and in slides with consensus 6, 18% of readings were scored 7.

CONCLUSIONS

Recommendations include the need to increase objectivity of the Gleason criteria but limits of descriptive morphology may have to be accepted.

Detection rates of high-grade prostate cancer during subsequent screening visits. Results of the European Randomized Screening Study for Prostate Cancer

Screening for prostate cancer using prostate-specific antigen (PSA) tests has led to a stage and grade shift as compared to the pre-PSA era. Effectiveness of screening for prostate cancer should be manifested by a reduction in detection rate of aggressive cancers during subsequent screening. In 6 centers of the European Randomized Screening study for Prostate Cancer, a total of 58,710 men were tested for prostate cancer. Screening centers differed with regard to age-range, screening interval and biopsy indications. During the 2nd visit, the proportion of Gleason score 6 cancers increased from 62.5 to 75%, mainly at the expense of Gleason score 7 cancers. High-grade (Gleason score 8-10) cancer detection rates varied per screening center during the 1st visit from 5.1 to 41.1, and during the 2nd visit from 6.4 to 29.3/10,000 men. The overall detection rate of high-grade cancers showed a reduction during the 2nd visit from 26 to 12/10,000 men, an effect mainly attributable to the screening center with the highest cancer detection rate (i.e. 507/10,000 men). Variations in detection rates among screening centers related among others to biopsy compliance and age range.

A study of Gleason score interpretation in different groups of UK pathologists; techniques for improving reproducibility

AIMS

To test the effectiveness of a teaching resource (a decision tree with diagnostic criteria based on published literature) in improving the proficiency of Gleason grading of prostatic cancer by general pathologists.

METHODS

A decision tree with diagnostic criteria was developed by a panel of urological pathologists during a reproducibility study. Twenty-four general histopathologists tested this teaching resource. Twenty slides were selected to include a range of Gleason score groups 2-4, 5-6, 7 and 8-10. Interobserver agreement was studied before and after a presentation of the decision tree and criteria. The results were compared with those of the panel of urological pathologists.

RESULTS

Before the teaching session, 83% of readings agreed within +/- 1 of the panel's consensus scores. Interobserver agreement was low (kappa = 0.33) compared with that for the panel (kappa = 0.62). After the presentation, 90% of readings agreed within +/- 1 of the panel's consensus scores and interobserver agreement amongst the pathologists increased to kappa = 0.41. Most improvement in agreement was seen for the Gleason score group 5-6.

CONCLUSIONS

The lower level of agreement among general pathologists highlights the need to improve observer reproducibility. Improvement associated with a single training session is likely to be limited. Additional strategies include external quality assurance and second opinion within cancer networks.

The feasibility and results of a population-based approach to evaluating prostate-specific antigen screening for prostate cancer in men with a raised familial risk

The feasibility of a population-based evaluation of screening for prostate cancer in men with a raised familial risk was investigated by studying reasons for non-participation and uptake rates according to postal recruitment and clinic contact. The levels of prostate-specific antigen (PSA) and the positive predictive values (PPV) for cancer in men referred with a raised PSA and in those biopsied were analysed. First-degree male relatives (FDRs) were identified through index cases (ICs): patients living in two regions of England and diagnosed with prostate cancer at age ⩽65 years from 1998 to 2004. First-degree relatives were eligible if they were aged 45–69 years, living in the UK and had no prior diagnosis of prostate cancer. Postal recruitment was low (45 of 1687 ICs agreed to their FDR being contacted: 2.7%) but this was partly due to ICs not having eligible FDRs. A third of ICs in clinic had eligible FDRs and 49% (192 out of 389) agreed to their FDR(s) being contacted. Of 220 eligible FDRs who initially consented, 170 (77.3%) had a new PSA test taken and 32 (14.5%) provided a previous PSA result. Among the 170 PSA tests, 10% (17) were ⩾4 ng ml⁻¹ and 13.5% (23) tests above the age-related cutoffs. In 21 men referred, five were diagnosed with prostate cancer (PPV 24%; 95% CI 8, 47). To study further the effects of screening, patients with a raised familial risk should be counselled in clinic about screening of relatives and data routinely recorded so that the effects of screening on high-risk groups can be studied.

Impact of a national external quality assessment scheme for breast pathology in the UK

BACKGROUND

This article presents the results and observed effects of the UK National Health Service Breast Screening Programme (NHSBSP) external quality assurance scheme in breast histopathology.

AIMS/METHODS

The major objectives were to monitor and improve the consistency of diagnoses made by pathologists and the quality of prognostic information in pathology reports. The scheme is based on a twice yearly circulation of 12 cases to over 600 registered participants. The level of agreement was generally measured using kappa statistics.

RESULTS

Four main situations were encountered with respect to diagnostic consistency, namely: (1) where consistency is naturally very high-this included diagnosing in situ and invasive carcinomas (and certain distinctive subtypes) and uncomplicated benign lesions; (2) where the level of consistency was low but could be improved by making guidelines more detailed and explicit-this included histological grading; (3) where consistency could be improved but only by changing the system of classification-this included classification of ductal carcinoma in situ; and (4) where no improvement in consistency could be achieved-this included diagnosing atypical hyperplasia and reporting vascular invasion. Size measurements were more consistent for invasive than in situ carcinomas. Even in cases where there is a high level of agreement on tumour size, a few widely outlying measurements were encountered, for which no explanation is readily forthcoming.

CONCLUSIONS

These results broadly confirm the robustness of the systems of breast disease diagnosis and classification adopted by the NHSBSP, and also identify areas where improvement or new approaches are required.

The NHS breast screening programme (pathology) EQA: experience in recent years relating to issues involved in individual performance appraisal

BACKGROUND

The original role of the National Health Service breast screening programme (pathology) external quality assessment (EQA) scheme was educational; it aimed to raise standards, reinforce use of common terminology, and assess the consistency of pathology reporting of breast disease in the UK.

AIMS/METHODS

To examine the performance (scores) of pathologists participating in the scheme in recent years. The scheme has evolved to help identify poor performers, reliant upon setting an acceptable cutpoint. Therefore, the effects of different cutpoint strategies were evaluated and implications discussed.

RESULTS/CONCLUSIONS

Pathologists who joined the scheme improved over time, particularly those who did less well initially. There was no obvious association between performance and the number of breast cancer cases reported each year. This is not unexpected because the EQA does not measure expertise, but was established to demonstrate a common level of performance (conformity to consensus) for routine cases, rather than the ability to diagnose unusual/difficult cases. A new method of establishing cutpoints using interquartile ranges is proposed. The findings also suggest that EQA can alter a pathologist's practice: those who leave the scheme (for whatever reason) have, on average, marginally lower scores. Consequently, with the cutpoint methodology currently used (which is common to several EQA schemes) there is the potential for the cutpoint to drift upwards. In future, individuals previously deemed competent could subsequently be erroneously labelled as poor performers. Due consideration should be given to this issue with future development of schemes.

Feasibility of familial PSA screening: psychosocial issues and screening adherence

This study examined factors that predict psychological morbidity and screening adherence in first-degree relatives (FDRs) taking part in a familial PSA screening study. Prostate cancer patients (index cases - ICs) who gave consent for their FDRs to be contacted for a familial PSA screening study to contact their FDRs were also asked permission to invite these FDRs into a linked psychosocial study. Participants were assessed on measures of psychological morbidity (including the General Health Questionnaire; Cancer Worry Scale; Health Anxiety Questionnaire; Impact of Events Scale); and perceived benefits and barriers, knowledge; perceived risk/susceptibility; family history; and socio-demographics. Of 255 ICs, 155 (61%) consented to their FDRs being contacted. Of 207 FDRs approached, 128 (62%) consented and completed questionnaires. Multivariate logistic regression revealed that health anxiety, perceived risk and subjective stress predicted higher cancer worry (P = 0.05). Measures of psychological morbidity did not predict screening adherence. Only past screening behaviour reliably predicted adherence to familial screening (P = 0.05). First-degree relatives entering the linked familial PSA screening programme do not, in general, have high levels of psychological morbidity. However, a small number of men exhibited psychological distress.

Lifetime effects, costs, and cost effectiveness of testing for human papillomavirus to manage low grade cytological abnormalities: results of the NHS pilot studies

OBJECTIVES

To predict the incremental lifetime effects, costs, and cost effectiveness of using human papillomavirus testing to triage women with borderline or mildly dyskaryotic cervical smear results for immediate colposcopy.

DESIGN

Modelling study.

SETTING

Three centres participating in NHS pilot studies, United Kingdom. Population Women aged 25-64 with borderline or mildly dyskaryotic cervical smear results.

INTERVENTIONS

Screening using conventional cytology, liquid based cytology, and four strategies with different age cut-off points and follow up times that used combined liquid based cytology and human papillomavirus testing (adjunctive human papillomavirus testing).

RESULTS

The model predicts that compared with using conventional cytology without testing for human papillomavirus, testing for the virus in conjunction with liquid based cytology for women with borderline or mildly dyskaryotic cervical smear results (aged 35 or more) would cost 3735 pounds sterling (5528 euros; 6474 dollars) per life year saved. Extending adjunctive human papillomavirus testing in combination with liquid based cytology to include women aged between 25 and 34 costs an additional 4233 pounds sterling per life year saved. Human papillomavirus testing is likely to reduce lifetime repeat smears by 52%-86% but increase lifetime colposcopies by 64%-138%.

CONCLUSIONS

Testing for human papillomavirus to manage all women with borderline or mildly dyskaryotic cervical smear results is likely to be cost effective. The predicted increase in lifetime colposcopies, however, deserves careful consideration.

Effect of testing for human papillomavirus as a triage during screening for cervical cancer: observational before and after study

OBJECTIVE

To assess the effect of introducing testing for human papillomavirus combined with liquid based cytology in women with low grade cytological abnormalities.

DESIGN

Observational before and after study.

SETTING

Three cervical screening laboratories, England.

PARTICIPANTS

5654 women aged 20-64 with low grade cytological abnormalities found at routine cervical screening in a pilot; 5254 similar women in the period before the pilot.

INTERVENTIONS

Human papillomavirus testing combined with liquid based cytology in the management of women with borderline or mildly dyskaryotic cervical smear results compared with conventional smear tests, with immediate referral to colposcopy of women positive for human papillomavirus.

RESULTS

57.9% (3187/5506) of women tested in the pilot were positive for human papillomavirus. The rate of repeat smears fell by 74%, but the rate of referral to colposcopy for low grade cytological abnormalities more than doubled. The estimated negative predictive value of human papillomavirus testing varied between 93.8% and 99.7%.

CONCLUSION

The addition of testing for human papillomavirus in women with low grade cytological abnormalities resulted in a reduction in the rate of repeat smears, but an increase in rates of referral to colposcopy.

The development of a quality assurance programme for HPV testing within the UK NHS cervical screening LBC/HPV studies

BACKGROUND

Cervical screening by cytology is effective but lacks sensitivity. The addition of human papillomavirus (HPV) testing can improve the effectiveness of screening for early identification of cervical disease. As HPV testing represents a new technology, a quality assurance (QA) programme is necessary to confirm the accuracy of results.

OBJECTIVE

Our main objective was to design a QA programme for use in the English NHS liquid-based cytology (LBC) and HPV Cervical Screening Pilot Study. Our second objective was to use the knowledge gained to design a QA scheme for future general use within cervical screening and HPV testing programmes.

STUDY DESIGN

Four elements were included in the programme: provision of clinical samples of known HPV status for internal quality control (IQC), distribution of panels of unknown samples for external quality assessment (EQA), resubmission of aliquots of samples to the reference laboratory for repeat testing and resubmission to reference laboratory to check for transport problems. Three sites took part in the QA programme using PreservCyt medium and ThinPrep for LBC preparation. The assay used at test sites was HPV hybrid capture (hc2) while the quality assurance laboratory used a combination of hc2, in-house HPV polymerase chain reaction (PCR) tests and HPV linear array (LA).

RESULTS

Four negative, three low positive and 11 positive pools were used in 22 distributions of IQC samples. Seven distributions each of five 'unknown' EQA samples were sent out. Over 400 samples underwent repeat testing. Discrepant samples were further assessed to provide an explanation. Inter- and intra-laboratory consistency was high as measured by Kappa statistics and 96% agreement for EQA samples was obtained.

CONCLUSIONS

The validity of the QA programme was established and reproducibility in different lab settings was reassuring. These results support the use of hc2 as a potential screening test in diagnostic laboratories. The need for robust quality assurance of HPV testing in cervical screening programmes was confirmed and lessons learnt from this pilot study will be incorporated in future schemes.

Overdiagnosis and overtreatment of breast cancer: overdiagnosis in randomised controlled trials of breast cancer screening

Data from randomised controlled trials of mammographic screening can be used to determine the extent of any overdiagnosis, as soon as either a time equivalent to the lead-time has elapsed after the final screen, or the control arm has been offered screening. This paper reviews those randomised trials for which breast cancer incidence data are available. In recent trials in which the control group has not been offered screening, an excess incidence of breast cancer remains after many years of follow-up. In those trials in which the control arm has been offered screening, although there is a possible shift from invasive to in situ disease, there is no evidence of overdiagnosis as a result of incident screens.

Factors influencing the radiative surface temperature of grey seal (Halichoerus grypus) pups during early and late lactation

The aim of this study was to examine the variation in body surface temperature of grey seal (Halichoerus grypus) pups throughout lactation in response to different environmental conditions. Radiative surface temperatures (T (r), degrees C) of pups were measured on the Isle of May (56 degrees 11'N, 02 degrees 33'W), southeast Scotland from 29 October to 25 November 2003. Records were obtained from a total of 60 pups (32 female and 28 male) from three different pupping sites during early and late lactation. Pups were sheltered from high wind speeds but air temperature, humidity and solar radiation at pupping sites were similar to general meteorological conditions. The mean T (r) of all pups was 15.8 degrees C (range 7.7-29.7 degrees C) at an average air temperature of 10.2 degrees C (range 6.5-13.8 degrees C). There was no difference in the mean T (r) of pups between early and late lactation. However, the T (r) varied between different regions of the body with hind flippers on average 2-6 degrees C warmer than all other areas measured. There was no difference in mean T (r) of male and female pups and pup body mass did not account for the variation in T (r) during early or late lactation. Throughout the day there was an increase in the T (r) of pups and this explained 20-28% of the variation in T (r) depending on stage of lactation. There was no difference in the mean T (r) of pups between pupping sites or associated with different substrate types. Wind speed and substrate temperature had no effect on the T (r) of pups. However, solar radiation, air temperature and relative humidity accounted for 48% of the variation in mean T (r) of pups during early lactation. During late lactation air temperature and solar radiation alone accounted for 43% of the variation in T (r). These results indicate that environmental conditions explain only some of the variation in T (r) of grey seal pups in natural conditions. Differences in T (r) however indicate that the cost of thermoregulation for pups will vary throughout lactation. Further studies examining intrinsic factors such as blubber thickness and activity levels are necessary before developing reliable biophysical models for grey seals.