The impact of mammography screening programmes on incidence of advanced breast cancer in Europe: a literature review.

BACKGROUND: Observational studies have reported conflicting results on the impact of mammography service screening programmes on the advanced breast cancer rate (ABCR), a correlation that was firmly established in randomized controlled trials. We reviewed and summarized studies of the effect of service screening programmes in the European Union on ABCR and discussed their limitations. METHODS: The PubMed database was searched for English language studies published between 01-01-2000 and 01-06-2018. After inspection of titles and abstracts, 220 of the 8644 potentially eligible papers were considered relevant. Their abstracts were reviewed by groups of two authors using predefined criteria. Fifty studies were selected for full paper review, and 22 of these were eligible. A theoretical framework for their review was developed. Review was performed using a ten-point checklist of the methodological caveats in the analysis of studies of ABCR and a standardised assessment form designed to extract quantitative and qualitative information. RESULTS: Most of the evaluable studies support a reduction in ABCR following the introduction of screening. However, all studies were challenged by issues of design and analysis which could at least potentially cause bias, and showed considerable variation in the estimated effect. Problems were observed in duration of follow-up time, availability of reliable reference ABCR, definition of advanced stage, temporal variation in the proportion of unknown-stage cancers, and statistical approach. CONCLUSIONS: We conclude that much of the current controversy on the impact of service screening programmes on ABCR is due to observational data that were gathered and/or analysed with methodological approaches which could not capture stage effects in full. Future research on this important early indicator of screening effectiveness should focus on establishing consensus in the correct methodology.

FIT for the future: a case for risk-based colorectal cancer screening using the faecal immunochemical test.

Worldwide, the guaiac faecal occult blood test (gFOBT) is being replaced with the more accurate faecal immunochemical test (FIT) for colorectal cancer (CRC) screening. From January 2016, the National Screening Committee in the UK has recommended a change from the gFOBT to the FIT following a successful Bowel Cancer Screening Programme pilot study with over 40 000 participants. Although the test has shown improved uptake and the ability to detect significantly more colorectal cancers and advanced adenomas, the higher uptake and test positivity will challenge the capacity of colonoscopy services. One of the main advantages of the FIT is that it provides a quantitative haemoglobin concentration which has been shown to relate to the risk of CRC. Risk scoring systems which combine the FIT concentration with risk factor assessment have been shown to improve the sensitivity of the test. This individualized approach to screening could enable those at greatest risk to be referred for colonoscopy, optimizing resource use and ultimately patient outcomes.

Comparison of the performance of HPV tests in women with abnormal cytology: results of a study within the NHS cervical screening programme.

OBJECTIVE: The use of testing for human papillomavirus (HPV) is now recognized as an efficient means of triaging women with low-grade cytological abnormalities to either immediate referral to colposcopy or return to routine recall. We aimed to determine the sensitivity and specificity of each of four newer tests for HPV relative to the Qiagen Hybrid Capture 2 (HC2) assay in order to determine whether they could be approved for use in triage in the NHS cervical screening programme. METHODS: We compared the performance of each of four different HPV assays (Abbott M2000, Roche Cobas, Hologic Cervista and Gen-Probe APTIMA) with that of HC2 in order to determine the sensitivity and specificity of each test relative to HC2 for the detection of cervical intraepithelial neoplasia (CIN) grade 2 or worse, using routine cytology samples reported as borderline (atypical squamous cells) or mild dyskaryosis (low-grade squamous intraepithelial lesion) from six laboratories in England. All women who were found to be HPV positive on any test were referred to colposcopy. RESULTS: Between 2072 and 4217 tests were performed with each assay. All four assays were shown to have a relative sensitivity of no worse than 95% compared with HC2 when a cut-off of 2 relative light units (RLU) was used. All assays had higher relative specificity than HC2 for both borderline and mild cytology referrals (1.06-1.61). CONCLUSIONS: All assays tested met the criteria required. Consequently, all have now been approved for use in HPV triage in the NHS cervical screening programme.

Estimating breast cancer mortality reduction and overdiagnosis due to screening for different strategies in the United Kingdom.

BACKGROUND: The benefits and harms of population-wide mammography screening have been long debated. This study evaluated the impact of screening frequency and age range on breast cancer mortality reduction and overdiagnosis. METHODS: We developed a Markov simulation model for the evaluation of mammography screening in a cohort of British women born in 1935-40. RESULTS: For triennial screening in women aged 47-73, breast cancer mortality reduction and overdiagnosis was 18.1% (95% confidence interval: 17.3%, 19.0%) and 5.6% (5.1%, 6.1%), of all breast cancer deaths and diagnoses, respectively, from age 40 to 85 years. For annual screening in the same age range, estimates for both outcomes increased considerably to 35.0% (34.2%, 35.7%) and 7.6% (7.1%, 8.1%), respectively. For the age extension of triennial screening from 50-70 to 47-73, we estimated 5 (3, 7) incremental breast cancer deaths avoided and 14 (9, 19) incremental cases overdiagnosed per 10 000 women invited for screening. CONCLUSIONS: Estimates of mortality reduction and overdiagnosis were highly dependent on screening frequency, age range, and uptake, which may explain differences between some previous estimates obtained from randomised trials and from service screening.

Longer mean colonoscopy withdrawal time is associated with increased adenoma detection: evidence from the Bowel Cancer Screening Programme in England.

BACKGROUND AND STUDY AIMS: Increasing colonoscopy withdrawal time (CWT) is thought to be associated with increasing adenoma detection rate (ADR). Current English guidelines recommend a minimum CWT of 6 minutes. It is known that in the Bowel Cancer Screening Programme (BCSP) in England there is wide variation in CWT. The aim of this observational study was to examine the relationship between CWT and ADR. PATIENTS AND METHODS: The study examined data from 31 088 colonoscopies by 147 screening program colonoscopists. Colonoscopists were grouped in four levels of mean CWT ( < 7, 7 - 8.9, 9 - 10.9, and ≥ 11 minutes). Univariable and multivariable analysis (binary logistic and negative binomial regression) were used to explore the relationship between CWT, ADR, mean number of adenomas and number of right-sided and advanced adenomas. RESULTS: In colonoscopists with a mean CWT < 7 minutes, the mean ADR was 42.5 % compared with 47.1 % in the ≥ 11-minute group (P < 0.001). The mean number of adenomas detected per procedure increased from 0.77 to 0.94, respectively (P < 0.001). The increase in adenoma detection was mainly of subcentimeter or proximal adenomas; there was no increase in the detection of advanced adenomas. Regression models showed an increase in ADR from 43 % to 46.5 % for mean CWT times ranging from 6 to 10 minutes. CONCLUSIONS: This study demonstrates that longer mean withdrawal times are associated with increasing adenoma detection, mainly of small or right-sided adenomas. However, beyond 10 minutes the increase in ADR is minimal. Mean withdrawal times longer than 6 minutes are not associated with increased detection of advanced adenomas. Withdrawal time remains an important quality metric of colonoscopy.

Nottingham trial of faecal occult blood testing for colorectal cancer: a 20-year follow-up.

BACKGROUND: Three large randomised trials have shown that screening for colorectal cancer (CRC) using the faecal occult blood test (FOBt) can reduce the mortality from this disease. The largest of these trials, conducted in Nottingham since 1981, randomised 152,850 individuals between the ages of 45 and 74 years to an intervention arm receiving biennial Haemoccult (FOB) test kit or to a control arm. In 2006, the National Bowel Cancer Screening Programme was launched in England using the FOBt, with the expectation that it will reduce CRC mortality. AIMS: To compare the CRC mortality and incidence in the intervention arm with the control arm after long-term follow-up. METHODS: The 152,850 randomised individuals were followed up through local health records and central flagging (Office for National Statistics). RESULTS: At a median follow-up of 19.5 years there was a 13% reduction in CRC mortality (95% CI 3% to 22%) in the intervention arm despite an uptake at first invitation of approximately 57%. The CRC mortality reduction in those accepting the first screening test, adjusted for the rate of non-compliers, was 18%. There was no significant difference in mortality from causes other than CRC between the intervention and control arms. Despite removing 615 adenomas >10 mm in size from the intervention arm, there was no significant difference in CRC incidence between the two arms. CONCLUSIONS: Although the reduction in CRC mortality was sustained, further follow-up of the screened population has not shown a significant reduction in the CRC incidence. Moreover, despite the removal of many large adenomas there was no reduction in the incidence of invasive cancer which was independent of sex and site of the tumour.

Performance measures in three rounds of the English bowel cancer screening pilot.

OBJECTIVES: To compare performance measures across all three rounds of the English bowel cancer screening faecal occult blood test pilot and their relation to social deprivation and ethnicity. METHODS: In each round in three primary care trusts, data for a restricted population of over 48,500 aged 60-69 years were analysed. Individual-based data included postcode linked to area-based data on the Index of Multiple Deprivation (IMD) 2004, and ethnicity. Outcomes were the rates of screening and colonoscopy uptake, positivity and detection of neoplasia (adenomas or bowel cancer) and bowel cancer, and the positive predictive values (PPVs) of a positive test for neoplasia and bowel cancer. Sensitivity was calculated by the proportional incidence method using data on interval cancers identified from cancer registrations. RESULTS: The overall uptake rate was 61.8%, 57.0% and 58.7% in the first, second and third rounds, respectively. Although the PPV for cancer decreased over the course of the three rounds (10.9% in the 1st round, 6.5% in 3rd round), the PPV for all neoplasia remained relatively constant (42.6% in 1st round, 36.9% in 3rd round). Deprivation and non-white ethnic background (principally Indian subcontinent in the pilot region) were associated with low screening and colonoscopy uptake rates, and this changed little over the three screening rounds. Uptake was lower in men, although differences in uptake between men and women decreased over time. Non-participation in previous rounds was a strong predictor of low uptake. CONCLUSIONS: Performance measures are commensurate with expectations in a screening programme reaching its third round of screening, but a substantial ongoing effort is needed, particularly to address the effects of deprivation and ethnicity in relation to uptake.

Incidence of cervical intraepithelial neoplasia grade 2 or worse in colposcopy-negative/human papillomavirus-positive women with low-grade cytological abnormalities.

OBJECTIVE: To determine the risk of incident high-grade cervical intraepithelial neoplasia (CIN) in human papillomavirus (HPV) -positive women with low-grade cytological abnormalities who had a satisfactory normal colposcopy. DESIGN: A retrospective follow-up study within the NHS HPV/LBC pilot studies. SETTING: The NHS Cervical Screening Programme in England. POPULATION: A total of 1063 HPV-positive women with borderline or mild dyskaryosis who were negative at colposcopy from three sites within the NHS HPV/liquid-based cytology (LBC) pilot studies. METHODS: HPV triage took place in 2001/02. In 2009 all information on additional management on HPV-positive/colposcopy-negative women was requested. The rate of disease following a negative colposcopy was calculated, and survival analysis was used to determine whether the grade of referral cytology impacted on risk of subsequent disease. Results were compared with those in women from the same population who had not been HPV triaged. MAIN OUTCOME MEASURES: Incident CIN2 or worse during follow up. RESULTS: Of 1063 eligible women 965 had documented follow up. The cumulative rate of CIN2+ at 3 years in these women was 4.4% (95% CI 4.0-7.0%); the median time from normal colposcopy to final result was 27 months. There was no significant increase in the risk of future disease associated with age or initial cytology result. CONCLUSIONS: The rate of subsequent high-grade CIN among colposcopically negative triaged women was sufficiently low to justify return to routine recall.

An observational study to evaluate the performance of units using two radiographers to read screening mammograms.

AIM: To examine the performance of screening units in which a proportion of mammograms were double read using "non-discordant radiographer only (double) reading" (NDROR). MATERIALS AND METHODS: NDROR was used by seven pilot units between 2006 and 2009, and six further units in 2009 only. There were 51 comparison units. Screening performance outcome measures were calculated, and logistic regression was used to compare performance between the pilot and comparison units. RESULTS: Phase 1 pilot units read between on average 15 and 48% of mammograms per year using NDROR between 2006 and 2009 (median, 33%) and in 2009, phase 2 pilot units used NDROR to read between 4 and 77% of mammograms (median, 34%). The results showed an increase in recall rates in the phase 1 pilot units relative to the comparison units at both prevalent and incident screens (adjusted OR 1.09, 95% CI 1.05, 1.14; and adjusted OR 1.10, 95% CI 1.07, 1.14, respectively). There were also increases in the phase 2 pilot units relative to the comparison units; adjusted OR 1.08 (95% 1.00, 1.17) at prevalent screens, and adjusted OR 1.07 (95% CI 1.02, 1.14) at incident screens. There was no evidence to suggest a difference in cancer-detection rates between the pilot units and the comparison units. CONCLUSIONS: Evidence from the present study suggests that recall rates may increase as a result of units using radiographers to double read a proportion of their mammograms. However, there is little evidence to suggest that NDROR, as practiced by the pilot units in the present study, is likely to have major impacts on performance in the UK National Health Service Breast Screening Programme (NHSBSP), particularly if it is fully supported and closely monitored (particularly recall rates).

HPV testing as a triage for borderline or mild dyskaryosis on cervical cytology: results from the Sentinel Sites study.

BACKGROUND: Earlier pilot studies of human papillomavirus (HPV) triage concluded that HPV triage was feasible and cost-effective. The aim of the present study was to study the impact of wider rollout of HPV triage for women with low-grade cytology on colposcopy referral and outcomes. METHODS: Human papillomavirus testing of liquid-based cytology (LBC) samples showing low-grade abnormalities was used to select women for colposcopy referral at six sites in England. Samples from 10,051 women aged 25-64 years with routine call or recall cytology reported as borderline or mild dyskaryosis were included. RESULTS: Human papillomavirus-positive rates were 53.7% in women with borderline cytology and 83.9% in those with mild dyskaryosis. The range between sites was 34.8-73.3% for borderline cytology, and 73.4-91.6% for mild dyskaryosis. In the single site using both LBC technologies there was no difference in rates between the two technologies. The positive predictive value of an HPV test was 16.3% for CIN2 or worse and 6.1% for CIN3 or worse, although there was considerable variation between sites. CONCLUSION: Triaging women with borderline cytological abnormalities and mild dyskaryosis with HPV testing would allow approximately a third of these women to be returned immediately to routine recall, and for a substantial proportion to be referred for colposcopy without repeat cytology. Variation in HPV-positive rates results in differing colposcopy workload.

Interval cancers in the NHS breast cancer screening programme in England, Wales and Northern Ireland.

BACKGROUND: The United Kingdom NHS Breast Screening Programme was established in 1988, and women aged between 50 and 70 are routinely invited at three yearly intervals. Expected United Kingdom interval cancer rates have been calculated previously, but this is the first publication from an exercise to collate individual-based interval cancer data at a national level. METHODS: Interval cancer case ascertainment is achieved by the regular exchange of data between Regional Breast Screening Quality Assurance Reference Centres and Cancer Registries. The present analysis includes interval cancers identified in women screened between 1st April 1997 and 31st March 2003, who were aged between 50 and 64 at the time of their last routine screen. RESULTS: In the periods >0-<12 months, 12-<24 months and 24-<36 months after a negative screen, we found overall interval cancer rates and regional ranges of 0.55 (0.43-0.76), 1.13 (0.92-1.47) and 1.22 (0.93-1.57) per 1000 women screened, respectively. Rates in the period 33-<36 months showed a decline, possibly associated with early re-screening or delayed presentation. CONCLUSIONS: Interval cancer rates were higher than the expected rates in the 24-month period after a negative screen, but were similar to published results from other countries. Increases in background incidence may mean that the expected rates are underestimated. It is also possible that, as a result of incomplete case ascertainment, interval cancers rates were underestimated in some regions in which rates were less than the expected.

Increasingly strong reduction in breast cancer mortality due to screening.

BACKGROUND: Favourable outcomes of breast cancer screening trials in the 1970s and 1980s resulted in the launch of population-based service screening programmes in many Western countries. We investigated whether improvements in mammography and treatment modalities have had an influence on the effectiveness of breast cancer screening from 1975 to 2008. METHODS: In Nijmegen, the Netherlands, 55,529 women received an invitation for screening between 1975 and 2008. We designed a case-referent study to evaluate the impact of mammographic screening on breast cancer mortality over time from 1975 to 2008. A total number of 282 breast cancer deaths were identified, and 1410 referents aged 50-69 were sampled from the population invited for screening. We estimated the effectiveness by calculating the odds ratio (OR) indicating the breast cancer death rate for screened vs unscreened women. RESULTS: The breast cancer death rate in the screened group over the complete period was 35% lower than in the unscreened group (OR=0.65; 95% CI=0.49-0.87). Analysis by calendar year showed an increasing effectiveness from a 28% reduction in breast cancer mortality in the period 1975-1991 (OR=0.72; 95% CI=0.47-1.09) to 65% in the period 1992-2008 (OR=0.35; 95% CI=0.19-0.64). CONCLUSION: Our results show an increasingly strong reduction in breast cancer mortality over time because of mammographic screening.

Evaluation of extension of breast screening to women aged 65-70 in England using screening performance measures.

The objective of this study was to investigate screening performance measures in the English screening units that began inviting women aged 65-70 between 1 April 2001 and 1 April 2004. We analysed results after each unit commenced inviting women aged 65-70. In addition, we analysed data from units that invited this age group for a second time between 1 April 2004 and 31 March 2007. Results for women aged 65-70 were compared to women aged 50-64 and 60-64. Average uptake was 72.8% for women aged 65-70 and 76.7% for women aged 50-64. For women screened within the last 5 years, uptake was 88.7% for older women and 89.1% for younger women. For women previously screened within 5 years the invasive cancer detection rate was 17% higher in the 65-70 age group than in the 60-64 age group. The rates of recall to assessment and PPV were 3.5 and 27.6% in women aged 65-70 and 3.4 and 24.6% in women aged 50-64 respectively. These results suggest that, as in the earlier demonstration studies, uptake rates remain high in older women, and many more older women attend following an invitation than had previously self-referred. The cancer detection rate is higher in this older age group, whereas rates of recall are generally similar to those in younger women; consequently the PPV is also higher in older women.

Risk of cervical abnormality after age 50 in women with previously negative smears.

There is discussion over the benefit of continuing cervical screening in women over the age of 50 with a history of negative cytology. We aimed to determine the risk of abnormal cytology in such women. Screening history data from 1985 to 2003 were obtained for a cohort of 2 million women from the NHS cervical screening programme from four Health Authorities in England. The 57,651 women in the cohort who reached age 40 between 1 January 1985 and 31 December 1990 and had at least one routine or opportunistic smear between ages 50 and 54 were included in the analysis. Exposure groups (negative cytology history, negative but including inadequate smears, and positive history) were defined on the basis of screening histories from ages 40 to 49. Sixty-four percent (134/206) (95% CI: 57-71%) of the moderate dyskaryosis or worse lesions at ages over 50 were detected from women in the negative smear history group. After allowance for time since last negative smear, the relative risk for the first primary smear over the age of 50 having moderate dyskaryosis or worse decreased from 0.60 (95% CI: 0.41-0.84) for two negative smear episodes to 0.25 (95% CI: 0.10-0.56) for four negative smear episodes, compared with the positive history group. If screening were discontinued for all women over 50 with a negative history, the majority of cytological abnormalities now being detected at these ages that lead directly to referral to colposcopy would be missed.

Evaluation of bowel cancer registration data in England, 1996-2004.

BACKGROUND: The National Health Service (NHS) bowel cancer screening programme (BCSP) was initiated across England in April 2006. To determine the feasibility of using national cancer registration data to assess the impact of the BCSP on stage-specific incidence, we studied trends in the incidence rates of colon (ICD10 C18) and rectosigmoid junction and rectum (ICD10 C19-C20) cancers and the completeness of data on Dukes stage in England. METHODS: Data were obtained from all nine cancer registries for the period 1996-2004, before the introduction of the BCSP, in men and women aged 50-79 years. RESULTS: Overall, incidence rates declined by 1% per year in the 9 years before the introduction of the BCSP (P<0.001). Dukes stage was recorded for 60% of all registrations but this varied between regions and over time. Only four registries had completeness of 74% or more. Registrations with unknown Dukes stage decreased from 1996 to 2000, and then increased during 2001-2004 affecting trends in stage-specific incidence. CONCLUSION: To study the impact of the BCSP on stage-specific incidence, regional variations in data completeness need to be addressed.

The use of screening episodes linked to CIN3 and invasive cancer registrations to study outcomes from the NHS Cervical Screening Programme.

UNLABELLED: The use of screening episodes linked to CIN3 and invasive cancer registrations to study outcomes from the NHS Cervical Screening ProgrammeObjective: To examine how NHS cervical screening data can be collected and analysed in order to evaluate women's screening histories as episodes rather than as individual smears. DESIGN: Analysis of routine cervical screening data grouped into screening episodes for a cohort of women regarding episodes starting in a given year. SETTING: NHS Cervical Screening Programme. POPULATION: Data from four Health Authorities (now eight Primary Care Trusts) from the NHS Cervical Screening Programme with primary smears (first in an episode) taken between 1 April 1999 and 31 March 2000. METHODS: Cytology information obtained from the call/recall ('Exeter') computer system was linked to cervical intraepithelial neoplasia (CIN) 3 and invasive cancer outcome information obtained from cancer registries. Screening histories were divided into episodes, each starting with a primary smear that was followed up to episode closure or, for episodes still open followed for an average 4.25 years, from the primary smear. The episode was divided into two parts (up to referral to colposcopy and following the referral). The outcomes of the episodes are described including referral rate to colposcopy and CIN3 and invasive cancer rates by factors such as age. MAIN OUTCOME MEASURES: Episode histories and rates of referral to colposcopy, CIN3 and invasive cancer. RESULTS: There were 176 923 episodes from 176 319 women (1.003 episodes per woman) followed up to March 2004, the date at which the first phase of information accrual ceased. Of these episodes, 172 100 (97.3%) were closed either by a negative smear referring the woman back to routine recall or by default (defined as no smear recorded within 21 months following a smear requiring an action of repeat or refer to colposcopy). The remaining 4823 (2.7%) of episodes were still open, of which in 3121 (1.8%) the woman had been referred to colposcopy and in 1702 (1.0%) no referral decision had been made. Referral rates to colposcopy varied by age from 5.7% in women aged 20-24 years down to 0.9% in women aged 60-64 years. The overall efficiency of screening was highest for woman aged about 30 years, with a CIN3 detection rate of eight per 1000 women and a positive predictive value (for CIN3 or worse) of referral to colposcopy of 21%. CONCLUSION: The study has shown that routinely collected NHS cervical screening data can be combined to give information on complete episodes, allowing important performance measures to be studied. We suggest that in future information in the NHS screening system should be structured to facilitate such analysis and to allow cytology and histology information to be readily linked.

Coverage in the National Health Service Breast Screening Programme, 1996-2005: correcting for the first invitation of women between 50 and 52 years.

BACKGROUND: Coverage measures the ability of the National Health Service Breast Screening Programme (NHSBSP) to reach the eligible population and has a target of 70%. OBJECTIVE: To estimate coverage accurately for women aged 50-64. METHODS: Routine data from the KC63 return were used to calculate coverage for women aged 50-64 using an adjusted method that allows for the fact that women receive a first invitation to screening between 50 and 52.9 years. RESULTS: The adjusted average coverage between 1996 and 2005, for women aged 50-64 was 74.3% and the standard unadjusted average measure for the same period was 68.3%. Therefore, previous measures of coverage for this age group have underestimated coverage by approximately 9% and the adjusted figure is actually well above the target. CONCLUSION: In terms of coverage the programme has been performing better than previously reported. It is important to monitor the effect of an increasing workload on the programmes ability to re-invite women within three years of their last screen as maintaining coverage is an important factor in ensuring that the NHSBSP is effective in reducing mortality from breast cancer.

An examination of the role of opportunistic smear taking in the NHS cervical screening programme using data from the CSEU cervical screening cohort study.

OBJECTIVE: The objective of this study was to study the prevalence of opportunistic smear taking in the NHS cervical screening programme between 1999 and 2003 and the relationship of this to screening interval policy. DESIGN: A cohort study of nearly 2 million women, with data on screening at ages 20-64 years from 1988 to 2003 has been constructed. Data from 1999 to 2003 have been used in this analysis. Screening episodes have been divided into those where the primary smear was initiated by the national call/recall system (invitational), normally at 3- or 5-yearly intervals, and those initiated by the GP or woman (opportunistic). Opportunistic smears were further classified as routine (occurring within 6 months of 3 or 5 years) or sporadic (occurring at other times). SETTING: NHS cervical screening programme. POPULATION: Four Health Authorities in England (now Primary Care Trusts) with supplementary studies on national data. METHODS: Screening episodes have been defined. All episodes start with a primary smear defined as being invitational or opportunistic in origin. MAIN OUTCOME MEASURE: Proportion of primary smear that were invitational or opportunistic. RESULTS: In total, 72% of incident screen primary smears were invitational and 28% were opportunistic. The proportion of opportunistic primary smears was 17 and 43% in 3- or 5-yearly screening policy areas, respectively, resulting in a considerably reduced average screening interval for women aged 20-64 years in 5-year policy areas. CONCLUSION: The NHS cervical screening programme is strongly influenced by opportunistic smear taking. In particular, nominally 5-year policy areas experienced much higher levels of opportunistic smear taking than those with a 3-year policy, causing the average interval in the 5-year areas to be much shorter than the policy would suggest. In future, with the change in national policy for inviting women aged 25-49 years every 3 years and those aged 50-64 years every 5 years, the level of opportunistic smear taking, particularly in the older group of women, needs to be carefully monitored. A lack of compliance may result in greater than predicted costs with little or no additional cancer prevention.

Results from the UK NHS Breast Screening Programme 2000-05.

OBJECTIVE: To present results from the UK NHS breast screening programme (NHSBSP) for the six-year period from 1 April 1999 to 31 March 2005, and to compare these with targets. METHODS: Data are collected annually from all UK screening units on standard KC62 return forms. RESULTS: The prevalence of screen-positive cancer (cancer detection rate) has increased at both rounds during the six-year period. At the incident round, cancer detection rates increased by 24%, from 5.4 per 1000 in 2000 to 6.7 per 1000 in 2005 and the detection of small cancers (< or = 10 mm) has increased by 40%. Generally, quality measures in the programme continue to improve. However, while rates of recall at the incident screen decreased from 3.8% in 2000 to 3.6% in 2005, at the prevalent round, in 2005, 22% of units continued to recall more than 10% of women to assessment. CONCLUSIONS: The results suggest that the performance of the programme continues to improve. In the future, analysis of data on interval cancers will assist the interpretation of cancer detection rates.

Screening with magnetic resonance imaging and mammography of a UK population at high familial risk of breast cancer: a prospective multicentre cohort study (MARIBS).

BACKGROUND: Women genetically predisposed to breast cancer often develop the disease at a young age when dense breast tissue reduces the sensitivity of X-ray mammography. Our aim was, therefore, to compare contrast enhanced magnetic resonance imaging (CE MRI) with mammography for screening. METHODS: We did a prospective multicentre cohort study in 649 women aged 35-49 years with a strong family history of breast cancer or a high probability of a BRCA1, BRCA2, or TP53 mutation. We recruited participants from 22 centres in the UK, and offered the women annual screening with CE MRI and mammography for 2-7 years. FINDINGS: We diagnosed 35 cancers in the 649 women screened with both mammography and CE MRI (1881 screens): 19 by CE MRI only, six by mammography only, and eight by both, with two interval cases. Sensitivity was significantly higher for CE MRI (77%, 95% CI 60-90) than for mammography (40%, 24-58; p=0.01), and was 94% (81-99) when both methods were used. Specificity was 93% (92-95) for mammography, 81% (80-83) for CE MRI (p<0.0001), and 77% (75-79) with both methods. The difference between CE MRI and mammography sensitivities was particularly pronounced in BRCA1 carriers (13 cancers; 92%vs 23%, p=0.004). INTERPRETATION: Our findings indicate that CE MRI is more sensitive than mammography for cancer detection. Specificity for both procedures was acceptable. Despite a high proportion of grade 3 cancers, tumours were small and few women were node positive. Annual screening, combining CE MRI and mammography, would detect most tumours in this risk group.