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S M Moss

Publications and source records attributed to S M Moss.

At least 19 recordsLinked to original sources
PubMed2006

Cost-effectiveness of screening with contrast enhanced magnetic resonance imaging vs X-ray mammography of women at a high familial risk of breast cancer.

Contrast enhanced magnetic resonance imaging (CE MRI) is the most sensitive tool for screening women who are at high familial risk of breast cancer. Our aim in this study was to assess the cost-effectiveness of X-ray mammography (XRM), CE MRI or both strategies combined. In total, 649 women were enrolled in the MARIBS study and screened with both CE MRI and mammography resulting in 1881 screens and 1-7 individual annual screening events. Women aged 35-49 years at high risk of breast cancer, either because they have a strong family history of breast cancer or are tested carriers of a BRCA1, BRCA2 or TP53 mutation or are at a 50% risk of having inherited such a mutation, were recruited from 22 centres and offered annual MRI and XRM for between 2 and 7 years. Information on the number and type of further investigations was collected and specifically calculated unit costs were used to calculate the incremental cost per cancer detected. The numbers of cancer detected was 13 for mammography, 27 for CE MRI and 33 for mammography and CE MRI combined. In the subgroup of BRCA1 (BRCA2) mutation carriers or of women having a first degree relative with a mutation in BRCA1 (BRCA2) corresponding numbers were 3 (6), 12 (7) and 12 (11), respectively. For all women, the incremental cost per cancer detected with CE MRI and mammography combined was pound28 284 compared to mammography. When only BRCA1 or the BRCA2 groups were considered, this cost would be reduced to pound11 731 (CE MRI vs mammography) and pound15 302 (CE MRI and mammography vs mammography). Results were most sensitive to the unit cost estimate for a CE MRI screening test. Contrast-enhanced MRI might be a cost-effective screening modality for women at high risk, particularly for the BRCA1 and BRCA2 subgroups. Further work is needed to assess the impact of screening on mortality and health-related quality of life.

Adult↗
PubMed2006

Does the accuracy of single reading with CAD (computer-aided detection) compare with that of double reading?: A review of the literature.

AIM: To examine current evidence to determine whether the accuracy of single reading with computed-aided detection (CAD) compares with that of double reading. METHODS: We performed a literature review to identify studies where both protocols had been investigated and compared. We identified eight studies that compared single reading with CAD against double reading, of which six reported on comparisons of both sensitivity and specificity. RESULTS: Of the six studies identified, three showed no differences in either sensitivity or specificity. One showed single reading with CAD had a higher sensitivity at the same specificity, another that single reading with CAD had a higher specificity at the same sensitivity. However, one study, in a real-life setting, showed that single reading with CAD had a higher sensitivity but a lower specificity. CONCLUSION: As the majority of the studies were not in a real-life setting, used test sets, lacked sufficient training in the use of CAD and simulated double reading (using a protocol of recall if one suggests), current evidence is therefore limited as to the accuracy, in terms of sensitivity and specificity, of single reading with CAD in comparison with the most common practice in the UK of double reading using a protocol of consensus or arbitration.

Breast Neoplasms↗
PubMed2006

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

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

Adult↗
PubMed2006

The effect of data quality at the time of introduction of population-based screening on the estimate of programme impact using surrogate outcome measures.

OBJECTIVE: The aim of this study was to examine the availability and quality of surrogate outcome measure data to enable the evaluation of the breast screening programme. As the observed effect on mortality of a screening programme occurs many years after the introduction of screening, surrogate outcome measures offer an attractive alternative, allowing estimates of the effect to be calculated earlier. METHODS: The exercise was undertaken by the Oxford Cancer Intelligence Unit and the Cancer Screening Evaluation Unit in collaboration with cancer registries in England, Scotland and Wales. RESULTS: The conclusion of the exercise was that, in general, the available data quality was insufficient to allow a precise estimate of the overall mortality reduction from breast screening to be made using surrogate measures. CONCLUSIONS: When a screening programme is started, it is vital that forward planning is undertaken to ensure that the necessary information is ready to be collected before the start of the programme. The use of surrogate measures is dependent on high-quality data in the uninvited group of women (pre-screening or from a staggered start over areas), and improving data quality over time after the start of the programme is of very limited value for a surrogate measures approach. The collection of appropriate high-quality information before the programme starts is, therefore, critical to measuring the success of the programme. Cancer registries and staff within the screening programme need to be ready to collect the appropriate data before the introduction of a screening programme. The exercise undertaken therefore has important implications where new screening programmes are being considered.

Breast Neoplasms↗
PubMed2005

The effect of changing from one to two views at incident (subsequent) screens in the NHS breast screening programme in England: impact on cancer detection and recall rates.

AIM: To assess the effect on cancer detection and recall rates of changing from one to two views for incident (subsequent) screens. METHODS: Controlled, comparative, observational study of programmes in NHS breast screening programme in England. SUBJECTS: women aged 50-64 years were screened by the NHSBSP between 1 April 2001 and 31 March 2003. RESULTS: The effect of changing to two-view mammography was a 20% increase in overall incident screen cancer detection rate, with the biggest effect seen for small (<15 mm) invasive cancers. This increased detection rate was achieved with an 11% drop-in recall rate. CONCLUSION: The introduction of two-view mammography for incident screens has resulted in considerable improvements in overall NHS breast screening performance.

Aged↗
PubMed2005

Is radiologists' volume of mammography reading related to accuracy? A critical review of the literature.

The current UK quality assurance guidelines for radiologists in the NHS breast screening programme require those reporting screening mammograms to read a minimum of 5000 cases per year. We aimed to review the evidence for this and to assess whether there was justification for lowering the required level. A literature search was conducted to identify relevant studies where accuracy of reporting mammograms was related to reading volume. Three of the five studies reviewed suggested a positive association between reading volume and sensitivity, but there were few data on volumes above 5000 cases per year. The available evidence did not provide any basis for reducing the threshold volume. Further work is needed, in a UK or European setting, to study the relationship between reading volume and accuracy at higher volume levels and also the separate effects of reading volume and reading experience.

Breast Neoplasms↗
PubMed2004

Monitoring and evaluating the performance of the UK NHS Cervical Screening Programme: monitoring performance by using cytology outcomes adjusted for population characteristics.

Current quality assurance measures used in the NHS cervical screening programme (NHSCSP) include a review of laboratories with percentages of moderate/severe and borderline/mild smear results outside the 10th-90th percentiles. The method is limited by the fact that many of these outlier smear percentages may reflect laboratories covering populations with low or high risk and/or short or long average screening intervals. This paper outlines a new approach to aid the detection of outlier laboratories, by using data collected at the primary care trust (PCT) or health authority (HA) level and making allowances for population characteristics and screening interval. The setting is the NHSCSP in England using annual data provided by HAs. Data from the screening year 2000-01 is used to illustrate the methodology, although the methods can also be applied to data at the PCT level (now being collected for 2002-03 onwards). Percentages of smear results have been analysed against a series of explanatory variables using logistic regression models. These explanatory variables include Townsend deprivation index, uptake-corrected ethnic minority composition, a measure of screening interval, area type and region. An expected percentage of borderline/mild and moderate/severe smears is estimated from the models and an observed : predicted ratio (OPRmod/sev and OPRbord/mild) calculated. Low values are suggestive of relative undercalling and high values overcalling, after allowance for population characteristics. Analysis of data for 2000-01 showed that the OPRmod/sev for the 99 HAs varied from 0.68 to 1.44. Laboratories with low percentages of moderate/severe smears, but associated with PCTs or HAs with OPRmod/sev values closer to unity may not need to be investigated as their observed rates are consistent with predicted rates based on population characteristics. The method could also be directly applied to laboratories if further information on the population covered by each laboratory were routinely collected.

Female↗
PubMed2002

Does individual programme size affect screening performance? Results from the United Kingdom NHS breast screening programme.

OBJECTIVE: The size (number of women screened) of the 95 individual NHS breast screening programmes (NHSBSPs) varies by a factor of 10. This study investigates the impact of size on the performance of individual programmes. METHOD: Data were collated from the 95 United Kingdom screening programmes on the standard statistical returns for the past 5 years (1 April 1995-31 March 2000). Additional information was obtained from questionnaires. The number of women screened between 1 April 1999 and 31 March 2000 determined the size of a programme. The bottom 25% were defined as small, the middle 50% as medium, and the top 25% as large. On average large programmes screened about four times as many women as small programmes and medium programmes about twice as many. Performance was evaluated using cancer detection rates, referral rates for assessment, and positive predictive value (PPV) of assessment using PPV referral diagrams. RESULTS: The performance of smaller programmes was shown to be marginally poorer than medium and large sized programmes in that they detected fewer cancers and had a lower PPV. The smallest 25% of programmes had an invasive cancer detection rate 13% less than the medium and large programmes. However, if these programmes had an equivalent detection rate to the medium/large programmes the national detection rate would only increase by about 2%. This is because the 75% of programmes described as medium and large screen about 90% of all women. It is therefore important to place the clinical importance of these findings in context when considering any envisaged possible solutions. CONCLUSIONS: Although the performance of smaller programmes was shown to be poorer than that of the larger programmes, it is not clear from this study exactly why this is so. A likely contributory factor based on experience of evaluating the NHSBSP is that performance problems in larger programmes have been easier to detect by quality assurance staff. The size of the small programmes and the few screen detected cancers (and inherent statistical instability in detection rates) mean that problems are difficult to identify. As a consequence small programmes which are genuinely performing marginally below specific standards are likely to receive less attention than larger programmes, and even under close scrutiny the causes are less likely to be found.

Breast Neoplasms↗
PubMed2002

The UK national study of magnetic resonance imaging as a method of screening for breast cancer (MARIBS).

The UK national study of magnetic resonance imaging as a method of screening for breast cancer (MARIBS) is in progress. The study design, accrual to date, and related research projects are described. Revised accrual rates and expected recruitment are given. 15 cancers have been detected to date, from a total of 1236 screening measurements. This event rate and the tumour grades reported are compared with recent reports from other studies in women at high risk of breast cancer.

Adult↗
PubMed2001

Routine breast screening for women aged 65-69: results from evaluation of the demonstration sites.

Routine programme data and specially designed surveys from 3 demonstration sites were analysed to determine the implications of extending the NHS Breast Screening Programme (NHSBSP), to include routine invitations for women up to 69 years. All women aged 65-69 and registered with GPs in these areas received routine invitations for breast screening along with those aged 50-64. Overall uptake was 71% in women aged 65-69 compared with 78% in younger women, but was > or = 90% in both groups who had previously attended within 5 years. Recall rates were lower for older women, but with a higher positive predictive value for cancer. The percentages of invasive cancer in different prognostic categories were similar in the 2 age groups. Older women took no longer to screen than younger women. The costs per woman invited or per woman screened were also similar to those for women aged 50-64, whilst the cost per cancer detected was some 34% lower in older women. Breast screening is as cost effective for women aged 65-69 as for those aged 50-64, with a higher cancer detection rate balancing shorter life expectancy. The proposed extension to the national programme will have considerable workforce implications for the NHSBSP and require additional resources.

Aged↗
PubMed2001

Pilot trial of interleukin-2 with granulocyte colony-stimulating factor for the mobilization of progenitor cells in advanced breast cancer patients undergoing high-dose chemotherapy: expansion of immune effectors within the stem-cell graft and post-stem-cell infusion.

PURPOSE: To evaluate whether administration of interleukin-2 (IL-2) with granulocyte colony-stimulating factor (G-CSF) improves mobilization of immune effector cells into the stem-cell graft of patients undergoing high-dose chemotherapy and autografting. PATIENTS AND METHODS: We performed a trial of stem-cell mobilization with IL-2 and G-CSF in advanced breast cancer patients receiving high-dose chemotherapy with cyclophosphamide, thiotepa, and carboplatin and stem cells followed by IL-2. The trial defined immune, hematologic, and clinical effects of IL-2 in this setting. RESULTS: Of 32 patients enrolled, nine received G-CSF alone for mobilization. Twenty-one of 23 patients mobilized with IL-2 plus G-CSF had stem cells collected with more mononuclear cells than those receiving G-CSF (19.3 v 10.4 x 10(8)/kg; P =.006), but fewer CD34(+) progenitor cells (6.9 v 22.0 x 10(6)/kg; P =.049). The IL-2 plus G-CSF-mobilized patients had greater numbers of activated T (CD3(+)/CD25(+)) cells (P =.009), natural killer (NK; CD56(+)) cells (P =.007), and activated NK (CD56 bright(+)) cells (P: =.039) than those patients mobilized with G-CSF. NK (P =.042) and lymphokine-activated killer (LAK) (P =.016) activity was increased in those mobilized with IL-2 + G-CSF, whereas G-CSF-mobilized patients had a decline in cytolytic activity. In the third week posttransplantation, immune reconstitution was superior in those mobilized with IL-2 plus G-CSF based on greater numbers of activated T cells (P =.003), activated NK cells (P =.04), and greater LAK activity (P =.003). The 16 of 21 IL-2 + G-CSF-mobilized patients with adequate numbers of stem cells (> 1.5 x 10(6) CD34(+) cells/kg) collected engrafted rapidly posttransplantation. CONCLUSION: The results demonstrate that G-CSF + IL-2 can enhance the number and function of antitumor effector cells in a mobilized autograft without impairing the hematologic engraftment, provided that CD34 cell counts are more than 1.5 x 10(6) cells/kg. Mobilization of CD34(+) stem cells does seem to be adversely affected. In those mobilized with IL-2 and G-CSF, post-stem-cell immune reconstitution of antitumor immune effector cells was enhanced.

Adult↗
PubMed2001

Reasons for variation in coverage in the NHS cervical screening programme.

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

Adult↗
PubMed2001

Monitoring and evaluating the UK National Health Service Breast Screening Programme: evaluating the variation in radiological performance between individual programmes using PPV-referral diagrams.

A high quality breast cancer screening programme can be defined as one offering both a high cancer detection rate and a low referral rate of women for further investigation. Such a programme will have as few women as possible undergoing further investigations who do not have a final diagnosis of breast cancer--that is, a high positive predictive value of referral for further investigation. This paper introduces a graphical technique to illustrate individual programme performance. The graph plots positive predictive value of referral against referral rate, with the cancer detection rate expressed as "isobars" on the graph. Confidence limits can be expressed as "boxes" on the diagram. The graph not only illustrates programme performance but also enables suggestions to be made to improve performance. The definition of high quality screening is seen to have a subjective element as well as an objective element, as radiologists have to balance screening sensitivity with specificity. The technique is illustrated using data from the individual screening programmes in the UK National Health Service Breast Screening Programme for the screening year 1 April 1998 to 31 March 1999. The methodology could also be applied to other national screening programmes.

Breast Neoplasms↗
PubMed2000

Lung cancer screening: improved survival but no reduction in deaths--the role of "overdiagnosis".

BACKGROUND: Randomized controlled trials (RCTs) of lung cancer screening consistently show an excess number of cancer cases and longer survival in screened groups, but no difference in mortality between screened and control populations. METHODS: The current study reviewed the various types of biases that confuse comparisons based on intermediate endpoints such as stage distribution and survival and the reasons for basing evaluations in RCTs of screening for early cancers on mortality from a specific cancer. RESULTS: Four RCTs all showed improved stage of disease and survival in screened subjects, but there was no difference in mortality between screened and unscreened populations. The possible explanations for the higher incidence are chance (failed randomization) or "overdiagnosis" (detection of cases by screening that otherwise would never have surfaced). Analysis of the trial results confirmed that chance alone was a very unlikely explanation. Evidence suggests that some overdiagnosis of lung cancer is likely in screened subjects. This is a consistent observation in all other programs of screening for early cancers (breast, prostate, and neuroblastoma). CONCLUSIONS: Overdiagnosis of cancer cases resulting from the screening process itself will give rise to excess cases of disease, and may, at least in part, explain the observations in the randomized trials.

Bias↗
PubMed2000

Effect of NHS breast screening programme on mortality from breast cancer in England and Wales, 1990-8: comparison of observed with predicted mortality.

OBJECTIVE: To assess the impact of the NHS breast screening programme on mortality from breast cancer in women aged 55-69 years over the period 1990-8. DESIGN: Age cohort model with data for 1971-89 used to predict mortality for 1990-8 with assumption of no major effect from screening or improvements in treatment until after 1989. Effect of screening and other factors on mortality estimated by comparing three year moving averages of observed mortality with those predicted (by five year age groups from 50-54 to 75-79), the effect of screening being restricted to certain age groups. SETTING: England and Wales. SUBJECTS: Women aged 40 to 79 years. RESULTS: Compared with predicted mortality in the absence of screening or other effects the total reduction in mortality from breast cancer in 1998 in women aged 55-69 was estimated as 21.3%. Direct effect of screening was estimated as 6.4% (range of estimates from 5.4-11.8%). Effect of all other factors (improved treatment with tamoxifen and chemotherapy, and earlier presentation outside the screening programme) was estimated as 14.9% (range 12.2-14.9%). CONCLUSIONS: By 1998 both screening and other factors, including improvements in treatment, had resulted in substantial reductions in mortality from breast cancer. Many deaths in the 1990s will be of women diagnosed in the 1980s and early 1990s, before invitation to screening. Further major effects from screening and treatment are expected, which together with cohort effects should result in further substantial reductions in mortality from breast cancer, particularly for women aged 55-69, over the next 10 years.

Adult↗
PubMed2000

Magnetic resonance imaging screening in women at genetic risk of breast cancer: imaging and analysis protocol for the UK multicentre study. UK MRI Breast Screening Study Advisory Group.

The imaging and analysis protocol of the UK multicentre study of magnetic resonance imaging (MRI) as a method of screening for breast cancer in women at genetic risk is described. The study will compare the sensitivity and specificity of contrast-enhanced MRI with two-view x-ray mammography. Approximately 500 women below the age of 50 at high genetic risk of breast cancer will be recruited per year for three years, with annual MRI and x-ray mammography continuing for up to 5 years. A symptomatic cohort will be measured in the first year to ensure consistent reporting between centres. The MRI examination comprises a high-sensitivity three-dimensional contrast-enhanced assessment, followed by a high-specificity contrast-enhanced study in equivocal cases. Multiparametric analysis will encompass morphological assessment, the kinetics of contrast agent uptake and determination of quantitative pharmacokinetic parameters. Retrospective analysis will identify the most specific indicators of malignancy. Sensitivity and specificity, together with diagnostic performance, diagnostic impact and therapeutic impact will be assessed with reference to pathology, follow-up and changes in diagnostic certainty and therapeutic decisions. Mammography, lesion localisation, pathology and cytology will be performed in accordance with the UK NHS Breast Screening Programme quality assurance standards. Similar standards of quality assurance will be applied for MR measurements and evaluation.

Adult↗