Objective
Randomised controlled trials have shown a reduction in breast cancer mortality from mammography screening and it is the detection of high-grade invasive cancers that is responsible for much ...of this effect. We determined the detection rates of invasive cancers by grade, size and type of screen and estimated relative sensitivities with emphasis on grade 3 detection.
Methods
This observational study analysed data from over 11 million screening episodes (67,681 invasive cancers) from the English NHS breast screening programme over seven screening years 2009/2010 to 2015/2016 for women aged 45–70.
Results
At prevalent (first) screens (which are unaffected by screening interval), the detection rate of small (< 15 mm) invasive cancers was 0.95 per 1000 for grade 1, but for grade 3 only 0.30 per 1000. The ratio of small (< 15 mm) to large (≥ 15 mm) cancers was 1.8:1 for grade 1 but reversed to 0.5:1 for grade 3. We estimated that the relative sensitivity for grade 3 invasive cancers was 52% of that for grade 1 and the relative sensitivity for small (< 15 mm) grade 3 only 26% of that for small (< 15 mm) grade 1 invasive cancers.
Conclusions
Sensitivity for small grade 3 invasive cancers is poor compared with that for grade 1 and 2 invasive cancers and larger grade 3 malignancies. This observation is likely a limitation of the current technology related to the absence of identifiable mammographic features for small high-grade cancers. Future work should focus on technologies and strategies to improve detection of these clinically most significant cancers.
Key Points
• The detection of small high-grade invasive cancers is vital to reduce breast cancer mortality.
• We estimate the sensitivity for small grade 3 invasive cancers may be only 26% of that of small grade 1 invasive cancers. This is likely to be associated with the non-specific mammographic features for these cancers.
• New technologies and appropriate strategies using current technology are required to maximise the detection of small grade 3 invasive cancers.
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.
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.
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.
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.
Objective
To develop methods to model the relationship between cancer detection and recall rates to inform professional standards.
Methods
Annual screening programme information for each of the 80 ...English NHSBSP units (totalling 11.3 million screening tests) for the seven screening years from 1 April 2009 to 31 March 2016 and some Dutch screening programme information were used to produce linear and non-linear models. The non-linear models estimated the modelled maximum values (MMV) for cancers detected at different grades and estimated how rapidly the MMV was reached (the modelled ‘slope’ (MS)). Main outcomes include the detection rate for combined invasive/micro-invasive and high-grade DCIS (IHG) detection rate and the low/intermediate grade DCIS (LIG) detection rate.
Results
At prevalent screens for IHG cancers, 99% of the MMV was reached at a recall rate of 7.0%. The LIG detection rate had no discernible plateau, increasing linearly at a rate of 0.12 per 1000 for every 1% increase in recall rate. At incident screens, 99% of the MMV for IHG cancer detection was 4.0%. LIG DCIS increased linearly at a rate of 0.18 per 1000 per 1% increase in recall rate.
Conclusions
Our models demonstrate the diminishing returns associated with increasing recall rates. The screening programme in England could use the models to set recall rate ranges, and other countries could explore similar methodology.
Key Points
• Question: How can we determine optimum recall rates in breast cancer screening?
• Findings: In this large observational study, we show that increases in recall rates above defined levels are almost exclusively associated with false positive recalls and a very small increase in low/intermediate grade DCIS.
• Meaning: High recall rates are not associated with increases in detection of life-threatening cancers. The models developed in this paper can be used to help set recall rate ranges that maximise benefit and minimise harm.
To examine the association between recall, needle biopsy, and cancer detection rates to inform the setting of target ranges to optimise the benefit to harm ratio of breast screening programmes.
...Annual screening programme information from 2009/10 to 2015/16 for the 80 screening units of the English National Health Service Breast Screening Programme (totalling 11.3 million screening tests) was obtained from annual (KC62) returns. Linear regression models were used to examine the association between needle biopsy rates and recall rates and non-linear regression models to examine the association between cancer detection rates and needle biopsy rates.
The models show and quantify the diminishing returns for prevalent screens with increasing biopsy rates. A biopsy rate increase from 10 to 20 per 1,000 increases the cancer detection rate by 2.13 per 1,000 with four extra biopsies per extra cancer detected. Increasing the biopsy rate from 40 to 50 per 1,000, increases the cancer detection rate by only 0.25 per 1,000, with 40 extra biopsies per extra cancer detected. Although diminishing returns are also seen at incident screens, screening is generally more efficient.
Increasing needle biopsy rates leads to rapidly diminishing returns in cancer detection and a marked increase in non-malignant/benign needle biopsies. Much of the harms associated with screening in terms of false-positive recall rates and non-cancer biopsies occur at prevalent screens with much lower rates at incident screens. Needle biopsy rate targets should be considered together with recall rate targets to maximise benefit and minimise harm.
•There is wide variation in needle biopsy rates in the English NHS breast screening programme.•Increasing needle biopsy rates leads to a rapid increase in false positive needle biopsies.•Needle biopsy rate target ranges should be considered along with recall rate target ranges.
There is limited information about participation in organised population-wide screening programmes by people with disabilities.
Data from the National Health Service routine screening programmes in ...England were linked to information on disability reported by the Million Women Study cohort participants.
Of the 473 185 women offered routine breast or bowel cancer screening, 23% reported some disability. Women with disabilities were less likely than other women to participate in breast cancer screening (RR=0.64, 95% CI: 0.62-0.65) and in bowel cancer screening (RR=0.75, 0.73-0.76). Difficulties with self-care or vision were associated with the greatest reduction in screening participation.
Participation in routine cancer screening programmes in England is reduced in people with disabilities and participation varies by type of disability.
In 2006, the National Health Service Bowel Cancer Screening Programme in England (NHSBCSP) began offering routine population-based biennial faecal occult blood testing (FOBt) at ages 60-69. There is, ...however, limited information on how characteristics of individuals affect participation and outcomes of screening, and we studied this association by linking NHSBCSP data to a large prospective cohort of women.
Electronic linkage of the NHSBCSP and Million Women Study records identified 899 166 women in the study cohort with at least one invitation for screening. NHSBCSP provided information on screening acceptance, FOBt results, screen-detected colorectal cancer and other outcomes. The Million Women Study provided prospectively collected information on personal and lifestyle factors. Multiple regression was used to estimate relative risks (RRs) of factors associated with acceptance and outcomes of screening.
Overall, 70% of women (628 976/899 166) accepted their first invitation for bowel cancer screening, of whom 9133 (1.5%) were FOBt-positive, 743 (0.1%) had screen-detected colorectal cancer and 3056 (0.5%) had screen-detected colorectal adenoma. Acceptance was lower in women from the most than the least deprived tertile, in South Asians and in Blacks than in Whites, in current than in never smokers and in obese than in normal weight women: adjusted RRs (95% confidence interval) for acceptance vs not, 0.90 (0.90-0.90); 0.77 (0.75-79); 0.94 (0.92-0.96); 0.78 (0.77-0.78); and 0.88 (0.88-0.89), respectively: P<0.001 for each. These factors were also associated with an increased risk of being FOBt-positive and of having screen-detected adenoma, but were not strongly associated with the risk of screen-detected colorectal cancer. Relative risks for screen-detected adenoma were 1.22 (1.12-1.34), 2.46 (1.75-3.45), 1.61 (1.05-2.48), 1.53 (1.38-1.68) and 1.77 (1.60-1.95), respectively (P<0.001 for all, except for Blacks vs Whites P=0.03). Use of hormone therapy for menopause was associated with reduced risk of screen-detected adenoma, RR ever vs never use, 0.87 (0.81-0.93), P<0.001 and colorectal cancer, 0.78 (0.68-0.91), P=0.001.
Among women in England, socioeconomic and lifestyle factors strongly affect participation in routine bowel cancer screening, risk of being FOBt-positive and risk of having screen-detected colorectal adenoma. However, screen-detected colorectal cancer risk is not strongly related to these factors.
The NHS Breast Screening Programme (NHSBSP) was started in 1988 and is a large, organised cancer screening programme. It is delivered by 80 services across England and screens over 2 million women ...each year. As a screening programme, it must balance the detection of cancers against possible harm to women who do not have cancer. The NHSBSP was therefore designed with detailed information gathering and performance metrics right from the start. In this review paper, we examine how performance metrics in screening mammography have improved the national screening programme and the further developments and challenges that are expected in the years to come.
Gordon Brown has pledged to increase screening services in the NHS. Muir Gray, Julietta Patnick, and Roger Blanks show how experience with the UK breast screening programme can help ensure that they ...are effective
R.G. Blanks ABC3 Part II: a review of the new criteria for evaluating cervical cytology in England
The new Achievable Standards, Benchmarks for Reporting, and Criteria for Evaluating Cervical ...Cytopathology, 3rd edn (ABC3) includes radical changes in the criteria for evaluating cervical cytology. First, they include a new mission statement ‘the objective of cervical screening is to reduce cervical cancer incidence and mortality by screening with a high sensitivity for the detection of CIN2 or worse, whilst maintaining a high specificity’.
Second, the original four performance measurement criteria where laboratories were examined further if they were below the 10th or above the 90th percentile has been changed to three and laboratories are only mandatorily examined if they fall below the 5th or above the 95th percentile. The old criteria related to the percentage of samples that were inadequate, the percentage of all adequate samples reported as moderate dyskaryosis or worse (equivalent to high‐grade squamous intraepithelial lesion or cancer), the percentage of adequate samples reported as mild dyskaryosis or borderline (equivalent to low‐grade squamous intraepithelial lesion or atypical squamous/glandular cells) and the positive predictive value. The new criteria are percentage of inadequate samples, positive predictive value and a new measure termed referral value. These changes mean that far fewer laboratories will require mandatory examination.
Third, a raft of optional performance measures have been introduced to help laboratories examine their annual statistical return to the Department of Health in comparison with other laboratories. These measures have been designed to produce a more uniform national programme, and to help laboratories decide whether they are maximizing the benefit of screening while minimizing the harm, which is the goal of all screening programmes. This review examines in detail the new criteria and explains in more detail some of the thinking behind them.
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