The contribution of a negative colorectal screening test result to symptom appraisal and help-seeking behaviour among patients subsequently diagnosed with an interval colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) screening programmes using a guaiac faecal occult blood test (gFOBt) reduce CRC mortality. Interval cancers are diagnosed between screening rounds: reassurance from a negative gFOBt has the potential to influence the pathway to diagnosis of an interval colorectal cancer. METHODS: Twenty-six semi-structured face-to-face interviews were carried out in Scotland and England, with individuals diagnosed with an interval colorectal cancer following a negative gFOBt result. RESULTS: Participants reported they were reassured by a negative gFOBt, interpreting their result as an "all clear". Therefore, most did not suspect cancer as a possible cause of symptoms and many did not recall their screening result during symptom appraisal. Among those who did consider cancer, and did think about their screening test result, reassurance from a negative gFOBt led some to "downplay" the seriousness of their symptoms with some interviewees explicitly stating that their negative test result contributed to a delayed decision to seek help. CONCLUSION: Screening participants need to be informed of the limitations of screening and the ongoing risk of developing colorectal cancer even when in receipt of a negative result: the importance of minimizing delay in seeking medical advice for colorectal symptoms should be emphasized.

Understanding of a negative bowel screening result and potential impact on future symptom appraisal and help-seeking behaviour: a focus group study.

BACKGROUND: Colorectal cancer (CRC) screening using a faecal occult blood test (FOBt) has the potential to reduce cancer-related mortality. Symptom vigilance remains crucial as a proportion of cancers will be diagnosed between screening rounds. A negative FOBt has the potential to influence how participants respond to future symptoms of CRC. OBJECTIVE: To explore (i) understanding of a negative FOBt and (ii) the potential impact of a negative FOBt upon future symptom appraisal and help-seeking behaviour. DESIGN: Qualitative methodology utilizing focus groups with participants who received a negative FOBt within the National Bowel Cancer Screening Programme in Coventry and Lothian. Topics explored included: experience of screening participation, interpretation and understanding of a negative result, symptom awareness and attitudes towards help-seeking. RESULTS: Four broad themes were identified: (i) emotional response to a negative FOBt, (ii) understanding the limitations of FOBt screening, (iii) symptom knowledge and interpretation and (iv) over-reassurance from a negative FOBt. Participants were reassured by a negative FOBt, but there was variability in the extent to which the result was interpreted as an "all clear". Some participants acknowledged the residual risk of cancer and the temporal characteristic of the result, while others were surprised that the result was not a guarantee that they did not have cancer. DISCUSSION AND CONCLUSIONS: Participants recognized that reassurance from a negative FOBt could lead to a short-term delay in help-seeking if symptoms developed. Screening programmes should seek to emphasize the importance of the temporal nature of FOBt results with key messages about symptom recognition and prompt help-seeking behaviour.

Evaluation of the use of digital images for a national prostate core external quality assurance scheme.

AIMS: To evaluate the use of virtual images as an alternative to glass slides to expand the number of participants in the External Quality Assurance Scheme for prostatic biopsies. METHODS AND RESULTS: Benign and neoplastic cases, previously circulated as glass slides, were selected to include cases that had demonstrated a high level of agreement (n = 10) and a lesser degree of agreement (n = 10). Whole slide virtual images were circulated to 68 pathologists; 51 responses were returned. The levels of agreement for the primary diagnosis and for Gleason grading of cancers were analysed using kappa statistics. Responses for glass slides versus images were compared for the 24 pathologists for whom data were available. Levels of agreement for diagnostic categories using virtual slides were moderate to substantial, comparable to those found using glass slides. The level of agreement for Gleason grades 8-10 was substantial, but for lower grades was fair or moderate, poorer than for the glass slide circulation. CONCLUSIONS: Circulation of virtual images of biopsy material is a suitable alternative to glass slide-based schemes for the evaluation of diagnostic consistency. The majority of participants agreed that the ability to evaluate limited diagnostic material outweighed the disadvantages of a virtual system.

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.

Seasonal variation in diagnosis of invasive cutaneous melanoma in Eastern England and Scotland.

BACKGROUND: Worldwide, the incidence of cutaneous melanoma has been reported to be highest in the summer and lowest in the winter. Northern Irish data suggested seasonal variation for women only, especially those with thinner melanomas, sited on limbs. We interrogated two larger UK cancer registries for temporal differences in melanoma diagnosis and associated patient characteristics. METHODS: Melanomas diagnosed from 2006 to 2010 in the Eastern England and Scottish cancer registries (n=11,611) were analysed by month of diagnosis, patient demographics and melanoma characteristics, using descriptive and multivariate modelling methods. RESULTS: More patients with melanoma were diagnosed in the summer months (June 9.9%, July 9.7%, August 9.8%) than the winter months (December 7.2%, January 7.2%, February 7.1%) and this pattern was consistent in both regions. There was evidence that the seasonal patterns varied by sex (p=0.015), melanoma thickness (p=0.002), body site (p=0.006), and type (superficial spreading melanomas p=0.005). The seasonal variation was greatest for diagnosis of melanomas occurring on the limbs. CONCLUSION: This study has confirmed seasonal variation in melanoma diagnosis in Eastern England and Scotland across almost all population demographics and melanoma characteristics studied, with higher numbers diagnosed in the summer months, particularly on the limbs. Seasonal patterns in skin awareness and related help-seeking are likely to be implicated. Targeted patient interventions to increase sun awareness and encourage year-long skin inspection are warranted.

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.

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 (κ(p-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 κ(p-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.

Bayesian belief network for the Gleason patterns in prostatic adenocarcinoma: development of a diagnostic decision support system for educational purposes.

OBJECTIVE: To develop a Bayesian belief network (BBN) for Gleason grading of prostate adenocarcinoma. STUDY DESIGN: A shallow network was developed for Gleason grading with open-tree topology, with a root node containing 5 subjective diagnostic alternatives and 8 first-level descendant nodes for diagnostic features. Features or diagnostic clues of the descendant nodes were based on architecture of Gleason patterns. Data collected on 20 slides in the first and third slide circulations in the U.K.-based investigation of observer reproducibility of Gleason grading of prostatic biopsies were used. Circulations were called A and B. Level of agreement was studied using kappa statistics. RESULTS: Mean of percentage agreements between subjective Gleason major pattern attributed to slides by pathologists and subjective Gleason major pattern most frequently assigned to each slide was 85% in A and 88% in B. Mean of percentage agreements between BBN reading for slides read by pathologists and BBN reading most frequently seen in each slide was 77% in A and 70% in B. CONCLUSION: The BBN for Gleason grading is readily implemented, allowing use of linguistic variables and descriptive terms and accumulation of evidence presented by morphologic clues. This diagnostic decision support system has potential in pathology education.

Rates of prostate-specific antigen testing in general practice in England and Wales in asymptomatic and symptomatic patients: a cross-sectional study.

OBJECTIVE: To assess the rate of prostate-specific antigen (PSA) testing for prostate cancer in general practice in asymptomatic and symptomatic patients. SUBJECTS AND METHODS: The cross-sectional study took place in England and Wales, was population-based and covered 469 159 men aged 45-84 years. Pathology data on PSA tests requested between 19 November 1999 and 31 May 2002 by general practitioners (GPs) were provided by 28 pathology laboratories. The practices recorded reasons for the tests between 1 December 2001 and 31 May 2002. In all, 391 practices in which all GP partners participated were included in the analyses. RESULTS: The overall annual rate of testing in men with no previous diagnosis of prostate cancer was estimated to be 6%, of which the annual rates of asymptomatic, symptomatic and re-testing were 2.0%, 2.8% and 1.2%, respectively, after adjusting for missing values. The rate decreased with increasing social deprivation, and with increasing proportions of black and Asian populations. The overall rate of PSA testing increased significantly from 1999 to 2002. CONCLUSIONS: If the recommendations of the National Health Service Prostate Cancer Risk Management Programme were applied, 14% of asymptomatic tests and 23% of symptomatic tests would have led to a referral. As the rate of PSA testing is increasing and there are uncertainties about the benefit of screening, the workload and costs in general practice and hospitals should be monitored.