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Background Quantitative faecal immunochemical tests measure faecal haemoglobin concentration (f-Hb), which increases in the presence of colorectal neoplasia. Objective We examined the diagnostic accuracy of faecal immunochemical test (FIT)in patients at increased risk of colorectal cancer (CRC) attending for surveillance colonoscopy as per national guidelines. Methods A total of 1103 consecutive patients were prospectively invited to complete a FIT before their scheduled colonoscopy in two university hospitals in 2014– 2016. F-Hb was analysed on an OC-Sensor io automated analyser (Eiken Chemical Co., Ltd, Tokyo, Japan) with a limit of detection of 2 µg Hb/g faeces. The diagnostic accuracy of f-Hb for CRC and higher-risk adenoma was examined. Results A total of 643 patients returned a faecal test. After excluding 4 patients with known inflammatory bowel disease, 639 (57.9%) remained in the study: age range: 25–90 years (median: 64 years, interquartile range (IQR): 55–71): 54.6% male. Of 593 patients who also completed colonoscopy, 41 (6.9%) had advanced neoplasia (4 CRC, 37 higher-risk adenoma). Of the 238 patients (40.1%) who had detectable f-Hb, 31 (13.0%) had advanced neoplasia (2 CRC, 29 higher-risk adenoma) compared with 10 (2.8%) in those with undetectable f-Hb (2 CRC, 8 higher-risk adenoma). Detectable f-Hb gave negative predictive values of 99.4% for CRC and 97.2% for CRC plus higher-risk adenoma. Conclusion In patients at increased risk of CRC under colonoscopy surveillance, a test measuring faecal haemoglobin can provide an objective estimate of the risk of advanced neoplasia, and could enable tailored scheduling of colonoscopy.

Aim The delivery of the Scottish Bowel Screening Programme (SBoSP) is rooted in the provision of a high quality, effective and participant-centred service. Safe and effective colonoscopy forms an integral part of the process. Additional accreditation as part of a multi-faceted programme for participating colonoscopists, as in England, does not exist in Scotland. This study aimed to describe the quality of colonoscopy in the SBoSP and compare this to the English national screening standards. Methods Data were collected from the SBoSP between 2007 and 2014. End-points for analysis were caecal intubation, cancer, polyp and adenoma detection, and complications. Overall results were compared with 2012 published English national standards for screening and outcomes from 2006 to 2009. Results During the study period 53 332 participants attended for colonoscopy. The colonoscopy completion rate was 95.6% overall. The mean cancer detection rate was 7.1%, the polyp detection rate was 45.7% and the adenoma detection rate was 35.5%. The overall complication rate was 0.47%. Conclusion Colonoscopy quality in the SBoSP has exceeded the standard set for screening colonoscopy in England, despite not adopting a multi-faceted programme for screening colonoscopy. However, the overall adenoma detection rate in Scotland was 9.1% lower than that in England which has implications for colonoscopy quality and may have an impact on cancer prevention rates, a key aim of the SBoSP.

Prediction models for colorectal cancer (CRC) detection in symptomatic patients, based on easily obtainable variables such as fecal haemoglobin concentration (f-Hb), age and sex, may simplify CRC diagnosis. We developed, and then externally validated, a multivariable prediction model, the FAST Score, with data from five diagnostic test accuracy studies that evaluated quantitative fecal immunochemical tests in symptomatic patients referred for colonoscopy. The diagnostic accuracy of the Score in derivation and validation cohorts was compared statistically with the area under the curve (AUC) and the Chi-square test. 1,572 and 3,976 patients were examined in these cohorts, respectively. For CRC, the odds ratio (OR) of the variables included in the Score were: age (years): 1.03 (95% confidence intervals (CI): 1.02–1.05), male sex: 1.6 (95% CI: 1.1–2.3) and f-Hb (0–

Aim In guaiac faecal occult blood test (gFOBT) screening at least 50% of positive individuals will have a colonoscopy negative for colorectal neoplasia. The question of continuing screening in this group has not been addressed. Method Data on participants aged 50–69 years with a positive gFOBT result and a negative colonoscopy were followed through the biennial screening pilot conducted between 2000 and 2007 in Scotland. Results In the first screening round, 1527 colonoscopies were negative for neoplasia. 1300 were re-invited in the second round, 905 accepted, and 157 had a positive gFOBT result, giving a positivity rate of 17.4%. Colonoscopy revealed 20 subjects with adenoma and six with invasive cancer. In the third screening round 1031 were invited for a third time and 730 accepted: 55 had a positive gFOBT test, giving a positivity rate of 7.5%. In this group, six colonoscopies revealed adenomas but there were no cancers diagnosed. In the third screening round, 108 individuals had had two positive gFOBT results and two subsequent negative colonoscopies. Eighty-four were invited for a third gFOBT, 66 accepted and 19 (25.6%) had a positive result none of whom had an adenoma or carcinoma. Conclusion These data indicate that a negative colonoscopy following a positive gFOBT is not a contraindication for further screening, although this is likely to have a low yield of neoplastic pathology after two negative colonoscopies.

Assessment of the relative clinical usefulness of glycosylated haemoglobin (HbA1) and serum fructosamine is complicated by their markedly different half-lives. They have therefore been compared using a number of indices derived from data on biological variation, as applied in a study of blood glucose control in newly diagnosed diabetic patients. The within-subject (CVI) and between-subject (CVG) variation of fructosamine and HbA1 were assessed in 8 stable diabetic patients. A slightly smaller relative change, or critical difference, is required between serial HbA1 results than between fructosamine results before a significant change can be said to have occurred. The heterogeneity of within-subject variance is also less for HbA1, rendering the critical difference more generally applicable. HbA1 may therefore be more appropriate for long-term monitoring. Monitoring of blood glucose control of a group of 26 newly diagnosed diabetic patients before the commencement of therapy and 1, 2, and 3 months later by serum fructosamine or HbA1 provided very similar information. Fructosamine responds more rapidly with changes of blood glucose control. However, whether this confers any clinical advantage will depend upon the frequency of testing.