Artificial intelligence in digital pathology: a diagnostic test accuracy systematic review and meta-analysis

Ensuring diagnostic performance of AI models before clinical use is key to the safe and successful adoption of these technologies. Studies reporting AI applied to digital pathology images for diagnostic purposes have rapidly increased in number in recent years. The aim of this work is to provide an overview of the diagnostic accuracy of AI in digital pathology images from all areas of pathology. This systematic review and meta-analysis included diagnostic accuracy studies using any type of artificial intelligence applied to whole slide images (WSIs) in any disease type. The reference standard was diagnosis through histopathological assessment and / or immunohistochemistry. Searches were conducted in PubMed, EMBASE and CENTRAL in June 2022. We identified 2976 studies, of which 100 were included in the review and 48 in the full meta-analysis. Risk of bias and concerns of applicability were assessed using the QUADAS-2 tool. Data extraction was conducted by two investigators and meta-analysis was performed using a bivariate random effects model. 100 studies were identified for inclusion, equating to over 152,000 whole slide images (WSIs) and representing many disease types. Of these, 48 studies were included in the meta-analysis. These studies reported a mean sensitivity of 96.3% (CI 94.1-97.7) and mean specificity of 93.3% (CI 90.5-95.4) for AI. There was substantial heterogeneity in study design and all 100 studies identified for inclusion had at least one area at high or unclear risk of bias. This review provides a broad overview of AI performance across applications in whole slide imaging. However, there is huge variability in study design and available performance data, with details around the conduct of the study and make up of the datasets frequently missing. Overall, AI offers good accuracy when applied to WSIs but requires more rigorous evaluation of its performance.Comment: 26 pages, 5 figures, 8 tables + Supplementary material

The NAtional randomised controlled Trial of Tonsillectomy IN Adults (NATTINA) : a clinical and cost-effectiveness study: study protocol for a randomised control trial

This project is funded by the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme (project number 12/146/06).BACKGROUND: The role of tonsillectomy in the management of adult tonsillitis remains uncertain and UK regional variation in tonsillectomy rates persists. Patients, doctors and health policy makers wish to know the costs and benefits of tonsillectomy against conservative management and whether therapy can be better targeted to maximise benefits and minimise risks of surgery, hence maximising cost-effective use of resources. NATTINA incorporates the first attempt to map current NHS referral criteria against other metrics of tonsil disease severity. METHODS/DESIGN: A UK multi-centre, randomised, controlled trial for adults with recurrent tonsillitis to compare the clinical and cost-effectiveness of tonsillectomy versus conservative management. An initial feasibility study comprises qualitative interviews to investigate the practicality of the protocol, including willingness to randomise and be randomised. Approximately 20 otolaryngology staff, 10 GPs and 15 ENT patients will be recruited over 5 months in all 9 proposed main trial participating sites. A 6-month internal pilot will then recruit 72 patients across 6 of the 9 sites. Participants will be adults with recurrent acute tonsillitis referred by a GP to secondary care. Randomisation between tonsillectomy and conservative management will be according to a blocked allocation method in a 1:1 ratio stratified by centre and baseline disease severity. If the pilot is successful, the main trial will recruit a further 528 patients over 18 months in all 9 participating sites. All participants will be followed up for a total of 24 months, throughout which both primary and secondary outcome data will be collected. The primary outcome is the number of sore throat days experienced over the 24-month follow-up. The pilot and main trials include an embedded qualitative process evaluation. DISCUSSION: NATTINA is designed to evaluate the relative effectiveness and efficiency of tonsillectomy versus conservative management in patients with recurrent sore throat who are eligible for surgery. Most adult tonsil disease and surgery has an impact on economically active age groups, with individual and societal costs through loss of earnings and productivity. Avoidance of unnecessary operations and prioritisation of those individuals likely to gain most from tonsillectomy would reduce costs to the NHS and society. TRIAL REGISTRATION: ISRCTN55284102, Date of Registration: 4 August 2014.Publisher PDFPeer reviewe

Use of proton pump inhibitors to treat persistent throat symptoms: Multicentre, double blind, randomised, placebo controlled trial

Objective. To assess the use of proton pump inhibitors (PPIs) to treat persistent throat symptoms. Design. Pragmatic, double blind, placebo controlled, randomised trial. Setting. Eight ear, nose, and throat outpatient clinics, United Kingdom. Participants. 346 patients aged 18 years or older with persistent throat symptoms who were randomised according to recruiting centre and baseline severity of symptoms (mild or severe): 172 to lansoprazole and 174 to placebo. Intervention. Random blinded allocation (1:1) to either 30 mg lansoprazole twice daily or matched placebo twice daily for 16 weeks. Main outcome measures. Primary outcome was symptomatic response at 16 weeks measured using the total reflux symptom index (RSI) score. Secondary outcomes included symptom response at 12 months, quality of life, and throat appearances. Results. Of 1427 patients initially screened for eligibility, 346 were recruited. The mean age of the study sample was 52.2 (SD 13.7) years, 196 (57%) were women, and 162 (47%) had severe symptoms at presentation; these characteristics were balanced across treatment arms. The primary analysis was performed on 220 patients who completed the primary outcome measure within a window of 14-20 weeks. Mean RSI scores were similar between treatment arms at baseline: lansoprazole 22.0 (95% confidence interval 20.4 to 23.6) and placebo 21.7 (20.5 to 23.0). Improvements (reduction in RSI score) were observed in both groups—score at 16 weeks: lansoprazole 17.4 (15.5 to19.4) and placebo 15.6 (13.8 to 17.3). No statistically significant difference was found between the treatment arms: estimated difference 1.9 points (95% confidence interval −0.3 to 4.2 points; P=0.096) adjusted for site and baseline symptom severity. Lansoprazole showed no benefits over placebo for any secondary outcome measure, including RSI scores at 12 months: lansoprazole 16.0 (13.6 to 18.4) and placebo 13.6 (11.7 to 15.5): estimated difference 2.4 points (−0.6 to 5.4 points). Conclusions. No evidence was found of benefit from PPI treatment in patients with persistent throat symptoms. RSI scores were similar between the lansoprazole and placebo groups after 16 weeks of treatment and at the 12 month follow-up

The value of source data verification in a cancer clinical trial

Background Source data verification (SDV) is a resource intensive method of quality assurance frequently used in clinical trials. There is no empirical evidence to suggest that SDV would impact on comparative treatment effect results from a clinical trial. Methods Data discrepancies and comparative treatment effects obtained following 100% SDV were compared to those based on data without SDV. Overall survival (OS) and Progression-free survival (PFS) were compared using Kaplan-Meier curves, log-rank tests and Cox models. Tumour response classifications and comparative treatment Odds Ratios (ORs) for the outcome objective response rate, and number of Serious Adverse Events (SAEs) were compared. OS estimates based on SDV data were compared against estimates obtained from centrally monitored data. Findings Data discrepancies were identified between different monitoring procedures for the majority of variables examined, with some variation in discrepancy rates. There were no systematic patterns to discrepancies and their impact was negligible on OS, the primary outcome of the trial (HR (95% CI): 1.18(0.99 to 1.41), p = 0.064 with 100% SDV; 1.18(0.99 to 1.42), p = 0.068 without SDV; 1.18(0.99 to 1.40), p = 0.073 with central monitoring). Results were similar for PFS. More extreme discrepancies were found for the subjective outcome overall objective response (OR (95% CI): 1.67(1.04 to 2.68), p = 0.03 with 100% SDV; 2.45(1.49 to 4.04), p = 0.0003 without any SDV) which was mostly due to differing CT scans. Interpretation Quality assurance methods used in clinical trials should be informed by empirical evidence. In this empirical comparison, SDV was expensive and identified random errors that made little impact on results and clinical conclusions of the trial. Central monitoring using an external data source was a more efficient approach for the primary outcome of OS. For the subjective outcome objective response, an independent blinded review committee and tracking system to monitor missing scan data could be more efficient than SDV

Rationale and design of the LIBERATES trial: Protocol for a randomised controlled trial of flash glucose monitoring for optimisation of glycaemia in individuals with type 2 diabetes and recent myocardial infarction.

Hyperglycaemia in individuals with type 2 diabetes (T2D) and myocardial infarction (MI) is associated with guarded clinical prognosis. Studies improving glucose levels in T2D following MI relied on HbA1c as the main glycaemic marker, failing to address potential adverse effects of hypoglycaemia and glucose variability. We describe the design of the LIBERATES trial that investigates the role of flash glucose monitoring in optimising glycaemic markers in high vascular risk individuals with T2D. This multicentre trial is designed to recruit up to 150 insulin and/or sulphonylurea-treated T2D patients, within 5 days of a proven MI. Individuals will be randomised 1:1 into intervention and control groups using flash glucose monitoring sensors and traditional self-monitoring of blood glucose, respectively. The control group will also wear a blinded continuous glucose monitoring sensor. The primary outcome is the difference in time spent in euglycaemia (defined as glucose levels between 3.9-10.0 mmol/l), comparing study groups 3 months following recruitment, assessed daily for 14 days and as an average. Secondary and exploratory end points include time spent in hypoglycaemia and hyperglycaemia, HbA1c, quality of life measures, major adverse cardiac events and cost-effectiveness of the intervention. This study will establish the role of flash glucose monitoring in glycaemic management of individuals with T2D sustaining a cardiac event.(Trial Registration: ISRCTN14974233, registered 12th June 2017)

Establishing the added benefit of measuring MMP9 in FOB positive patients as a part of the Wolverhampton colorectal cancer screening programme

<p>Abstract</p> <p>Background</p> <p>Bowel cancer is common and a major cause of death. The NHS is currently rolling out a national bowel cancer screening programme that aims to cover the entire population by 2010. The programme will be based on the Faecal Occult Blood test (FOBt) that reduces mortality from colon cancer by 16%. However, FOB testing has a relatively low positive predictive value, with associated unnecessary cost, risk and anxiety from subsequent investigation, and is unacceptable to a proportion of the target population. Increased levels of an enzyme called matrix metalloproteinase 9 (MMP9) have been found to be associated with colorectal cancer, and this can be measured from a blood sample. MMP9 has potential for detecting those at risk of having colorectal cancer. The aim of this study is to assess whether MMP9 estimation enhances the predictive value of a positive FOBt.</p> <p>Methods and design</p> <p>FOBt positive people aged 60–69 years attending the Wolverhampton NHS Bowel Cancer Screening Unit and providing consent for colonoscopy will be recruited. Participants will provide a blood sample prior to colonoscopy and permission for collection of the clinical outcome from screening unit records. Multivariate logistic regression analyses will determine the independent factors (patient and disease related, MMP9) associated with the prediction of neoplasia.</p> <p>Discussion</p> <p>Colorectal cancer is a major cause of morbidity and mortality. Pilot studies have confirmed the feasibility of the national cancer screening programme that is based on FOBt. However, the test has high false positive rates. MMP9 has significant potential as a marker for both adenomas and cancers. This study is to examine whether using MMP9 as an adjunct to FOBt improves the accuracy of screening and reduces the number of false positive tests that cause anxiety and require invasive and potentially harmful investigation.</p

A randomised, placebo controlled trial of extra-oesophageal reflux treatment in the management of upper respiratory symptoms [TOPPITS:Trial of Proton Pump Inhibitors in Throat Symptoms]

Background. Persistent throat symptoms, such as throat clearing, globus sensation, voice change and catarrh are extremely common. On very limited evidence, they are increasingly attributed to “laryngopharyngeal reflux (LPR)” and treated with proton pump inhibitors (PPIs) in primary and secondary care. Methods. A double blind placebo controlled UK multicentre phase III trial randomly allocated adults with persistent throat symptoms 1:1 to either 30 mg of Lansoprazole or matched placebo twice daily for 16 weeks, stratified by centre and symptom severity. The primary outcome was patient-reported symptomatic response, measured by the total Reflux Symptom Index (RSI) score at the end of therapy. Secondary outcomes included safety, further symptoms and quality of life measures at 12-months. Results. 346 participants were randomised from 8 UK centres: mean (sd) age 52 (13), 196 (57%) female, 162 (47%) severe symptoms, balanced across randomised groups. Mean RSI scores (95% CI) were similar at baseline- Lansoprazole: 22.0 (20.4, 23.6), placebo: 21.7 (20.5, 23.0). Improvements (reduction in score) were observed in both groups at 16-weeks: Lansoprazole: 17.4 (15.5, 19.4), placebo: 15.6 (13.8, 17.3) (p=0.096 adjusted by site, severity). There was no statistically significant difference between randomised groups. No significant differences were observed in the secondary outcome measures. Conclusions. TOPPITS is the largest, definitive trial to assess PPI effectiveness for persistent throat symptoms. It found no advantage of Lansoprazole over placebo in a range of outcomes. The near routine use of PPIs for throat symptoms should be discontinued

Effectiveness of GRACE risk score in patients admitted to hospital with non-ST elevation acute coronary syndrome (UKGRIS): parallel group cluster randomised controlled trial

OBJECTIVE: To determine the effectiveness of risk stratification using the Global Registry of Acute Coronary Events (GRACE) risk score (GRS) for patients presenting to hospital with suspected non-ST elevation acute coronary syndrome. DESIGN: Parallel group cluster randomised controlled trial. SETTING: Patients presenting with suspected non-ST elevation acute coronary syndrome to 42 hospitals in England between 9 March 2017 and 30 December 2019. PARTICIPANTS: Patients aged ≥18 years with a minimum follow-up of 12 months. INTERVENTION: Hospitals were randomised (1:1) to patient management by standard care or according to the GRS and associated guidelines. MAIN OUTCOME MEASURES: Primary outcome measures were use of guideline recommended management and time to the composite of cardiovascular death, non-fatal myocardial infarction, new onset heart failure hospital admission, and readmission for cardiovascular event. Secondary measures included the duration of hospital stay, EQ-5D-5L (five domain, five level version of the EuroQoL index), and the composite endpoint components. RESULTS: 3050 participants (1440 GRS, 1610 standard care) were recruited in 38 UK clusters (20 GRS, 18 standard care). The mean age was 65.7 years (standard deviation 12), 69% were male, and the mean baseline GRACE scores were 119.5 (standard deviation 31.4) and 125.7 (34.4) for GRS and standard care, respectively. The uptake of guideline recommended processes was 77.3% for GRS and 75.3% for standard care (odds ratio 1.16, 95% confidence interval 0.70 to 1.92, P=0.56). The time to the first composite cardiac event was not significantly improved by the GRS (hazard ratio 0.89, 95% confidence interval 0.68 to 1.16, P=0.37). Baseline adjusted EQ-5D-5L utility at 12 months (difference -0.01, 95% confidence interval -0.06 to 0.04) and the duration of hospital admission within 12 months (mean 11.2 days, standard deviation 18 days v 11.8 days, 19 days) were similar for GRS and standard care. CONCLUSIONS: In adults presenting to hospital with suspected non-ST elevation acute coronary syndrome, the GRS did not improve adherence to guideline recommended management or reduce cardiovascular events at 12 months. TRIAL REGISTRATION: ISRCTN 29731761

Conservative management versus tonsillectomy in adults with recurrent acute tonsillitis in the UK (NATTINA) : a multicentre, open-label, randomised controlled trial

This study was funded by the NIHR Health Technology Assessment programme (12/146/06).Background Tonsillectomy is regularly performed in adults with acute tonsillitis, but with scarce evidence. A reduction in tonsillectomies has coincided with an increase in acute adult hospitalisation for tonsillitis complications. We aimed to assess the clinical effectiveness and cost-effectiveness of conservative management versus tonsillectomy in patients with recurrent acute tonsillitis. Methods This pragmatic multicentre, open-label, randomised controlled trial was conducted in 27 hospitals in the UK. Participants were adults aged 16 years or older who were newly referred to secondary care otolaryngology clinics with recurrent acute tonsillitis. Patients were randomly assigned (1:1) to receive tonsillectomy or conservative management using random permuted blocks of variable length. Stratification by recruiting centre and baseline symptom severity was assessed using the Tonsil Outcome Inventory-14 score (categories defined as mild 0–35, moderate 36–48, or severe 49–70). Participants in the tonsillectomy group received elective surgery to dissect the palatine tonsils within 8 weeks after random assignment and those in the conservative management group received standard non-surgical care during 24 months. The primary outcome was the number of sore throat days collected during 24 months after random assignment, reported once per week with a text message. The primary analysis was done in the intention-to-treat (ITT) population. This study is registered with the ISRCTN registry, 55284102. Findings Between May 11, 2015, and April 30, 2018, 4165 participants with recurrent acute tonsillitis were assessed for eligibility and 3712 were excluded. 453 eligible participants were randomly assigned (233 in the immediate tonsillectomy group vs 220 in the conservative management group). 429 (95%) patients were included in the primary ITT analysis (224 vs 205). The median age of participants was 23 years (IQR 19–30), with 355 (78%) females and 97 (21%) males. Most participants were White (407 [90%]). Participants in the immediate tonsillectomy group had fewer days of sore throat during 24 months than those in the conservative management group (median 23 days [IQR 11–46] vs 30 days [14–65]). After adjustment for site and baseline severity, the incident rate ratio of total sore throat days in the immediate tonsillectomy group (n=224) compared with the conservative management group (n=205) was 0·53 (95% CI 0·43 to 0·65;Publisher PDFPeer reviewe