Variation in Pathologist Classification of Colorectal Adenomas and Serrated Polyps.
ABSTRACT: OBJECTIVES:Endoscopist quality measures such as adenoma detection rate (ADR) and serrated polyp detection rates (SPDRs) depend on pathologist classification of histology. Although variation in pathologic interpretation is recognized, we add to the literature by quantifying the impact of pathologic variability on endoscopist performance. METHODS:We used natural language processing to abstract relevant data from colonoscopy and related pathology reports performed over 2 years at four clinical sites. We quantified each pathologist's likelihood of classifying polyp specimens as adenomas or serrated polyps. We estimated the impact on endoscopists' ADR and SPDR of sending their specimens to pathologists with higher or lower classification rates. RESULTS:We observed 85,526 colonoscopies performed by 119 endoscopists; 50,453 had a polyp specimen, which were analyzed by 48 pathologists. There was greater variation across pathologists in classification of serrated polyps than in classification of adenomas. We estimate the endoscopist's average SPDR would be 0.5% if all their specimens were analyzed by the pathologist in our sample with the lowest classification rate and 12.0% if all their specimens were analyzed by the pathologist with the highest classification rate. In contrast, the endoscopist's average ADR would be 28.5% and 42.4% if their specimens were analyzed by the pathologist with lowest and highest classification rate, respectively. CONCLUSIONS:There is significant variation in pathologic interpretation, which more substantially affects endoscopist SPDR than ADR.
Project description:BACKGROUND:Serrated polyps are important colorectal cancer precursors that are variably detected during colonoscopy. We measured serrated polyp detection rate (SPDR) in a large, multicenter, cross-sectional study of colonoscopy quality to identify drivers of SPDR variation. METHODS:Colonoscopy and pathology reports were collected for a 2-year period (10/2013-9/2015) from four sites across the United States. Data from reports, including size, location, and histology of polyps, were abstracted using a validated natural language processing algorithm. SPDR was defined as the proportion of colonoscopies with ??1 serrated polyp (not including hyperplastic polyps). Multivariable logistic regression was performed to determine endoscopist characteristics associated with serrated polyp detection. RESULTS:A total of 104?618 colonoscopies were performed by 201 endoscopists who varied with respect to specialty (86?% were gastroenterologists), sex (18?% female), years in practice (range 1?-?51), and number of colonoscopies performed during the study period (range 30?-?2654). The overall mean SPDR was 5.1?% (SD 3.8?%, range 0?-?18.8?%). In multivariable analysis, gastroenterology specialty training (odds ratio [OR] 1.89, 95?% confidence interval [CI] 1.33?-?2.70), fewer years in practice (??9 years vs. ??27 years: OR 1.52, 95?%CI 1.14?-?2.04)], and higher procedure volumes (highest vs. lowest quartile: OR 1.77, 95?%CI 1.27?-?2.46)] were independently associated with serrated polyp detection. CONCLUSIONS:Gastroenterology specialization, more recent completion of training, and greater procedure volume are associated with serrated polyp detection. These findings imply that both repetition and training are likely to be important contributors to adequate detection of these important cancer precursors. Additional efforts to improve SPDR are needed.
Project description:Introduction:Quality measures for colonoscopy such as adenoma detection rate (ADR) have been proposed to be surveilled for ensuring minimum standards. However, its direct measurement is time consuming and often neglected. Extrapolating ADR and other quality measures from polyp detection rate (PDR) can be a pragmatic alternative. Objective:To determine quotients for estimating ADR and sessile serrated adenoma/polyp detection rate (SSA/P-DR) from PDR in an Australian cohort. Methods:Consecutive adult patient colonoscopies during a 1-year period were retrospectively assessed in a single Australian tertiary endoscopy center. Adenoma detection quotient (ADQ) and SSA/P detection quotient (SSA/P-DQ) were defined as the division of ADR and SSA/P-DR by PDR, respectively. The primary outcome was the number of procedures to achieve a stable cumulative ADQ and SSA/P-DQ. Secondary outcomes included evaluation of ADQ and SSA/P-DQ in different subsets. Results:In total, 2,657 colonoscopies were performed by 15 endoscopists in 2016. The ADR, SSA/P-DR, and PDR found were 32.2, 6.7, and 47.3%, respectively. The ADQ and SSA/P-DQ values found were 0.68 and 0.14, respectively. After approximately 500 procedures, both ADQ and SSA/P-DQ became stable. Interclass correlation coefficient (ICC) for the prediction of ADR from ADQ was excellent for all endoscopists that performed >177 procedures in that year (ICC 0.84). Conclusions:ADQ and SSA/P-DQ values were consistent when over 500 procedures were analyzed. ADQ had an excellent correlation with ADR when >177 procedures per endoscopist were evaluated.
Project description:BACKGROUND AND AIM:Minimizing endoscopist exposure to bodily fluids is important for reducing the risk of infection transmission. This study investigated the patient-endoscopist vertical distance necessary to minimize an endoscopist's facial exposure to a patient's visible droplets during upper gastrointestinal endoscopy and the ability of a new device to prevent droplets from reaching the endoscopist's face. METHODS:A model was developed to simulate a patient experiencing a forceful cough during an upper gastrointestinal endoscopy with a model endoscopist. Fluorescent dye was expelled from the model patient's mouth towards the model endoscopist during simulated coughs; dye adhesion to the model endoscopist's face was evaluated using ultraviolet light. The simulation was repeated with the model patient positioned 70-100 cm above the floor, with and without a barrier to shield the patient's face. The accuracy of the cough simulation model and the relationship between patient-endoscopist vertical distance and endoscopist's facial exposure were evaluated. RESULTS:The flow dynamics of the cough simulation model were similar to that of an actual human cough. There was a significant inverse correlation between the patient-endoscopist vertical distance and the model endoscopist's facial exposure, with positive exposures decreasing from 87% at 70 cm to 0% at 100 cm (P < 0.001). The barrier device prevented facial exposure to droplets at all distances. CONCLUSIONS:We found that positioning the patient at least 100 cm below the top of the endoscopist's head or using a barrier device minimized the endoscopist's facial exposure to visible droplets during upper gastrointestinal endoscopy.
Project description:Importance:Histologic classification of colorectal polyps plays a critical role in screening for colorectal cancer and care of affected patients. An accurate and automated algorithm for the classification of colorectal polyps on digitized histopathologic slides could benefit practitioners and patients. Objective:To evaluate the performance and generalizability of a deep neural network for colorectal polyp classification on histopathologic slide images using a multi-institutional data set. Design, Setting, and Participants:This prognostic study used histopathologic slides collected from January 1, 2016, to June 31, 2016, from Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, with 326 slides used for training, 157 slides for an internal data set, and 25 for a validation set. For the external data set, 238 slides for 179 distinct patients were obtained from 24 institutions across 13 US states. Data analysis was performed from April 9 to November 23, 2019. Main Outcomes and Measures:Accuracy, sensitivity, and specificity of the model to classify 4 major colorectal polyp types: tubular adenoma, tubulovillous or villous adenoma, hyperplastic polyp, and sessile serrated adenoma. Performance was compared with that of local pathologists' at the point of care identified from corresponding pathology laboratories. Results:For the internal evaluation on the 157 slides with ground truth labels from 5 pathologists, the deep neural network had a mean accuracy of 93.5% (95% CI, 89.6%-97.4%) compared with local pathologists' accuracy of 91.4% (95% CI, 87.0%-95.8%). On the external test set of 238 slides with ground truth labels from 5 pathologists, the deep neural network achieved an accuracy of 87.0% (95% CI, 82.7%-91.3%), which was comparable with local pathologists' accuracy of 86.6% (95% CI, 82.3%-90.9%). Conclusions and Relevance:The findings suggest that this model may assist pathologists by improving the diagnostic efficiency, reproducibility, and accuracy of colorectal cancer screenings.
Project description:BACKGROUND:It is unknown whether narrow-band imaging (NBI) could be more effective than high-definition white-light endoscopy (HD-WLE) in detecting serrated lesions in patients with prior serrated lesions >?5?mm not completely fulfilling serrated polyposis syndrome (SPS) criteria. METHODS:We conducted a randomized, cross-over trial in consecutive patients with prior detection of at least one serrated polyp ?10?mm or???3 serrated polyps larger than 5?mm, both proximal to the sigmoid colon. Five experienced endoscopists performed same-day tandem colonoscopies, with the order being randomized 1:1 to NBI-HD-WLE or HD-WLE-NBI. All tandem colonoscopies were performed by the same endoscopist. RESULTS:We included 41 patients. Baseline characteristics were similar in the two cohorts: NBI-HD-WLE (n?=?21) and HD-WLE-NBI (n?=?20). No differences were observed in the serrated lesion detection rate of NBI versus HD-WLE: 47.4% versus 51.9% (OR 0.84, 95% CI: 0.37-1.91) for the first and second withdrawal, respectively. Equally, no differences were found in the polyp miss rate of NBI versus HD-WLE: 21.3% versus 26.1% (OR 0.77, 95% CI: 0.43-1.38). Follow-up colonoscopy in nine patients (22%) allowed them to be reclassified as having SPS. CONCLUSIONS:In patients with previous serrated lesions, the serrated lesion detection rate was similar with NBI and HD-WLE. A shorter surveillance colonoscopy interval increases the detection of missed serrated polyps and could change the diagnosis of SPS in approximately one in every five patients. TRIAL REGISTRATION:ClinicalTrials.gov NCT02406547, registered on April 2, 2015.
Project description:An automated image analysis system, e-Pathologist, was developed to improve the quality of colorectal biopsy diagnostics in routine pathology practice.The aim of the study was to evaluate the classification accuracy of the e-Pathologist image analysis software in the setting of routine pathology practice in two institutions.In total, 1328 colorectal tissue specimens were consecutively obtained from two hospitals (1077 tissues from Tokyo hospital, and 251 tissues from East hospital) and the stained specimen slides were anonymized and digitized. At least two experienced gastrointestinal pathologists evaluated each slide for pathological diagnosis. We compared the 3-tier classification results (carcinoma or suspicion of carcinoma, adenoma, and lastly negative for a neoplastic lesion) between the human pathologists and that of e-Pathologist.For the Tokyo hospital specimens, all carcinoma tissues were correctly classified (n=112), and 9.9% (80/810) of the adenoma tissues were incorrectly classified as negative. For the East hospital specimens, 0 out of the 51 adenoma tissues were incorrectly classified as negative while 9.3% (11/118) of the carcinoma tissues were incorrectly classified as either adenoma, or negative. For the Tokyo and East hospital datasets, the undetected rate of carcinoma, undetected rate of adenoma, and over-detected proportion were 0% and 9.3%, 9.9% and 0%, and 36.1% and 27.1%, respectively.This image analysis system requires some improvements; however, it has the potential to assist pathologists in quality improvement of routine pathological practice in the not too distant future.
Project description:Background and Aim:While adenoma detection rate (ADR) is an important quality metric for screening colonoscopy, it remains difficult to be accessed due to the lack of integrated endoscopy and pathology databases. Hence, the use of an adenoma-to-polyp detection rate quotient and polyp detection rate (PDR) has been proposed to predict ADR. This study aimed to examine the usefulness of estimated ADR across different colonic segments in two age groups for Shenzhen people in China. Methods:We retrospectively analyzed 7329 colonoscopy procedures performed by 12 endoscopists between January 2012 and February 2014. The PDR, actual ADR, and estimated ADR of the entire, proximal, and distal colon, and within each colonic segment, in two patient age groups: <50 and ?50?years, were calculated for each endoscopist. Results:The overall polyp and adenoma prevalence rates were 19.1 and 9.3%, respectively. The average age of adenoma-positive patients was significantly higher than that of adenoma-negative patients (54?±?12.6?years vs 42.9?±?13.2?years, respectively). A total of 1739 polyps were removed, among which 826 were adenomas. More adenomatous polyps were found in the proximal colon (60.4%, 341/565) than in the distal colon (40.9%, 472/1154). Overall, both actual and estimated ADR correlated strongly at the entire colon level and within most colonic segments, except for the cecum and rectum. In both age groups, these parameters correlated strongly within the traverse colon and descending colon. Conclusion:Caution should be exercised when predicting ADR within the sigmoid colon and rectum.
Project description:BACKGROUND:Diagnostic interpretations of melanocytic skin lesions vary widely among pathologists, yet the underlying reasons remain unclear. OBJECTIVE:Identify pathologist characteristics associated with rates of accuracy and reproducibility. METHODS:Pathologists independently interpreted the same set of biopsy specimens from melanocytic lesions on 2 occasions. Diagnoses were categorized into 1 of 5 classes according to the Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis system. Reproducibility was determined by pathologists' concordance of diagnoses across 2 occasions. Accuracy was defined by concordance with a consensus reference standard. Associations of pathologist characteristics with reproducibility and accuracy were assessed individually and in multivariable logistic regression models. RESULTS:Rates of diagnostic reproducibility and accuracy were highest among pathologists with board certification and/or fellowship training in dermatopathology and in those with 5 or more years of experience. In addition, accuracy was high among pathologists with a higher proportion of melanocytic lesions in their caseload composition and higher volume of melanocytic lesions. LIMITATIONS:Data gathered in a test set situation by using a classification tool not currently in clinical use. CONCLUSION:Diagnoses are more accurate among pathologists with specialty training and those with more experience interpreting melanocytic lesions. These findings support the practice of referring difficult cases to more experienced pathologists to improve diagnostic accuracy, although the impact of these referrals on patient outcomes requires additional research.
Project description:Background and objectives:The UK bowel cancer screening programme (BCSP) has been established for the early detection of colorectal cancer offering colonoscopy to patients screened positive by faecal occult blood tests. In this multisite, prospective, randomised controlled trial, we aimed to compare the performance of Standard Definition Olympus Lucera (SD-OL) with Scope Guide and the High Definition Pentax HiLine (HD-PHL). Patients and methods:Subjects undergoing a colonoscopy as part of the UK National BCSP at four UK sites were randomised to an endoscopy list run using either SD-OL or HD-PHL. Primary endpoints were polyp and adenoma detection rate (PDR and ADR, respectively) as well as polyp size, morphology and histology characteristics. Results:262 subjects (168 males, mean age 66.3±4.3 years) were colonoscoped (133 patients with HD-PHL while 129 with SD-OL). PDR and ADR were comparable within the two optical systems. The HD-PHL group resulted in a PDR 55.6% and ADR 43.6%; the SD-OL group had PDR 56.6% and ADR 45.7%. HD-PHL was significantly superior to SD-OL in detection of flat adenomas (18.6% vs 5.2%, p<0.001), but not detection of pedunculated or sessile polyps. Patient comfort, use of sedation and endoscopist perception of procedural difficulty resulted similar despite the use of Scope Guide with SD-OL. Conclusion:PDR and ADR were not significantly different between devices. The high-resolution colonoscopy system HD-PHL may improve polyp detection as compared with standard resolution technology in detecting flat adenomas. This advantage may have clinically significant implications for missed lesion rates and post-colonoscopy interval colorectal cancer rates.
Project description:Adenoma detection rate (ADR) has been established as a quality indicator for screening colonoscopy. Because ADR is cumbersome to obtain in routine practice, polyp detection rate (PDR), polypectomy rate (PR) and adenoma-to-polyp-detection-rate-ratio (APDRR) have been proposed to estimate ADR. This study aimed to evaluate APDRR in order to estimate ADR (ADRest) in different settings.Average risk screening and surveillance colonoscopies from a community-based private practice and a tertiary academic hospital setting were retrospectively evaluated. APDRR was calculated as averaged group APDRR for all study procedures (APDRR) and for the first half of study procedures of each gastroenterologist (APDRRag) or individually for each gastroenterologist on the basis of his or her first 25, 50 and 100 colonoscopies (APDRRind). ADRest was determined from PDR by using APDRR, APDRRag, and APDRRind, respectively.A total of 2717 individuals were analyzed. Using APDRR, significant correlations between ADR and ADRest were observed for the entire (0.944, p < 0.001), proximal (0.854, p < 0.001), and distal (0.977, p < 0.001) colon. These correlations were lost when APDRRag was used to estimate each gastroenterologist's ADR for the second half of his or her included colonoscopies. However, ADR and ADRest correlated significantly with a root-mean-square-error of 6.8% and 5.8% when APDRRind on the basis of each gastroenterologist's first 50 and 100 colonoscopies was used for subsequent colonoscopies.ADR for subsequent colonoscopies of an individual endoscopist can be reliably estimated from PDR by using an individually calculated APDRR. Prospective studies are needed to verify this promising approach in different practice settings.