Patient safety in anatomic pathology: measuring discrepancy frequencies and causes

Cytologic-Histologic Correlation Practices for Nongynecologic Cytology Specimens: A Survey by the College of American Pathologists Cytopathology Committee

CONTEXT.—

Cytologic-histologic correlation (CHC) is a Clinical Laboratory Improvement Amendments-mandated requirement for gynecologic cytology, but no similar requirement exists for nongynecologic cytology. This study presents the findings from a College of American Pathologists survey of nongynecologic cytology practice patterns.

OBJECTIVE.—

To survey the current CHC practices for nongynecologic cytology.

DESIGN.—

Data were analyzed from a survey developed by the committee and distributed to participants in the Nongynecologic Cytopathology Education Program mailing.

RESULTS.—

Adoption of CHC for nongynecologic cytology cases is worldwide, with 88.5% of institutions performing CHC on these specimens, a substantial increase from previous years. Performance of CHC varied by institution type, with clinic or regional/local independent laboratories and national/corporate laboratories performing CHC significantly less frequently than hospitals, university hospitals/academic medical centers, and Veterans Administration/Department of Defense hospital institutions. Most CHC was performed concurrently in real time, when the corresponding surgical specimen was reviewed. Selection for real-time concurrent CHC was by the interpreting pathologist, the pathologist diagnosing the surgical biopsy sample or cytopathology case, or both. Sampling was by far the most common reason for discordance. A 2-step difference was the most frequent threshold for discordance between cytology and surgical specimens, but this criterion varied among institutions, with no majority definition. The positive predictive value of a positive cytology finding was calculated rarely in North American institutions but was calculated more frequently in international institutions.

CONCLUSIONS.—

CHC practices for nongynecologic cytopathology mirror those found for CHC of gynecologic cytopathology.

Cytology-histology correlation of cervical Papanicolaou smears and biopsies performed at a single institution compared to those performed at different institutions

OBJECTIVE

Cytology-histology correlation (CHC) is the gold standard of quality assurance in cytology laboratories to ensure appropriate patient treatment, and as an educational tool for cytology laboratory personnel. If cervical Pap smears (CPs) and cervical biopsies (CBs) are performed at different institutions, these benefits may be lost.

METHODS

All CBs performed at our institution from 1 January 2019 to 31 December 2019 with adequate CPs performed in the 6 months prior to the CB were included in this retrospective review. We compared the CHC for CPs and CBs performed at a single institution to the CHC for CPs and CBs performed at different institutions, with a focus on the proportion of overcalls on CPs, as those are the most challenging discrepant CHC to manage clinically. We used the American Society of Cytology guidelines for our discrepancy assessment grid. A Chi-squared test was used to compare the proportions of the populations. The P-value was set at < 0.05.

RESULTS

Of the 305 CBs in our study population, 69 had a CP performed at our institution and 236 had a CP performed at an outside institution. The CHC for CBs and CPs performed at a single institution showed statistically significantly less disagreement than the CHC for those performed at different institutions (P < 0.05). Further, CBs and CPs performed at a single institution had statistically significantly fewer overcalls than CBs and CPs performed at different institutions (P < 0.05).

CONCLUSION

This study further supports the use of CHC, and in light of our findings we recommend that a patient's CPs and CBs are performed at the same institution. If performing a CP and CB at the same institution is not feasible, a prospective consultation review of the CP by the institution performing the CB should be strongly considered. Further study, including an evaluation of the reason for the discrepancy in discordant cases may better elucidate the reasons for better CHC agreement when CP and CB are performed at the same institution.

Error Reduction and Diagnostic Concordance in Breast Pathology

Errors in anatomic pathology can result in patients receiving inappropriate treatment and poor patient outcomes. Policies and procedures are necessary to decrease error and improve diagnostic concordance. Breast pathology may be more prone to diagnostic errors than other surgical pathology subspecialties due to inherit borderline diagnostic categories such as atypical ductal hyperplasia and low-grade ductal carcinoma in situ. Mandatory secondary review of internal and outside referral cases before treatment is effective in reducing diagnostic errors and improving concordance. Assessment of error through amendment/addendum tracking, implementing an incident reporting system, and multidisciplinary tumor boards can establish procedures to prevent future error.

Anatomy of a Cyberattack: Part 4: Quality Assurance and Error Reduction, Billing and Compliance, Transition to Uptime

OBJECTIVES

Our institution was the victim of a cyberattack that necessitated use of manual laboratory systems for more than 25 days. These manual processes had to be created not only to enable us to process our case volume without bottlenecks but also to maintain patient safety and allow for billing.

METHODS

Our laboratory needed to create a safe reporting process to ensure ongoing patient safety and error reduction during the downtime. Additionally, we needed to ensure the ability to bill for performed tests in some areas of the lab and maintain compliance with regulatory policies.

RESULTS

Amendment rates in our system were higher than before the attack, but no patient harm was observed. Intraoperative assessments declined, but high-acuity cases continued with a discrepancy rate comparable with the normal state. Many hours and resources (human and otherwise) were necessary to reconcile the work done to bill for services, but we were able to capture revenue through careful planning.

CONCLUSIONS

This article records the challenges we faced and the successes we achieved in maintaining compliance and a low error rate in the face of manual processes, the steps necessary to bring the cases into the newly restored electronic health record, and how we billed for the services we rendered.

Diagnostic concordance among pathologists interpreting breast core biopsies on secondary review over a 1-year period at an Australian tertiary hospital

This study provides data on the diagnostic concordance between initial and review diagnoses of all breast core biopsy cases at a single tertiary hospital in Western Australia over a 1-year period. A retrospective review of all breast core biopsy cases between January 1 and December 31, 2016, was carried out at PathWest, Fiona Stanley Hospital in Perth, Western Australia. Each biopsy is reported by a single pathologist and then reviewed within 1 week by a panel of intradepartmental subspecialist breast pathologists, who either agree with the original diagnosis, have a minor discordant diagnosis, or a major discordant diagnosis. Records for 2036 core biopsies were available between January 1 and December 31, 2016. Of these, 56.0% (n = 1141) were classified as benign, 34.3% (n = 699) as malignant, 7.2% (n = 147) as indeterminate, 2.3% (n = 46) as nondiagnostic, and 0.1% (n = 3) as suspicious for malignancy. In 99.1% (n = 2018) of cases, there was agreement between initial and review diagnoses. In total, 0.9% (n = 18) were disagreements: 0.49% (n = 10) were major discordant disagreements and 0.39% (n = 8) were minor discordant disagreements. All cases of major discordant disagreements would have resulted in significant changes to clinical management. This study demonstrates that an Australian institution is providing a high-quality pathology service with a low error rate between initial and review diagnoses of breast core biopsies. It reinforces the importance of secondary review of biopsies in a timely fashion for detecting potentially serious misdiagnoses that could lead to inappropriate management.

Rapid Validation of Whole-Slide Imaging for Primary Histopathology Diagnosis

OBJECTIVES

The ongoing global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic necessitates adaptations in the practice of surgical pathology at scale. Primary diagnosis by whole-slide imaging (WSI) is a key component that would aid departments in providing uninterrupted histopathology diagnosis and maintaining revenue streams from disruption. We sought to perform rapid validation of the use of WSI in primary diagnosis meeting recommendations of the College of American Pathologists guidelines.

METHODS

Glass slides from clinically reported cases from 5 participating pathologists with a preset washout period were digitally scanned and reviewed in settings identical to typical reporting. Cases were classified as concordant or with minor or major disagreement with the original diagnosis. Randomized subsampling was performed, and mean concordance rates were calculated.

RESULTS

In total, 171 cases were included and distributed equally among participants. For the group as a whole, the mean concordance rate in sampled cases (n = 90) was 83.6% counting all discrepancies and 94.6% counting only major disagreements. The mean pathologist concordance rate in sampled cases (n = 18) ranged from 90.49% to 97%.

CONCLUSIONS

We describe a novel double-blinded method for rapid validation of WSI for primary diagnosis. Our findings highlight the occurrence of a range of diagnostic reproducibility when deploying digital methods.

Diagnostic discrepancy in second opinion reviews of primary epithelial neoplasms involving salivary gland: An 11-year experience from a tertiary referral center focusing on useful pathologic approaches and potential clinical impacts

AIMS

In the era of precision medicine, accurate pathologic diagnoses are crucial for appropriate management.

METHODS

We herein described the histologic features and clinical impacts of 66 salivary gland epithelial neoplasms in which the diagnosis was altered after expert review.

RESULTS

The most common revised diagnosis was that of salivary duct carcinoma (SDC, n = 12), adenoid cystic carcinoma (n = 12), and myoepithelial carcinoma (n = 10). The most common initial diagnosis was mucoepidermoid carcinoma (n = 19) with SDC being the most common revised diagnosis (7/19). Thirteen salivary gland carcinomas were initially diagnosed as benign entities, whereas five benign tumors were initially interpreted as carcinoma. The change in diagnosis was considered to be clinically significant in 65 (97%) cases.

CONCLUSIONS

Given their rarity, salivary gland neoplasms are prone to diagnostic inaccuracy and discrepancy. A constellation of histologic features and ancillary studies are useful in reaching the correct diagnosis, which can have significant clinical impacts.

Searching Images for Consensus: Can AI Remove Observer Variability in Pathology?

One of the major obstacles in reaching diagnostic consensus is observer variability. With the recent success of artificial intelligence, particularly the deep networks, the question emerges as to whether the fundamental challenge of diagnostic imaging can now be resolved. This article briefly reviews the problem and how eventually both supervised and unsupervised AI technologies could help to overcome it.

Erroneous diagnosis of primary fibrosarcoma of the breast: The value of the multidisciplinary breast team approach

Diagnostic errors occur in the preanalytic, analytic, and postanalytic phases of specimen processing. Correlating clinical and imaging information with gross and microscopic findings is crucial to limit errors and unnecessary treatment. Herein, we report the case of a 54-year-old woman who presented with left breast bloody nipple discharge and subsequently underwent central duct excision. Pathology revealed a high-grade sarcoma. The patient presented to our institution for further management. Upon secondary pathology review and DNA fingerprinting analysis, the correct interpretation was rendered. Our case demonstrates the importance of clinical correlation and review of pathology slides prior to definitive therapy.

Verification and Validation of Digital Pathology (Whole Slide Imaging) for Primary Histopathological Diagnosis: All Wales Experience

Aims:

The study is aimed to verify Aperio AT2 scanner for reporting on the digital pathology platform (DP) and to validate the cohort of pathologists in the interpretation of DP for routine diagnostic histopathological services in Wales, United Kingdom.

Materials, Methods and Results:

This was a large multicenter study involving seven hospitals across Wales and unique with 22 (largest number) pathologists participating. 7491 slides from 3001 cases were scanned on Leica Aperio AT2 scanner and reported on digital workstations with Leica software of e-slide manager. A senior pathology fellow compared DP reports with authorized reports on glass slide (GS). A panel of expert pathologists reviewed the discrepant cases under multiheader microscope to establish ground truth. 2745 out of 3001 (91%) cases showed complete concordance between DP and GS reports. Two hundred and fifty-six cases showed discrepancies in diagnosis, of which 170 (5.6%) were deemed of no clinical significance by the review panel. There were 86 (2.9%) clinically significant discrepancies in the diagnosis between DP and GS. The concordance was raised to 97.1% after discounting clinically insignificant discrepancies. Ground truth lay with DP in 28 out of 86 clinically significant discrepancies and with GS in 58 cases. Sensitivity of DP was 98.07% (confidence interval [CI] 97.57–98.56%); for GS was 99.07% (CI 98.72–99.41%).

Conclusions:

We concluded that Leica Aperio AT2 scanner produces adequate quality of images for routine histopathologic diagnosis. Pathologists were able to diagnose in DP with good concordance as with GS.

Strengths and Limitations of this Study:

Strengths of this study – This was a prospective blind study. Different pathologists reported digital and glass arms at different times giving an ambience of real-time reporting. There was standardized use of software and hardware across Wales. A strong managerial support from efficiency through the technology group was a key factor for the implementation of the study.

Limitations:

This study did not include Cytopathology and in situ hybridization slides. Difficulty in achieving surgical pathology practise standardization across the whole country contributed to intra-observer variations.

Remote Reporting from Home for Primary Diagnosis in Surgical Pathology: A Tertiary Oncology Center Experience during the COVID-19 Pandemic

BACKGROUND

The COVID-19 pandemic accelerated the widespread adoption of digital pathology (DP) for primary diagnosis in surgical pathology. This paradigm shift is likely to influence how we function routinely in the postpandemic era. We present learnings from early adoption of DP for a live digital sign-out from home in a risk-mitigated environment.

MATERIALS AND METHODS

We aimed to validate DP for remote reporting from home in a real-time environment and evaluate the parameters influencing the efficiency of a digital workflow. Eighteen pathologists prospectively validated DP for remote use on 567 biopsy cases including 616 individual parts from 7 subspecialties over a duration from March 21, 2020, to June 30, 2020. The slides were digitized using Roche Ventana DP200 whole-slide scanner and reported from respective homes in a risk-mitigated environment.

RESULTS

Following re-review of glass slides, there was no major discordance and 1.2% (n = 7/567) minor discordance. The deferral rate was 4.5%. All pathologists reported from their respective homes from laptops with an average network speed of 20 megabits per second.

CONCLUSION

We successfully validated and adopted a digital workflow for remote reporting with available resources and were able to provide our patients, an undisrupted access to subspecialty expertise during these unprecedented times.

Validation of a digital pathology system including remote review during the COVID-19 pandemic

Remote digital pathology allows healthcare systems to maintain pathology operations during public health emergencies. Existing Clinical Laboratory Improvement Amendments regulations require pathologists to electronically verify patient reports from a certified facility. During the 2019 pandemic of COVID-19 disease, caused by the SAR-CoV-2 virus, this requirement potentially exposes pathologists, their colleagues, and household members to the risk of becoming infected. Relaxation of government enforcement of this regulation allows pathologists to review and report pathology specimens from a remote, non-CLIA certified facility. The availability of digital pathology systems can facilitate remote microscopic diagnosis, although formal comprehensive (case-based) validation of remote digital diagnosis has not been reported. All glass slides representing routine clinical signout workload in surgical pathology subspecialties at Memorial Sloan Kettering Cancer Center were scanned on an Aperio GT450 at ×40 equivalent resolution (0.26 µm/pixel). Twelve pathologists from nine surgical pathology subspecialties remotely reviewed and reported complete pathology cases using a digital pathology system from a non-CLIA certified facility through a secure connection. Whole slide images were integrated to and launched within the laboratory information system to a custom vendor-agnostic, whole slide image viewer. Remote signouts utilized consumer-grade computers and monitors (monitor size, 13.3-42 in.; resolution, 1280 × 800-3840 × 2160 pixels) connecting to an institution clinical workstation via secure virtual private network. Pathologists subsequently reviewed all corresponding glass slides using a light microscope within the CLIA-certified department. Intraobserver concordance metrics included reporting elements of top-line diagnosis, margin status, lymphovascular and/or perineural invasion, pathology stage, and ancillary testing. The median whole slide image file size was 1.3 GB; scan time/slide averaged 90 s; and scanned tissue area averaged 612 mm². Signout sessions included a total of 108 cases, comprised of 254 individual parts and 1196 slides. Major diagnostic equivalency was 100% between digital and glass slide diagnoses; and overall concordance was 98.8% (251/254). This study reports validation of primary diagnostic review and reporting of complete pathology cases from a remote site during a public health emergency. Our experience shows high (100%) intraobserver digital to glass slide major diagnostic concordance when reporting from a remote site. This randomized, prospective study successfully validated remote use of a digital pathology system including operational feasibility supporting remote review and reporting of pathology specimens, and evaluation of remote access performance and usability for remote signout.

Assessment of Interlaboratory Variation in the Interpretation of Genomic Test Results in Patients With Epilepsy

IMPORTANCE

Discordance in the interpretations of genetic test results has occurred with the increased number of laboratories that are performing testing. Differences in diagnostic interpretations may have implications for the treatment of patients.

OBJECTIVE

To assess the interlaboratory variation in the interpretations of genetic test results with potential therapeutic implications.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study, 70 genes that are commonly tested in patients with epilepsy were examined to identify 22 676 genetic variants from an unknown number of patients using the ClinVar public database of clinically annotated variants. Variant annotations submitted to ClinVar (data set version 2019-05) between November 16, 2012, and May 3, 2019, were included in the analysis. Conflicting interpretations of the genetic variants associated with epilepsy were analyzed for clinically substantial discrepancies between May 7 and June 29, 2019. Variants were examined only if they had been interpreted by 2 or more clinical laboratories. A variant with a clinically substantial difference in interpretation was defined as a variant that crossed the threshold between a likely pathogenic variant and a variant of uncertain significance.

MAIN OUTCOMES AND MEASURES

The frequency and types of variant interpretation conflicts were analyzed when a conflict was identified.

RESULTS

A total of 6292 of 22 676 variants related to epilepsy (27.7%) were interpreted by 2 or more clinical laboratories. Many variants (3307 of 6292 [52.6%]) had interpretations that were fully concordant. However, 2985 variants (47.4%) had conflicting interpretations. A clinically substantial conflict was identified in 201 of 6292 variants (3.2%). Furthermore, 117 of 201 variants (58.2%) with differences in interpretation occurred in genes with therapeutic implications.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, most interpretations of genetic variants associated with epilepsy were concordant among laboratories, but more than half of the variants with conflicting interpretations occurred in genes that have therapeutic implications. It would be helpful for genetic laboratories to report known diagnostic discordance with other clinical laboratories.

Whole slide imaging equivalency and efficiency study: experience at a large academic center

Whole slide imaging is Food and Drug Administration-approved for primary diagnosis in the United States of America; however, relatively few pathology departments in the country have fully implemented an enterprise wide digital pathology system enabled for primary diagnosis. Digital pathology has significant potential to transform pathology practice with several published studies documenting some level of diagnostic equivalence between digital and conventional systems. However, whole slide imaging also has significant potential to disrupt pathology practice, due to the differences in efficiency of manipulating digital images vis-à-vis glass slides, and studies on the efficiency of actual digital pathology workload are lacking. Our randomized, equivalency and efficiency study aimed to replicate clinical workflow, comparing conventional microscopy to a complete digital pathology signout using whole slide images, evaluating the equivalency and efficiency of glass slide to whole slide image reporting, reflective of true pathology practice workloads in the clinical setting. All glass slides representing an entire day's routine clinical signout workload for six different anatomic pathology subspecialties at Memorial Sloan Kettering Cancer Center were scanned on Leica Aperio AT2 at ×40 (0.25 µm/pixel). Integration of whole slide images for each accessioned case is through an interface between the Leica eSlide manager database and the laboratory information system, Cerner CoPathPlus. Pathologists utilized a standard institution computer workstation and viewed whole slide images through an internally developed, vendor agnostic whole slide image viewer, named the "MSK Slide Viewer". Subspecialized pathologists first reported on glass slides from surgical pathology cases using routine clinical workflow. Glass slides were de-identified, scanned, and re-accessioned in the laboratory information system test environment. After a washout period of 13 weeks, pathologists reported the same clinical workload using whole slide image integrated within the laboratory information system. Intraobserver equivalency metrics included top-line diagnosis, margin status, lymphovascular and/or perineural invasion, pathology stage, and the need to order ancillary testing (i.e., recuts, immunohistochemistry). Turnaround time (efficiency) evaluation was defined by the start of each case when opened in the laboratory information system and when the case was completed for that day (i.e., case sent to signout queue or pending ancillary studies). Eight pathologists participated from the following subspecialties: bone and soft tissue, genitourinary, gastrointestinal, breast, gynecologic, and dermatopathology. Glass slides signouts comprised of 204 cases, encompassing 2091 glass slides; and digital signouts comprised of 199 cases, encompassing 2073 whole slide images. The median whole slide image file size was 1.54 GB; scan time/slide, 6 min 24 s; and scan area 32.1 × 18.52 mm. Overall diagnostic equivalency (e.g., top-line diagnosis) was 99.3% between digital and glass slide signout; however, signout using whole slide images showed a median overall 19% decrease in efficiency per case. No significant difference by reader, subspecialty, or specimen type was identified. Our experience is the most comprehensive study to date and shows high intraobserver whole slide image to glass slide equivalence in reporting of true clinical workflows and workloads. Efficiency needs to improve for digital pathology to gain more traction among pathologists.

Histological coherent Raman imaging: a prognostic review

Histopathology plays a central role in diagnosis of many diseases including solid cancers. Efforts are underway to transform this subjective art to an objective and quantitative science. Coherent Raman imaging (CRI), a label-free imaging modality with sub-cellular spatial resolution and molecule-specific contrast possesses characteristics which could support the qualitative-to-quantitative transition of histopathology. In this work we briefly survey major themes related to modernization of histopathology, review applications of CRI to histopathology and, finally, discuss potential roles for CRI in the transformation of histopathology that is already underway.

The cost-saving effect of centralized histological reviews with soft tissue and visceral sarcomas, GIST, and desmoid tumors: The experiences of the pathologists of the French Sarcoma Group

OBJECTIVE

This study examined the types of discordance occurring in the diagnosis of soft tissue and visceral sarcomas, gastrointestinal stromal tumors (GIST), and desmoid tumors, as well as the economic impact of diagnostic discrepancies.

METHODS

We carried out a retrospective, multicenter analysis using prospectively implemented databases performed on a cohort of patients within the French RRePS network in 2010. Diagnoses were deemed to be discordant based on the 2013 World Health Organization (WHO) classification. Predictive factors of discordant diagnoses were explored. A decision tree was used to assess the expected costs of two strategies of disease management: one based on revised diagnoses after centralized histological review (option 1), the other on diagnoses without centralized review (option 2). Both were defined based on the patient and the disease characteristics, according to national or international guidelines. The time horizon was 12 months and the perspective of the French National Health Insurance (NHI) was retained. Costs were expressed in Euros for 2013. Sensitivity analyses were performed using low and high scenarios that included ± 20% estimates for cost.

RESULTS

A total of 2,425 patients were included. Three hundred forty-one patients (14%) had received discordant diagnoses. These discordances were determined to mainly be benign tumors diagnosed as sarcomas (n = 124), or non-sarcoma malignant tumors diagnosed as sarcomas (n = 77). The probability of discordance was higher for a final diagnosis of desmoid tumors when compared to liposarcomas (odds ratio = 5.1; 95%CI [2.6-10.4]). The expected costs per patient for the base-case analysis (low- and high-case scenarios) amounted to €8,791 (€7,033 and €10,549, respectively) for option 1 and €8,904 (€7,057 and €10,750, respectively) for option 2.

CONCLUSIONS

Our findings highlight misdiagnoses of sarcomas, which were found to most often be confused with benign tumors. Centralized histological reviews are likely to provide cost-savings for the French NHI.

Whole Slide Imaging Versus Microscopy for Primary Diagnosis in Surgical Pathology: A Multicenter Blinded Randomized Noninferiority Study of 1992 Cases (Pivotal Study)

Most prior studies of primary diagnosis in surgical pathology using whole slide imaging (WSI) versus microscopy have focused on specific organ systems or included relatively few cases. The objective of this study was to demonstrate that WSI is noninferior to microscopy for primary diagnosis in surgical pathology. A blinded randomized noninferiority study was conducted across the entire range of surgical pathology cases (biopsies and resections, including hematoxylin and eosin, immunohistochemistry, and special stains) from 4 institutions using the original sign-out diagnosis (baseline diagnosis) as the reference standard. Cases were scanned, converted to WSI and randomized. Sixteen pathologists interpreted cases by microscopy or WSI, followed by a wash-out period of ≥4 weeks, after which cases were read by the same observers using the other modality. Major discordances were identified by an adjudication panel, and the differences between major discordance rates for both microscopy (against the reference standard) and WSI (against the reference standard) were calculated. A total of 1992 cases were included, resulting in 15,925 reads. The major discordance rate with the reference standard diagnosis was 4.9% for WSI and 4.6% for microscopy. The difference between major discordance rates for microscopy and WSI was 0.4% (95% confidence interval, -0.30% to 1.01%). The difference in major discordance rates for WSI and microscopy was highest in endocrine pathology (1.8%), neoplastic kidney pathology (1.5%), urinary bladder pathology (1.3%), and gynecologic pathology (1.2%). Detailed analysis of these cases revealed no instances where interpretation by WSI was consistently inaccurate compared with microscopy for multiple observers. We conclude that WSI is noninferior to microscopy for primary diagnosis in surgical pathology, including biopsies and resections stained with hematoxylin and eosin, immunohistochemistry and special stains. This conclusion is valid across a wide variety of organ systems and specimen types.

Investigation of pathology malpractice claims in China from 2002-2015

OBJECTIVE

To examine pathology-related medical claims in China and identify the most common errors to result in such claims.

METHOD

A retrospective analysis was performed of 71 forensic evaluation reports carried out in two Chinese institutes of forensic medicine between 2002 and 2015 due to suspicion of medical malpractice. The judicial outcomes of each case were also reviewed when available.

RESULTS

Of 71 cases, 54 cases had judicial outcomes. The most frequently claimed events were false-negative diagnoses of skin cancer, invasive ductal carcinoma of the breast, and osteosarcoma; and false positive diagnoses of uterine cervical squamous cell carcinoma, gastric carcinoma, and soft tissue carcinoma. The most common cause of error (82%, 56 of 68) was pathological misinterpretation. Plaintiffs in most cases (89%, 48 of 54) received compensation.

CONCLUSION

Our data are in agreement with other findings regarding the most frequent medical malpractice allegations related to pathology. Addressing the issues at the root of these claims would lead to a decline in the number of medical errors. Quality assurance programs and good pathologist-clinician communication may decrease the risk of litigation.

Specimen Identification Errors in Breast Biopsies: Age Matters. Report of Two Near-Miss Events and Review of the Literature

The consequences of patient identification errors due to specimen mislabeling can be deleterious. We describe two near-miss events involving mislabeled breast specimens from two patients who sought treatment at our institution. In both cases, microscopic review of the slides identified inconsistencies between the histologic findings and patient age, unveiling specimen identification errors. By correlating the clinical information with the microscopic findings, we identified mistakes that had occurred at the time of specimen accessioning at the original laboratories. In both cases, thanks to a timely reassignment of the specimens, the patients suffered no harm. These cases highlight the importance of routine clinical and pathologic correlation as a critical component of quality assurance and patient safety. A review of possible specimen identification errors in the anatomic pathology setting is presented.

Estimate of false-positive breast cancer diagnoses from accuracy studies: a systematic review

Background

False-positive histological diagnoses have the same consequences of overdiagnosis in terms of unnecessary treatment. The aim of this systematic review is to assess their frequency at needle core biopsy (CB) and/or surgical excision of the breast.

Methods

PubMed, Embase, Cochrane Library were systematically searched up to 30 October 2015. Eligibility criteria: cross-sectional studies assessing diagnostic accuracy of CB compared with surgical excision; studies assessing reproducibility of pathologists reading the same slides. Outcomes: false-positive rates; Misclassification of Benign as Malignant (MBM) histological diagnosis; K statistic. Independent reviewers extracted data and assessed quality using an adapted QUADAS-2 tool.

Results

Sixteen studies assessed CB false-positive rates. In 10 studies (41 989 screen-detected lesions), the range of false-positive rates was 0%–7.1%. Twenty-seven studies assessed pathologists' reproducibility. Studies with consecutive, random or stratified samples of all the specimens: at CB the MBM range was 0.25%–2.4% (K values 0.83–0.98); at surgical excision, it was 0.67%–1.2% (K values 0.86–0.94). Studies with enriched samples: the MBM range was 1.4%–6.2% (K values 0.57–0.86). Studies of cases selected for second opinion: the MBM range was 0.29%–12.2% (K values 0.48 and 0.50).

Conclusions

High heterogeneity of the included studies precluded formal pooling estimates. When considering studies of higher sample size or methodological quality, false-positive rates and MBM are around 1%. The impact of false-positive histological diagnoses of breast cancer on unnecessary treatment, as well as that of overdiagnosis, is not negligible and is of importance in clinical practice.

A multisite validation of whole slide imaging for primary diagnosis using standardized data collection and analysis

Context:

Text-based reporting and manual arbitration for whole slide imaging (WSI) validation studies are labor intensive and do not allow for consistent, scalable, and repeatable data collection or analysis.

Objective:

The objective of this study was to establish a method of data capture and analysis using standardized codified checklists and predetermined synoptic discordance tables and to use these methods in a pilot multisite validation study.

Methods and Study Design:

Fifteen case report form checklists were generated from the College of American Pathology cancer protocols. Prior to data collection, all hypothetical pairwise comparisons were generated, and a level of harm was determined for each possible discordance. Four sites with four pathologists each generated 264 independent reads of 33 cases. Preestablished discordance tables were applied to determine site by site and pooled accuracy, intrareader/intramodality, and interreader intramodality error rates.

Results:

Over 10,000 hypothetical pairwise comparisons were evaluated and assigned harm in discordance tables. The average difference in error rates between WSI and glass, as compared to ground truth, was 0.75% with a lower bound of 3.23% (95% confidence interval). Major discordances occurred on challenging cases, regardless of modality. The average inter-reader agreement across sites for glass was 76.5% (weighted kappa of 0.68) and for digital it was 79.1% (weighted kappa of 0.72).

Conclusion:

These results demonstrate the feasibility and utility of employing standardized synoptic checklists and predetermined discordance tables to gather consistent, comprehensive diagnostic data for WSI validation studies. This method of data capture and analysis can be applied in large-scale multisite WSI validations.

Patient Safety Curriculum for Anatomic Pathology Trainees: Recommendations Based on Institutional Experience

Because of the unique systems and skills involved in patient care by the pathologist, it is challenging to design and implement relevant training in patient safety for pathology trainees. We propose a patient safety curriculum for anatomic pathology (AP) residents based on our institutional experience. The Hospital of the University of the Pennsylvania employs a self-reporting safety database. The occurrences from July 2013 to June 2015 recorded in this system that involved the division of AP were reviewed and cataloged as preanalytic, analytic, and postanalytic. The distribution of these occurrences was then used to create a framework for curriculum development in AP. We identified areas in which trainees are involved in the identification and prevention of common patient safety errors that occur in our AP department. Using these data-proven target areas, and employing current Accreditation Council for Graduate Medical Education recommendations and patient safety literature, a strategy for delivering relevant patient safety training is proposed. Teaching patient safety to pathology trainees is a challenging, yet necessary, component of AP training programs. By analyzing the patient safety errors that occur in the AP department, relevant and actionable training can be developed. This provides quality professional development and improves overall performance as trainees are integrated into laboratory systems.

Interpretive Diagnostic Error Reduction in Surgical Pathology and Cytology: Guideline From the College of American Pathologists Pathology and Laboratory Quality Center and the Association of Directors of Anatomic and Surgical Pathology

CONTEXT

Additional reviews of diagnostic surgical and cytology cases have been shown to detect diagnostic discrepancies.

OBJECTIVE

To develop, through a systematic review of the literature, recommendations for the review of pathology cases to detect or prevent interpretive diagnostic errors.

DESIGN

The College of American Pathologists Pathology and Laboratory Quality Center in association with the Association of Directors of Anatomic and Surgical Pathology convened an expert panel to develop an evidence-based guideline to help define the role of case reviews in surgical pathology and cytology. A literature search was conducted to gather data on the review of cases in surgical pathology and cytology.

RESULTS

The panel drafted 5 recommendations, with strong agreement from open comment period participants ranging from 87% to 93%. The recommendations are: (1) anatomic pathologists should develop procedures for the review of selected pathology cases to detect disagreements and potential interpretive errors; (2) anatomic pathologists should perform case reviews in a timely manner to avoid having a negative impact on patient care; (3) anatomic pathologists should have documented case review procedures that are relevant to their practice setting; (4) anatomic pathologists should continuously monitor and document the results of case reviews; and (5) if pathology case reviews show poor agreement within a defined case type, anatomic pathologists should take steps to improve agreement.

CONCLUSIONS

Evidence exists that case reviews detect errors; therefore, the expert panel recommends that anatomic pathologists develop procedures for the review of pathology cases to detect disagreements and potential interpretive errors, in order to improve the quality of patient care.

Digital slide viewing for primary reporting in gastrointestinal pathology: a validation study

Despite the increasing availability of digital slide viewing, and numerous advantages associated with its application, a lack of quality validation studies is amongst the reasons for poor uptake in routine practice. This study evaluated primary digital pathology reporting in the setting of routine subspecialist gastrointestinal pathology, commonplace in most tissue pathology laboratories and representing one of the highest volume specialties in most laboratories. Individual digital and glass slide diagnoses were compared amongst three pathologists reporting in a gastrointestinal subspecialty team, in a prospective series of 100 consecutive diagnostic cases from routine practice in a large teaching hospital laboratory. The study included a washout period of at least 6 months. Discordant diagnoses were classified, and the study evaluated against recent College of American Pathologists (CAP) recommendations for evaluating digital pathology systems for diagnostic use. The study design met all 12 of the CAP recommendations. The 100 study cases generated 300 pairs of diagnoses, comprising 100 glass slide diagnoses and 100 digital diagnoses from each of the three study pathologists. 286 of 300 pairs of diagnoses were concordant, representing intraobserver concordance of 95.3 %, broadly comparable to rates previously published in this field. In ten of the 14 discordant pairs, the glass slide diagnosis was favoured; in four cases, the digital diagnosis was favoured, but importantly, the 14 discordant intraobserver diagnoses were considered to be of minor clinical significance. Interobserver, or viewing modality independent, concordance was found in 94 of the total of 100 study cases, providing a comparable baseline discordance rate expected in any second viewing of pathology material. These overall results support the safe use of digital pathology in primary diagnostic reporting in this setting.

Positive Association of Fibroadenomatoid Change with HER2-Negative Invasive Breast Cancer: A Co-Occurrence Study

Background

Risk assessment of a benign breast disease/lesion (BBD) for invasive breast cancer (IBC) is typically done through a longitudinal study. For an infrequently-reported BBD, the shortage of occurrence data alone is a limiting factor to conducting such a study. Here we present an approach based on co-occurrence analysis, to help address this issue. We focus on fibroadenomatoid change (FAC), an under-studied BBD, as our preliminary analysis has suggested its previously unknown significant co-occurrence with IBC.

Methods

A cohort of 1667 female patients enrolled in the Clinical Breast Care Project was identified. A single experienced breast pathologist reviewed all pathology slides for each case and recorded all observed lesions, including FAC. Fibroadenoma (FA) was studied for comparison since FAC had been speculated to be an immature FA. FA and Fibrocystic Changes (FCC) were used for method validation since they have been comprehensively studied. Six common IBC and BBD risk/protective factors were also studied. Co-occurrence analyses were performed using logistic regression models.

Results

Common risk/protective factors were associated with FA, FCC, and IBC in ways consistent with the literature in general, and they were associated with FAC, FA, and FCC in distinct patterns. Age was associated with FAC in a bell-shape curve so that middle-aged women were more likely to have FAC. We report for the first time that FAC is positively associated with IBC with odds ratio (OR) depending on BMI (OR = 6.78, 95%CI = 3.43-13.42 at BMI<25 kg/m²; OR = 2.13, 95%CI = 1.20-3.80 at BMI>25 kg/m²). This association is only significant with HER2-negative IBC subtypes.

Conclusions

We conclude that FAC is a candidate risk factor for HER2-negative IBCs, and it is a distinct disease from FA. Co-occurrence analysis can be used for initial assessment of the risk for IBC from a BBD, which is vital to the study of infrequently-reported BBDs.

Avoiding the major complication of ophthalmic pathology: misdiagnosis. A review of three common diagnostic challenges

Diagnostic errors in ophthalmic pathology are not uncommon. Pathology is a very subjective specialty with several biases dependent on such factors as training, experience, practice patterns, personal anecdotes, and inevitable human error. In addition to these factors, there are many cases where difficulty in diagnosis lies in differentiating between two very closely related, or similar appearing, entities that may have vastly different prognostic consequences. In this paper, we review three challenging areas wherein diagnostic dilemmas may occur. We outline some of the lessons we have learned in arriving at a correct diagnosis, which includes an admission of one's own limitations requiring consultation with other pathology subspecialists, and the use of immunohistochemistry.

Discrepancy rates in liver biopsy reporting

Medical liver biopsy reporting is challenging, and maintaining competency with small case numbers is potentially difficult. This study evaluates the discrepancies identified in cases referred to a specialist centre between the specialist reports and those of the referring general departments. Fifty consecutive recently referred cases were selected, and original and final reports were compared. Discrepancies were classified as per the Royal College of Pathologists guidelines and scored for potential clinical impact. The overall rate of discrepancy was 38% with most of these due to differences in interpretation of morphology. Seventy per cent of these discrepancies were judged to have major clinical impact (26% of all referred cases). This study highlights the need for robust systems of quality control of liver biopsies in a general setting.

Q-Probes studies in anatomic pathology: quality improvement through targeted benchmarking

CONTEXT

The Q-Probes program is a peer-comparison quality assurance service offered by the College of American Pathologists that was created in 1989.

OBJECTIVE

To establish national benchmarks around a specific quality metric at a specific point in time in anatomic pathology (AP).

DESIGN

Q-Probes are based on a voluntary subscription for an individual study. Hospital-based laboratories in the United States, Canada, and 16 other countries have participated. Approximately one-third of all Q-Probes studies address AP metrics. Each Q-Probes study has a primary quality indicator and additional minor indicators.

RESULTS

There have been 52 AP Q-Probes studies addressing process-, outcome-, and structure-related quality assurance issues. These Q-Probes studies often represented the first standardized national benchmark for specific metrics in the disciplines of cytopathology, surgical pathology, and autopsy pathology, and as such have been cited more than 1700 times in peer-reviewed literature. The AP Q-Probes studies that have been repeated over time demonstrate improvement in laboratory performance across an international spectrum.

CONCLUSIONS

The Q-Probes program has produced important national benchmarks in AP, addressing preanalytic, analytic, and postanalytic factors in the disciplines of cytopathology, surgical pathology, and autopsy pathology. Q-Probes study data have been published, cited, and used in the creation of laboratory accreditation standards and other national guidelines.

Whole slide imaging diagnostic concordance with light microscopy for breast needle biopsies

This study investigated the diagnostic accuracy of whole slide imaging (WSI) in breast needle biopsy diagnosis in comparison with standard light microscopy (LM). The study examined the effects of image capture magnification and computer monitor quality on diagnostic concordance of WSI and LM. Four pathologists rendered diagnoses using WSI to examine 85 breast biopsies (92 parts; 786 slides) consisting of benign and malignant cases. Each WSI case was evaluated using images captured at either ×20 or ×40 magnifications and viewed using a Digital Imaging and Communication in Medicine (DICOM) grade, color-calibrated monitor or a standard, desktop liquid-crystal display (LCD) monitor. For each combination, the WSI result was compared with the original, LM diagnosis. The overall concordance rate observed between WSI and LM was 97.1% (95% confidence intervals [CI]: 94.3%-98.5%). After a washout period, all cases were reviewed a second time by each pathologist after using LM, and the second LM diagnosis was compared with the WSI diagnosis rendered by the same pathologist. Intraobserver concordance between WSI and LM was 95.4% (95% CI: 92.2%-97.4%). The second LM diagnoses were also compared with the original LM diagnoses, and the observed interobserver LM concordance rate was 97.3% (95% CI: 93.1%-99.0%). The study data demonstrated that breast needle biopsy diagnoses rendered by WSI were equivalent to diagnoses rendered by LM. No diagnostic differences were detected between the underlying viewing system parameters of monitor quality and image capture resolution. The results of this study demonstrated that WSI can be effectively used in subspecialty diagnostic cases where a minimum amount of tissue is available.

Validation of whole slide imaging for primary diagnosis in surgical pathology

CONTEXT

High-resolution scanning technology provides an opportunity for pathologists to make diagnoses directly from whole slide images (WSIs), but few studies have attempted to validate the diagnoses so obtained.

OBJECTIVE

To compare WSI versus microscope slide diagnoses of previously interpreted cases after a 1-year delayed re-review ("wash-out") period.

DESIGN

An a priori power study estimated that 450 cases might be needed to demonstrate noninferiority, based on a null hypothesis: "The true difference in major discrepancies between WSI and microscope slide review is greater than 4%." Slides of consecutive cases interpreted by 2 pathologists 1 year prior were retrieved from files, and alternate cases were scanned at original magnification of ×20. Each pathologist reviewed his or her cases using either a microscope or imaging application. Independent pathologists identified and classified discrepancies; an independent statistician calculated major and minor discrepancy rates for both WSI and microscope slide review of the previously interpreted cases.

RESULTS

The 607 cases reviewed reflected the subspecialty interests of the 2 pathologists. Study limitations include the lack of cytopathology, hematopathology, or lymphoid cases; the case mix was not enriched with difficult cases; and both pathologists had interpreted several hundred WSI cases before the study to minimize the learning curve. The major and minor discrepancy rates for WSI were 1.65% and 2.31%, whereas rates for microscope slide reviews were 0.99% and 4.93%.

CONCLUSIONS

Based on our assumptions and study design, diagnostic review by WSI was not inferior to microscope slide review (P < .001).

Digital imaging in pathology: whole-slide imaging and beyond

Digital imaging in pathology has undergone an exponential period of growth and expansion catalyzed by changes in imaging hardware and gains in computational processing. Today, digitization of entire glass slides at near the optical resolution limits of light can occur in 60 s. Whole slides can be imaged in fluorescence or by use of multispectral imaging systems. Computational algorithms have been developed for cytometric analysis of cells and proteins in subcellular locations by use of multiplexed antibody staining protocols. Digital imaging is unlocking the potential to integrate primary image features into high-dimensional genomic assays by moving microscopic analysis into the digital age. This review highlights the emerging field of digital pathology and explores the methods and analytic approaches being developed for the application and use of these methods in clinical care and research settings.

Directed peer review in surgical pathology

Second pathologist peer review is used in many surgical laboratory quality-assurance programs to detect error. Directed peer review is 1 method of second review and involves the selection of specific case types, such as cases from a particular site of anatomic origin. The benefits of using the directed peer review method are unique and directed peer review detects both errors in diagnostic accuracy and precision and this detection may be used to improve practice. We utilize the Lean quality improvement A3 method of problem solving to investigate these issues. The A3 method defines surgical pathology diagnostic error and describes the current state in surgical pathology, performs root cause analysis, hypothesizes an ideal state, and provides opportunities for improvement in error reduction. Published data indicate that directed peer review practices may be used to prevent active cognitive errors that lead to patient harm. Pathologists also may use directed peer review data to target latent factors that contribute to error and improve diagnostic precision.

Concordance between whole-slide imaging and light microscopy for routine surgical pathology

The use of high-resolution digital images of histopathology slides as a routine diagnostic tool for surgical pathology was investigated. The study purpose was to determine the diagnostic concordance between pathologic interpretations using whole-slide imaging and standard light microscopy. Two hundred fifty-one consecutive surgical pathology cases (312 parts, 1085 slides) from a single pathology service were included in the study after cases had been signed out and reports generated. A broad array of diagnostic challenges and tissue sources were represented, including 52 neoplastic cases. All cases were digitized at ×20 and presented to 2 pathologists for diagnosis using whole-slide imaging as the sole diagnostic tool. Diagnoses rendered by the whole-slide imaging pathologists were compared with the original light microscopy diagnoses. Overall concordance between whole-slide imaging and light microscopy as determined by a third pathologist and jury panel was 96.5% (95% confidence interval, 94.8%-98.3%). Concordance between whole-slide imaging pathologists was 97.7% (95% confidence interval, 94.7%-99.2%). Five cases were discordant between the whole-slide imaging diagnosis and the original light microscopy diagnosis, of which 2 were clinically significant. Discordance resulted from interpretive criteria or diagnostic error. The whole-slide imaging modality did not contribute to diagnostic differences. Problems encountered by the whole-slide imaging pathologists primarily involved the inability to clearly visualize nuclear detail or microscopic organisms. Technical difficulties associated with image scanning required at least 1 slide be rescanned in 13% of the cases. Technical and operational issues associated with whole-slide imaging scanning devices used in this study were found to be the most significant obstacle to the use of whole-slide imaging in general surgical pathology.

Telecytology: Clinical applications, current challenges, and future benefits

Telecytology is the interpretation of cytology material at a distance using digital images. For more than a decade, pioneering efforts to introduce telecytology into clinical practice have been reported. A Medline search for "telecytology" and "cytology" reveals a voluminous literature, though much of what has been published to date is based on technologies that are rapidly becoming obsolete. The technological limitations of previous techniques, including the transmission of static digital images and dynamic streaming images, have limited telecytology to minor niches. The primary problem with these technologies is that the remote viewer can only see a small fraction of the material on the original slides, introducing the possibility of diagnostic error based not only on image quality but also on image selection. Remote robotic microscopy offers one possible solution to this problem, but to date has found limited acceptance, principally attributable to slow operating times. Whole slide imaging seems to be a much more promising solution, though cytology-specific literature regarding its use is still scant. The advent of whole slide imaging opens up new possibilities for telecytology by enabling high-quality images of entire cytology specimens to be available to anyone, anywhere via the Internet. Although challenges remain, especially with regard to capturing the full microscopy experience including multiple planes of focus and sharp high-powered images, rapidly advancing technology promises to overcome these limitations. Increasing application of whole slide imaging technology in surgical pathology will undoubtedly also increase its application to cytology due to the increasing affordability and practicality of the equipment as it serves a larger number of useful roles within a pathology department. The current and expanding applications of telecytology for clinical practice, education, quality assurance, and testing will be reviewed.

Intra-operative frozen section analysis for suspected early-stage ovarian cancer: 11 years of Gateshead Cancer Centre experience

OBJECTIVE

In centres in which intra-operative frozen section (FS) analysis is not performed, 'apparent' early-stage ovarian cancer diagnosed after surgery on paraffin section may require further restaging laparotomy or adjuvant chemotherapy. Previous studies on FS analysis have reported high sensitivity, specificity and overall accuracy. The objective of this article is to present the largest published dataset on the accuracy of FS analysis over an 11-year period from a single institution.

DESIGN

Diagnostic test accuracy.

SETTING

Northern Gynaecological Oncology Centre and Department of Cellular Pathology, Gateshead, UK.

POPULATION

1439 intra-operative FS analyses performed between January 2000 and December 2010 for suspected ovarian cancer.

METHODS

Prospectively collected data on FS analysis were compared with gold standard paraffin section.

MAIN OUTCOME MEASURES

Sensitivity, specificity, likelihood ratios and post-test probability.

RESULTS

The overall sensitivity and specificity of FS analysis were 91.2% and 98.6%, respectively. Positive and negative likelihood ratios were 64.7% and 0.09%, respectively. The pre-test probability of an ovarian tumour being borderline or malignant was 45.8%. When FS analysis was reported to be positive, the post-test probability increased to 98% (confidence interval, 97-99%). Conversely, when FS analysis was reported to be negative, the post-test probability decreased to 7% (confidence interval, 6-9%). The majority of false test results were either borderline tumours or of mucinous differentiation.

CONCLUSIONS

Intra-operative FS analysis has excellent diagnostic test accuracy and assists gynaecological oncologists to perform the appropriate surgery in 95% of cases, thereby preventing the morbidity of surgical staging in benign cases and the morbidity of restaging procedures or chemotherapy in early-stage malignant tumours.

Study of amended reports to evaluate and improve surgical pathology processes

BACKGROUND

: Amended surgical pathology reports record defects in the process of transforming tissue specimens into diagnostic information.

OBJECTIVE

: Systematic study of amended reports tests 2 hypotheses: (a) that tracking amendment frequencies and the distribution of amendment types reveals relevant aspects of quality in surgical pathology's daily transformation of specimens into diagnoses and (b) that such tracking measures the effect, or lack of effect, of efforts to improve surgical pathology processes.

MATERIALS AND METHODS

: We applied a binary definition of altered reports as either amendments or addenda and a taxonomy of defects that caused amendments as misidentifications, specimen defects, misinterpretations, and report defects. During the introduction of a LEAN process improvement approach-the Henry Ford Productions System-we followed trends in amendment rates and defect fractions to (a) evaluate specific interventions, (b) sort case-by-case root causes of misidentifications, specimen defects, and misinterpretations, and (c) audit the ongoing accuracy of the classification of changed reports. LEAN is the management and production system of the Toyota Motor Corporation that promotes continuous improvement; it considers wasted resources expended for purposes other than creating value for end customers and targets such expenditures for elimination.

RESULTS

: Introduction of real-time editing of amendments saw annual amendment rates increase from 4.8/1000 to 10.1/1000 and then decrease in an incremental manner to 5.6/1000 as Henry Ford Productions System-specific interventions were introduced. Before introduction of HFPS interventions, about a fifth of the amendments were due to misidentifications, a 10th were due to specimen defects, a quarter due to misinterpretation, and almost half were due to report defects. During the period of the initial application of HFPS, the fraction of amendments due to misidentifications decreased as those due to report defects increased, in a statistically linked manner. As HFPS interventions took hold, misidentifications fell from 16% to 9%, specimen defect rates remained variable, ranging between 2% and 11%, and misinterpretations fell from 18% to 3%. Reciprocally, report defects rose from 64% to 83% of all amendment-causing defects. A case-by-case study of misidentifications, specimen defects, and misinterpretations found that (a) intervention at the specimen collection level had disappointingly little effect on patient misidentifications; (b) standardization of specimen accession and gross examination reduced only specimen defects surrounding ancillary testing; but (c) a double review of breast and prostate cases was associated with drastically reduced misinterpretation defects. Finally, audit of both amendments and addenda demonstrated that 10% of the so-called addenda actually qualified as amendments.

DISCUSSION

: Monitored by the consistent taxonomy, rates of amended reports first rose, then fell. Examining specific defect categories provided information for evaluating specific LEAN interventions. Tracking the downward trend of amendment rates seemed to document the overall success of surgical pathology quality improvement efforts. Process improvements modestly decreased fractions of misidentifications and markedly decreased misinterpretation fractions. Classification integrity requires real time, independent editing of both amendments (changed reports) and addenda (addition to reports).

Digital imaging in cytopathology

Rapid advances are occurring in the field of cytopathology, particularly in the field of digital imaging. Today, digital images are used in a variety of settings including education (E-education), as a substitute to multiheaded sessions, multisite conferences, publications, cytopathology web pages, cytology proficiency testing, telecytology, consultation through telecytology, and automated screening of Pap test slides. The accessibility provided by digital imaging in cytopathology can improve the quality and efficiency of cytopathology services, primarily by getting the expert cytopathologist to remotely look at the slide. This improved accessibility saves time and alleviates the need to ship slides, wait for glass slides, or transport pathologists. Whole slide imaging (WSI) is a digital imaging modality that uses computerized technology to scan and convert pathology and cytology glass slides into digital images (digital slides) that can be viewed remotely on a workstation using viewing software. In spite of the many advances, challenges remain such as the expensive initial set-up costs, workflow interruption, length of time to scan whole slides, large storage size for WSI, bandwidth restrictions, undefined legal implications, professional reluctance, and lack of standardization in the imaging process.

Clinical examination and validation of primary diagnosis in anatomic pathology using whole slide digital images

CONTEXT

Novel anatomic pathology technologies allow pathologists to digitally view and diagnose cases. Although digital pathology advocates champion its strengths and move to integrate it into practice and workflow, the capabilities and limitations of digital slides have not been fully investigated.

OBJECTIVES

To estimate intrapathologist diagnostic discrepancy between glass and digital slides and to determine pathologists' diagnostic certainty when diagnosing with the 2 formats.

DESIGN

Intrapathologist diagnostic consistency between glass and digital slides was measured. Three pathologists diagnosed 101 cases digitally and with corresponding glass slides. Discrepancies between formats were evaluated, and diagnostic precision and certainty were compared.

RESULTS

A total of 606 diagnoses were evaluated in pairs (202 per pathologist). Seven cases did not transfer to the database and were eliminated from further study. We report no discrepancies between media in 75%, 87%, and 83% of the cases diagnosed by the 3 pathologists, respectively; significant discrepancies were identified in 3%, 3%, and 7% of cases by each pathologist. In total, we identified significant clinical and therapeutic discrepancies in 13 of 296 cases (4.4%). The certainty values provided by each pathologist were similar between formats.

CONCLUSIONS

This study did not detect significant differences between diagnoses based on digital and glass slides. We believe that this study further supports the integration of digital slides into pathology workflow, particularly considering the low rate of discrepancy documented here.

Diagnostic Concordance of Histologic Lung Cancer Type Between Bronchial Biopsy and Cytology Specimens Taken During the Same Bronchoscopic Procedure

Context.—The diagnosis of lung cancer is often confirmed by cytology and biopsy specimens obtained during a bronchoscopic procedure. At our institution, these specimens are read by different pathologists, and the rate of concordance was not known.

Objectives.—To evaluate the concordance rate in the diagnosis of lung cancer types between cytology and biopsy specimens and to correlate discordance with patient outcome.

Design.—Specimens obtained during the same procedure, between January 1, 2000, and December 31, 2005, were identified. Cases with cytology and biopsy specimens positive for cancer were evaluated for concordance of histologic type, small cell versus non–small cell lung carcinoma. Cases with different types were considered discordant, and slides were reviewed.

Results.—Of 231 cases, 225 (97.4%) had concordant diagnoses. Discordance was the result of misinterpretation of undifferentiated carcinoma, overinterpretation of squamous dysplasia, interpretation of suboptimal specimens with necrosis and crush artifact, and sampling error.

Conclusions.—Even though the cytology and biopsy specimens were reviewed by different pathologists, the concordance rate for histologic type at our institution was high, emphasizing that this is a safe practice. The few discordant cases did not affect the patient's outcome.

Detection and classification of diagnostic discrepancies (errors) in surgical pathology

Detecting and classifying error in a surgical pathology (SP) practice is an important part of a comprehensive quality assurance program. There are a number of mechanisms to detect error, including secondary review, examination of amended reports, correlation studies (cytology-histology and frozen-final diagnosis correlation). These different detection methods are reviewed in this paper. Additionally, the most common methods for error classification are also reviewed, along with the benefits and limitations of each. Although there is presently no gold standard for detecting or classifying errors in SP, based on this review of the literature, it is clearly good practice to consistently apply a standard method. Most importantly, these data should be incorporated into quality assurance and quality improvement activities, such that departments strive to reduce errors, and to help improve overall quality in SP.

Periodic review of pathology training program teaching files: a quality improvement study

Pathology training programs typically retain teaching files of classic and unusual diagnostic cases. Since diagnostic criteria and terminology are mutable, we reviewed a surgical pathology teaching archive to determine if the materials continued to be acceptable for educational purposes. Each case (from 2001-2003) consisted of 1 to 3 slides and a 3 x 5 card with clinical information and the diagnosis. Cases were reviewed at a daily faculty consensus conference and categorized as follows: no diagnostic change; diagnosis added; or changed diagnosis. Slides were entirely missing from 79 (35.0%) of the 226 cases reviewed. Of the remaining 147 cases, 28 (19.0%) required additional clinical information and/or slides. The final disposition of the 147 cases was as follows: diagnosis unchanged, 126 (85.7%); diagnosis added, 15 (10.2%); and diagnosis changed, 6 (4.1%). Teaching files should be subject to prospective and retrospective controls to preserve the quality of the educational experience.