Departmental audit in surgical anatomical pathology

Validation of digital pathology imaging for primary histopathological diagnosis

AIMS

Digital pathology (DP) offers advantages over glass slide microscopy (GS), but data demonstrating a statistically valid equivalent (i.e. non-inferior) performance of DP against GS are required to permit its use in diagnosis. The aim of this study is to provide evidence of non-inferiority.

METHODS AND RESULTS

Seventeen pathologists re-reported 3017 cases by DP. Of these, 1009 were re-reported by the same pathologist, and 2008 by a different pathologist. Re-examination of 10 138 scanned slides (2.22 terabytes) produced 72 variances between GS and DP reports, including 21 clinically significant variances. Ground truth lay with GS in 12 cases and with DP in nine cases. These results are within the 95% confidence interval for existing intraobserver and interobserver variability, proving that DP is non-inferior to GS. In three cases, the digital platform was deemed to be responsible for the variance, including a gastric biopsy, where Helicobacter pylori only became visible on slides scanned at the ×60 setting, and a bronchial biopsy and penile biopsy, where dysplasia was reported on DP but was not present on GS.

CONCLUSIONS

This is one of the largest studies proving that DP is equivalent to GS for the diagnosis of histopathology specimens. Error rates are similar in both platforms, although some problems e.g. detection of bacteria, are predictable.

Factors that impact turnaround time of surgical pathology specimens in an academic institution

Turnaround time of laboratory results is important for customer satisfaction. The College of American Pathologists' checklist requires an analytic turnaround time of 2 days or less for most routine cases and lets every hospital define what a routine specimen is. The objective of this study was to analyze which factors impact turnaround time of nonbiopsy surgical pathology specimens. We calculated the turnaround time from receipt to verification of results (adjusted for weekends and holidays) for all nonbiopsy surgical specimens during a 2-week period. Factors studied included tissue type, number of slides per case, decalcification, immunohistochemistry, consultations with other pathologists, and diagnosis. Univariate and multivariate analyses were performed. A total of 713 specimens were analyzed, 551 (77%) were verified within 2 days and 162 (23%) in 3 days or more. Lung, gastrointestinal, breast, and genitourinary specimens showed the highest percentage of cases being signed out in over 3 days. Diagnosis of malignancy (including staging of the neoplasia), consultation with other pathologists, having had a frozen section, and use of immunohistochemical stains were significantly associated with increased turnaround time in univariate analysis. Decalcification was not associated with increased turnaround time. In multivariate analysis, consultation with other pathologists, use of immunohistochemistry, diagnosis of malignancy, and the number of slides studied continued to be significantly associated with prolonged turnaround time. Our findings suggest that diagnosis of malignancy is central to significantly prolonging the turnaround time for surgical pathology specimens, thus institutions that serve cancer centers will have longer turnaround time than those that do not.

[Internal quality control of histological diagnosis in pathology. A nine-year experience]

Internal quality control (IQC) is a necessary component of total quality management. We report our experience with an internal audit scheme focusing on the histological diagnosis. We outline other strategies of IQC and analyze the causes of errors and ways to prevent them. Some practical guidelines to initiate this type of procedure are presented. Our audit was designed to check the accuracy of diagnosis, the clarity and completeness of the report, the quality of the documents leading to the diagnosis, and the turn-around time. It consisted of a retrospective analysis of 4185 randomly selected cases (representing 2% of all cases), over nine years. The control took place once a week and was done by two pathologists working as a team. The mean time spent by each pathologist was 45 minutes per week. Errors were scored using a 3-level grading scheme depending on their potential harm or impact on patient care. The overall rate of errors was 1.1%, and 0.1% of errors were potentially harmful to the patients. A single case (0.02%), in which a cancer was missed, had a real impact on patient care. Retrospective analysis of randomly selected cases mirrors the overall activity of a surgical pathology department. Nevertheless, each lab has to develop its own strategy of IQC, based on its size, its functioning, and its objectives. Although it may be difficult to initiate quality assurance when medical time is already limited, it is a helpful procedure in a more and more demanding medical and societal context and a pragmatic step towards "culture of quality".

Patient safety in anatomic pathology: measuring discrepancy frequencies and causes

CONTEXT

Anatomic pathology discrepancy frequencies have not been rigorously studied.

OBJECTIVE

To determine the frequency of anatomic pathology discrepancies and the causes of these discrepancies.

DESIGN

Participants in the College of American Pathologists Q-Probes program self-reported the number of anatomic pathology discrepancies in their laboratories by prospectively performing secondary review (post-sign-out) of 100 surgical pathology or cytology specimens. Reasons for the secondary review included conferences, external review, internal quality assurance policy, and physician request.

PARTICIPANTS

Seventy-four laboratories self-reported data.

MAIN OUTCOME MEASURES

Frequency of anatomic pathology discrepancy; type of discrepancy (ie, change in margin status, change in diagnosis, change in patient information, or typographic error); effect of discrepancy on patient outcome (ie, no harm, near miss, or harm); and clarity of report.

RESULTS

The mean and median laboratory discrepancy frequencies were 6.7% and 5.1%, respectively. Forty-eight percent of all discrepancies were due to a change within the same category of interpretation (eg, 1 tumor type was changed to another tumor type). Twenty-one percent of all discrepancies were due to a change across categories of interpretation (eg, a benign diagnosis was changed to a malignant diagnosis). Although the majority of discrepancies had no effect on patient care, 5.3% had a moderate or marked effect on patient care.Conclusions.-This study establishes a mean multi-institutional discrepancy frequency (related to secondary review) of 6.7%.

Anatomic Pathology Databases and Patient Safety

Context.—The utility of anatomic pathology discrepancies has not been rigorously studied.

Objective.—To outline how databases may be used to study anatomic pathology patient safety.

Design.—The Agency for Healthcare Research and Quality funded the creation of a national anatomic pathology errors database to establish benchmarks for error frequency. The database is used to track more frequent errors and errors that result in more serious harm, in order to design quality improvement interventions intended to reduce these types of errors. In the first year of funding, 4 institutions (University of Pittsburgh, Henry Ford Hospital, University of Iowa, and Western Pennsylvania Hospital) reported cytologic-histologic correlation error data after standardizing correlation methods. Root cause analysis was performed to determine sources of error, and error reduction plans were implemented.

Participants.—Four institutions self-reported anatomic pathology error data.

Main Outcome Measures.—Frequency of cytologic-histologic correlation error, case type, cause of error (sampling or interpretation), and effect of error on patient outcome (ie, no harm, near miss, and harm).

Results.—The institutional gynecologic cytologic-histologic correlation error frequency ranged from 0.17% to 0.63%, using the denominator of all Papanicolaou tests. Based on the nongynecologic cytologic-histologic correlation data, the specimen sites with the highest discrepancy frequency (by project site) were lung (ranging from 16.5% to 62.3% of all errors) and urinary bladder (ranging from 4.4% to 25.0%). Most errors detected by the gynecologic cytologic-histologic correlation process were no-harm events (ranging from 10.7% to 43.2% by project site). Root cause analysis identified sources of error on both the clinical and pathology sides of the process, and error intervention programs are currently being implemented to improve patient safety.

Conclusions.—A multi-institutional anatomic pathology error database may be used to benchmark practices and target specific high-frequency errors or errors with high clinical impact. These error reduction programs have national import.

Pathological quality assurance in gastro-intestinal cancer

Quality assurance has become an integrated and important part of surgical pathology. Not only laboratory quality systems and quality control of pathology reporting have been introduced, also interdisciplinary quality systems are being developed. This review focuses on the different aspects of quality assurance that can nowadays be used in the daily practice of pathology management of gastrointestinal cancers, especially, gastric- and colorectal cancer. Own data are, especially, derived from the recently conducted clinical trial on pre-operative radiotherapy for rectal cancer and emphasize the importance of multidisciplinary approaches.

Pathology and patient safety: the critical role of pathology informatics in error reduction and quality initiatives

Understanding the role of pathology informatics in patient safety entails an introduction to terminology and projects that have represented efforts to date in this area. The authors provide a short alphabetized introduction to several "buzzwords" and terms related to tools and processes that are used by health care research experts and workers involved in patient safety initiatives. The authors also include short descriptions of key health care research and patient safety projects that are relevant to pathology. They aim to highlight the areas where pathology informatics in all of its flavors (production systems provided by vendors as well as research and development efforts) can play a role in promoting patient safety.

Improving patient safety by examining pathology errors

A considerable void exists in the information available regarding anatomic pathology diagnostic errors and their impact on clinical outcomes. To fill this void and improve patient safety, four institutional pathology departments (University of Pittsburgh, Western Pennsylvania Hospital, University of Iowa Hospitals and Clinics, and Henry Ford Hospital System) have proposed the development of a voluntary, Web-based, multi-institutional database for the collection and analysis of diagnostic errors. These institutions intend to use these data proactively to implement internal changes in pathology practice and to measure the effect of such changes on errors and clinical outcomes. They believe that the successful implementation of this project will result in the study of other types of diagnostic pathology error and the expansion to national participation. The project will involve the collection of multi-institutional anatomic pathology diagnostic errors in a large database that will facilitate a more detailed analysis of these errors, including their effect on patient outcomes. Participating institutions will perform root cause analysis for diagnostic errors and plan and execute appropriate process changes aimed at error reduction. The success of these interventions will be tracked through analysis of postintervention error data collected in the database. Based on their preliminary studies, these institutions proposed the following specific aims: Specific aim #1: To use a Web-based database to collect diagnostic errors detected by cytologic histologic correlation and by second-pathologist review of conference cases. Specific aim #2: To analyze the collected error data quantitatively and generate quality performance reports that are useful for institutional quality improvement programs. Specific aim #3: To plan and implement interventions to reduce errors and improve clinical outcomes, based on information derived from root cause analysis of diagnostic errors. Specific aim #4: To assess the success of implemented interventions by quantitative measure of postinterventional errors and clinical outcomes and by qualitative assessment by project participants. Funding for this project was approved by the Agency for Health Care Research and Quality in September 2002, and data collection and analysis are ongoing. Over 5000 errors have been collected in the database, and the clinical outcomes of these errors have been tracked. At a national meeting in November 2003, root cause analysis was performed to determine causes of errors. The findings of these root cause analyses have been presented at national pathology meetings and are currently being published.

Pathologists' assistants practice: a measurement of performance

Despite their widespread utilization, little is known about the quality of pathologists' assistants' services. Pathologists' assistants' performance was compared with pathology residents' performance using the metrics of lymph node retrieval and tissue resubmission rates. Lymph node retrieval was calculated by retrospective review of surgical pathology reports from a sample of axillary dissection, mastectomy, and colorectal specimens. Tissue resubmission rates were calculated by retrospective review of a sample of general surgical pathology reports. Pathologists' assistants retrieved a significantly greater total number of lymph nodes compared with pathology residents; however, there was no difference in the total number of positive lymph nodes retrieved. Cases for which pathologists' assistants performed the gross examination had a significantly decreased resubmission rate compared with those performed by residents. In this setting, the gross examination performance of pathologists' assistants was equivalent to or superior to that of pathology residents. These results provide the first information available relating to pathologists' assistants' performance in surgical pathology.

Pathology data in the central databases of multicenter randomized trials need to be based on pathology reports and controlled by trained quality managers

PURPOSE

Randomized multicenter trials form the basis of health care development. Regarding cancer research, pathology data are crucial. To maintain the quality of these trials, the auditing of subsequent processes is necessary. The aim of the present study was to examine the completeness and accuracy of data obtained from a special-purpose standardized pathology form compared with the data available through traditional hospital pathology reports.

PATIENTS AND METHODS

A retrospective comparison of pathology data case record forms with hospital pathology reports was performed using the data from 300 patients with primary rectal cancer. All of these patients had been included in a large multicenter trial in the Netherlands. Three independent audits were carried out. Special attention was given to the accuracy of parameters, which are important for prognosis and treatment decisions. Furthermore, various factors that possibly influence the occurrence of errors were investigated.

RESULTS

Quality control of the pathology data revealed a high accuracy of 86.5% of all data items. However, only one third of the forms were complete and correct. Missing values were most prominent in the number of lymph nodes examined, whereas most errors were made in relation to the circumferential margin. Trained review pathologists made fewer major errors. Discrepancies were detected in all control rounds.

CONCLUSION

Successive rounds of quality control are required for accuracy and completeness of pathology data in multicenter trials. In addition to the special-purpose pathology forms, original pathology reports have to be collected, and the data should also be controlled by a trained pathology quality manager.

Errors in histopathology reporting: detection and avoidance

The histopathological diagnosis is the bedrock of modern oncology, and plays a major role in the treatment of many other types of disease. Errors in these reports can critically affect patient care and may become the subject of media concern. This article considers how audit in histopathology can provide information about errors and inconsistencies in the diagnosis of surgical specimens. The use of audit to generate information about the background level of errors in pathology reports is reviewed, along with findings about the nature of these errors and the types of specimens more commonly affected. Generic audit strategies that can be used to minimize the risk of errors in reports are discussed, together with the use of audit to evaluate diagnostic criteria and pathological scoring or grading systems. The role of audit in determining the informational content of reports is included, and there is consideration of the relationship between sample size and error rates. The limited extent to which audit can be used to assess the performance of individual pathologists is also covered.