Patterns of Major Frozen Section Interpretation Error: An In-Depth Analysis From a Complex Academic Surgical Pathology Practice

• Published in: American journal of clinical pathology Vol. 160; no. 3; pp. 247 - 254
• Main Authors: Dehan, Lauren M, Lewis, James S, Mehrad, Mitra, Ely, Kim A
• Format: Journal Article
• Language: English
• Published: US Oxford University Press 01-09-2023
• Subjects: Analysis; Cancer; Carcinoma; Discordance; Dysplasia; Pathology; Quality assurance; Quality control; Surgeons; Thorax; Accuracy; Major; Discrepancy; Misinterpretation; Discordance; Error; Intraoperative consultation; Frozen section
• ISSN: 0002-9173; 1943-7722
• DOI: 10.1093/ajcp/aqad040

Abstract
Objectives
To establish baseline error rates due to misinterpretation and to identify scenarios in which major errors were most common and potentially preventable.
Methods
Our database was queried over a 3-year period for major discrepancies due to misinterpretation. These were stratified by histomorphologic setting, service, availability/type of prior material, and years of experience and subspecialization of the interpreting pathologist.
Results
The overall discordance rate between frozen section (FS) and final diagnoses was 2.9% (199/6,910). Seventy-two errors were due to interpretation, of which 34 (47.2%) were major. Major error rates were highest on the gastrointestinal and thoracic services. Of major discrepancies, 82.4% were rendered in subdisciplines outside those of the FS pathologist. Pathologists with fewer than 10 years’ experience made more errors than those with more experience (55.9% vs 23.5%, P = .006). Major error rates were greater for cases without previous material compared to those with a prior glass slide (47.1% vs 17.6%, P = .009). Common histomorphologic scenarios in which disagreements were made involved discriminating mesothelial cells from carcinoma (20.6%) and accurately recognizing squamous carcinoma/severe dysplasia (17.6%).
Conclusions
To improve performance and decrease future misdiagnoses, monitoring discordances should be a continuous component of surgical pathology quality assurance programs.