Retrospective blinded review of interpretational diagnostic discrepancies in surgical pathology: 18 years of experience at a tertiary care facility.

We evaluated our quality assurance (QA) methods and QA consensus conference model for assessing the rate of interpretational diagnostic errors and trend of errors. Using monthly QA reports from review of frozen section- permanent section correlation and amended reports, all cases with interpretational diagnostic errors were identified. Retrospective blinded review of study cases were independently performed by all staff pathologist and subsequently discussed in QA conference sessions. 277 (.07%) interpretational errors were identified from 1993-2010. Errors with patient consequences comprised 15% of all errors, 4% of which were major errors. More than half (57%) of the errors were identified on review of frozen section- permanent section correlation and accounted for 64 % of all errors with patient consequence and 45% of major errors. Comparison of errors between two equally divided time periods (1993-2001 and 2002-2010) showed significant error reduction (p< 0.05). 64% of all errors, 61% of errors with patient consequence and 73% of major errors were a consequence of incorrect interpretation of the biologic behavior of the neoplasm. To conclude, we propose this quality assurance model as an effective tool for assessing interpretational errors, particularly those with significant patient consequences, enhancing participation of pathologists and reducing errors.