Errors in Thyroid Gland Fine-Needle Aspiration

Abstract

Scant published data exist on redesigning pathology practice based on error data. In this first step of an Agency for Healthcare Research and Quality patient safety project, we measured the performance metrics of thyroid gland fine-needle aspiration, performed root cause analysis to determine the causes of error, and proposed error-reduction initiatives to address specific errors. Eleven cytologists signed out 1,543 thyroid gland aspirates in 2 years, and surgical pathology follow-up was obtained in 364 patients. Of the 364 patients, 91 (25.0%) had a false-negative diagnosis and 36 (9.9%) a false-positive diagnosis. Root cause analysis showed that major sources of error were pre-analytic (poor specimen quality) and analytic (interpretation of unsatisfactory specimens as nonneoplastic and lack of diagnostic category standardization). We currently are evaluating the effectiveness of error reduction initiatives that target pre-analytic and analytic portions of the diagnostic pathway.

Diagnostic accuracy of fine-needle aspiration versus core-needle biopsy for the diagnosis of thyroid malignancy in a clinical cohort

“…A study of errors in thyroid gland FNA [28] demonstrated that the root cause of most errors in the FNA diagnosis was poor specimen quality and most were not caused by cytologist misinterpretation of good samples. Therefore, the quality of FNA samples may affect the diagnostic accuracy as well as the diagnostic adequacy of FNA.…”

Prognostic factors and follow-up of patients with differentiated thyroid carcinoma with false negative or nondiagnostic FNAC before surgery. Comparison with a control group

“…The false negative results of FNAC constitute a serious limitation of this technique since malignant lesions would go untreated. The prevalence of false negative results of FNAC in some series may be as high as 20-31% [25][26][27], depending on the quality of smears and the experience of the cytologist in interpreting the findings [26][27][28][29]. But another determining factor in the rate of false negative results of FNAC is the number of patients with benign FNAC who undergo surgery [30].…”

Epidemiologie, Pathophysiologie, leitliniengerechte Diagnostik und Therapie des Schilddrüsenknotens

“…Eindeutige klinische und sonographische Malignitätskriterien sollten auch bei benignem FNB-Befund die Indikation zur histologischen Abklärung und damit der Operation sein [30]. Insbesondere eine geringe Qualität des Punktats durch mangelnde Erfahrung des Punkteurs oder fehlende Erfahrung des Zytopathologen sowie eine fehlende Standardisierung diagnostischer Kategorien sind jedoch häufige Ursachen für falsch negative oder falsch positive FNB-Befunde [31,32]. Die beste qualitätsstei-gernde Maßnahme ist der konsequente Abgleich der FNB-Ergebnisse mit den postoperativen histologischen Befunden.…”