Reducing non diagnostic thyroid cytology using on-site adequacy assessment performed by junior medical staff

Abstract

Objective:To assess efficacy of bedside cytology assessment of thyroid fine needle aspirate samples performed by junior medical staff compared to cytologists. Methods: Retrospective analysis was performed of 1490 thyroid fine needle aspirates. Samples were divided into three groups: cellular adequacy assessment performed by cytologists, interns, and no onsite adequacy assessment (blind). A 45-minute training session was provided to medical interns with the aim of identifying whether adequate cellular material was demonstrated, as defined by the Bethesda criteria. The primary outcome was the rate of nondiagnostic samples, and the secondary outcome was the number of fine needle aspirate passes required to reach sample adequacy. Results: The incidence of non-diagnostic samples for the cytologist, blind, and intern groups were 6.90%, 17.1% and 14.0% respectively (p<0.001). There was no statistically significant difference in non-diagnostic rate between the blind and intern groups. Significantly more aspirates required more than two passes in the cytologist group (74.8%) and blind (94.7%) compared to the intern group (58.7%, p<0.001). Conclusions: On-site adequacy assessment performed by cytopathologists is the gold standard for minimising non-diagnostic thyroid FNAs, however, medical staff with minimal anatomical pathology experience can be trained to perform on-site adequacy assessment and improve outcomes with the implementation of a simple targeted training program.