Process improvement in thyroid fine needle aspiration: Standardizing number of smears for enhanced adequacy and diagnosis.

Abstract

Fine-needle aspiration (FNA) is a safe, cost-effective diagnostic procedure used in the evaluation of thyroid nodules. The number of thyroid FNAs has dramatically increased over the past few years. In the absence of standardized procedures regarding the number of needle passes needed for diagnosis and the lack of clarity on the use of conventional smears (CS) versus liquid-based preparations (LBP), the demand of thyroid FNAs has led to increased workload on cytology laboratories, which can negatively affect patient safety. We implemented a standardized two needle passes for CS and collection of all needle rinses and additional pass material in CytoRich Red for ThinPrep LBP and compared the non-diagnostic and diagnostic rates before and after this intervention. There were 290 pre-intervention cases and 348 post-intervention cases; of which, there were 17 (5.9%) non-diagnostic cases of the pre-intervention group and 27 (7.8) non-diagnostic cases of the post-intervention group. There was no statistically significant difference in non-diagnostic and diagnostic rates before and after the change (p = 0.347 by two-tailed Z test).