Thyroid Fine Needle Aspiration: Successful Prospective Implementation of Strategies to Eliminate Unnecessary Biopsy in the Veteran Population

Abstract

Thyroid nodules are prevalent in over half the general population. Several multidisciplinary societies have management recommendations. However, the majority of data to support these guidelines are derived from studies of predominantly younger and female populations. This study's aim was to evaluate characteristics of thyroid nodules in a largely older and male Veteran population and apply these findings prospectively to reduce unnecessary thyroid fine needle aspiration (FNA). Over a 4-year period, all ultrasound-guided FNA of thyroid nodules performed in our department were reviewed. Sonographic features, patterns, and histopathology were evaluated. A prospective strategy of avoiding FNA in all lesions matching imaging patterns of benignity was implemented and positive predictive value (PPV) of malignancy was calculated and compared to the retrospective data. Retrospectively, FNA was performed on 351 successive thyroid nodules, 9 of which were malignant. Statistically significant malignant features include presence of microcalcifications, irregular or amorphous morphology, taller-than-wide shape, spiculated margins, vascularity, and lymphadenopathy. PPV of thyroid FNA was 2.6% in this period. Four sonographic patterns were 100% specific for benignity, including: "spongiform," "cyst with a colloid clot," "giraffe," and "white knight" patterns. Over 23 months, prospective avoidance of FNA of lesions characterized as a benign pattern (159 nodules) was implemented and PPV was calculated as 7.2% resulting in a cost savings of $477,000. Four sonographic patterns were 100% specific for benignity in the older and predominantly male Veteran population. Strict prospective application of avoiding biopsy in these benign patterns resulted in a decrease of unnecessary biopsies, decrease in patient morbidity, and improved allocation of health care resources.