Endocrine Abstracts

University Hospital Limerick (UHL) is a large model 4 hospital in Ireland’s Midwest serving a population of ~413,000 people. The radiology department performs an average of 220 thyroid fine needle aspiration biopsies (FNABs) per year. The aim of this study was to determine how many non-diagnostic or unsatisfactory results are returned, necessitating repeat FNAB. Data was collected on the previous 502 thyroid FNAB results using the hospital laboratory information system. Of the 502 thyroid FNAB results, 7 were excluded as inappropriately coded results and 495 results were included and classified according to their Royal College of Pathologists Thy Staging System category. Of these, Thy1/Thy1c n = 124 (25%), Thy2/Thy2c n = 240 (48%), Thy 3a n = 98 (20%), Thy3f n = 17 (2%), Thy4 n = 10 (2%) and Thy5 n = 6 (1%). One quarter of thyroid FNABs acquired are non-diagnostic or unsatisfactory, necessitating repeat procedures. Thy1c (n = 25, 5%) results are not thought to be operator dependent. Excluding these, there remains one fifth of thyroid FNABs reported as non-diagnostic or unsatisfactory. This figure is higher than the figure recommended by the Royal College of Pathologists. The frequency of non-diagnostic results may be affected by the lesion characteristics, accuracy of localisation, number of aspirations, needle gauge and aspiration technique. Nonetheless it is important to minimise non-diagnostic results which carry with them financial and time burden along with impacts on patient satisfaction and potential delay in diagnosis. Our institution does not have a cytopathology service with thyroid FNABs processed and reported externally. The provision of rapid onsite evaluation of acquired specimen adequacy by a skilled cytopathologist is an evidence based approach to reduce non-diagnostic results and could be considered in our institution. Further analysis of the imaging characteristics from the biopsied nodules at UHL is also needed to determine if certain characteristics are associated with a non-diagnostic biopsy.