Survey of cytopathologists and cytotechnologists for the clinical impact of the use of atypia or follicular lesion of undetermined significance.

backgroundThe cytologic diagnosis of atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) is controversial because of variation in how it is applied in practice, as well as uncertainty about patient management. We aimed to assess the percentage of thyroid fine-needle aspiration biopsies (FNABs) with AUS/FLUS diagnoses in different North American and European practice settings (e.g. community, academic, etc.), assess whether patients were managed according to current guidelines, and determine patient outcomes. MATERIALS AND

methodsA detailed questionnaire survey was posted in secure websites used separately by cytopathologists and cytotechnologists. The questionnaire was posted from August 1 through December 31, 2013.

resultsEndocrinologists and cytopathologists performed 51.7% and 37.1% of thyroid FNABs, respectively. The Bethesda reporting system for thyroid FNAB was used in 90% of practices. The rate of AUS/FLUS varied widely among institutions, with 46.1% of represented institutions reporting AUS/FLUS rates of 3-10%. The median follow-up rate of patients with an initial AUS/FLUS diagnosis was 70% (range, 10-100%). For the majority of represented institutions (86.4%), patients with initial AUS/FLUS diagnosis had follow-up with endocrinologists. Of repeat AUS/FLUS thyroid FNABs, a median of 52% was considered benign, and 18% were suspicious of or positive for malignancy (median, 10% and 7.5%, respectively).

conclusionsReporting of the AUS/FLUS category varied widely among different institutions. The median follow-up rate was lower than published guidelines. The most common follow-up diagnosis was benign thyroid nodule. Improved standardization of cytologic criteria should be adopted to reduce such variation.