SAT-LB100 Suspicious Thyroid Nodules: Management Since the Introduction of 2015 ATA Guidelines

Objective: In 2015, updated American Thyroid Association (ATA) guidelines recommended observation for suspicious sub-centimeter thyroid nodules based on their indolent course. Evaluation of individual patient factors and nodule invasiveness should guide clinician decision-making about biopsy. We aimed to evaluate frequency of biopsy in suspicious thyroid nodules since the introduction of these guidelines, including factors contributing to clinical decision making in a tertiary care center. Methods: Retrospective study of patients in a tertiary medical center with new, suspicious thyroid nodules between March 1, 2015, and July 1, 2017. We identified suspicious nodules ≤ 1 cm, not previously biopsied. Suspicious nodules were defined as those 1) mentioned suspicious by radiology, 2) hypoechoic nodules with ≥ 1 worrisome feature mentioned by radiology, or 3) with worrisome neck lymph nodes. Results/Discussion: We identified a total of 138 nodules in 127 patients: mean age 58.2 ± 14.2, 73% female, 87% Caucasian, and mean Charlton Comorbidity Index 2.4 ± 2.3, corresponding with 77-90% 10 year survival. Thyroid nodule characteristics included 88% hypoechoic, 47% micro-calcifications, 28% irregular margins, and 26% peripheral calcifications; 57% were located ≤1 mm from thyroid edge. Frequency of biopsy in suspicious thyroid nodules was 38%. Ultrasound features associated with increased likelihood of biopsy included larger nodule volume (0.18 vs 0.13cm(3), p=0.01) and presence of concerning lymph nodes (69% vs 31%, p<0.01). Patient’s age and degree of comorbidities did not change likelihood for biopsy. Frequency of biopsy did not vary by type of provider (endocrinologist vs other) or trigger for thyroid nodule diagnosis (incidental vs. non incidental). Among 85 nodules that were not biopsied, 41% did not have specific recommendation for follow-up, and the remainder were recommended for follow-up ultrasounds in 3-6 months (19%), 7-12 months (19%), and >12 months 21%. Only one quarter of those who were recommended repeat ultrasound had documented re-evaluation. Conclusion: One third of suspicious thyroid nodules underwent biopsy since release of updated ATA guidelines. Factors driving thyroid biopsy seems to be associated with nodule characteristics but not with patient’s factors including age and comorbidities. Patients who did not have biopsy had inconsistent follow up regimens, and many did not have any follow up plan. Further studies and development of decision aides may be helpful in providing an individualized approach for suspicious thyroid nodules. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.