Purpose: o To assess the safety and adequacy of Core Needle Biopsy of Thyroid nodules. Materials and methods: o Retrospective study, patient radiology notes and discharge notes reviewed o Data items collected: o departmental database interrogated to collect a breakdown of all thyroid biopsies performed over time period of past 8 months. o Reviewed patient discharge notes - review details of consent, clotting documentation, procedural details including number of passes, needle type and core size, operator, right/ left lobe/isthmus. o details of post – procedural complications and final histology report. o Data analyzed and tabulated. Results: o All biopsies were done with an 18G 6cm needle with an adjustable variable (10 or 20mm)notch size. Trans-isthmic approach was used as far as possible. o Twenty-six biopsies done from 20 nodules. Nodule size ranging from 14 to 55mm. Lobar distribution as illustrated above. o Age of the patients ranged between 29-94 years with a mean age of 63 years. About 70% (n=14) patients were Female and 30%(n=6) Male. o Of the 20 patients, 9 (45%) had at least one previous inadequate FNA, 3 (15%) had no prior FNA done and 8 (40%) had a positive prior FNA. o Twenty-four (92.3%)of the 26 samples were adequate to provide a histological diagnosis. Two samples (7.7%) were inadequate/non diagnostic. o Larger nodules allowed larger and multiple cores to be obtained, multiple cores were obtained in about 20% (n=4) of patients as opposed to single cores in the remaining 80% (n=16). o The distribution of samples among the 10 vs 20mm cores was equal. The adequacy of the samples was 100% in the longer 20mm cores Vs 84.6% in the 10mm core samples. The two non diagnostic samples were both 10mm cores, further, these nodules had a more cystic component than the others. o Of the 24 adequate samples, 19 (79.2%) were benign, 3 (12.5%) were malignant, 2 (8.3%) showed follicular neoplasm, one of which was operated and confirmed Follicular carcinoma. o No Major complications were observed, 1 patient (0.05%) had a focal hematoma , managed conservatively and did not progress. Conclusions: o Thyroid CNB is a safe and rapid method to evaluate thyroid nodules. o It is especially useful for nodules with prior non-diagnostic FNA and for patients with benign nodules who want to avoid a diagnostic hemithyroidectomy. o Although its safety is well documented, No guidelines exist for Thyroid CNB as a first line in diagnosis. Dr Prashant Gupta Department Of Radiology, Scunthorpe General Hospital, Cliff Gardens, DN157BH. References: 1. Ha EJ, Baek JH, Lee JH, et al. Complications following US-guided core-needle biopsy for thyroid lesions: a retrospective study of 6,169 consecutive patients with 6,687 thyroid nodules. European radiology 2017;27:1–9. doi:10.1007/s00330-016-4461-9 2. Paja M, del Cura JL, Zabala R, et al. Ultrasound- guided core-needle biopsy in thyroid nodules. A study of 676 consecutive cases with surgical correlation. European radiology 2016;26:1–8. doi:10.1007/s00330-015-3821-1 3. Ha EJ, Baek JH, Lee JH, et al. Core needle biopsy can minimise the non-diagnostic results and need for diagnostic surgery in patients with calcified thyroid nodules. European radiology 2014;24:1403–9. doi:10.1007/s00330-014-3123- z 4. Suh, C. H., Baek, J. H., Lee, J. H., Choi, Y. J., Kim, J. K., Sung, T.-Y., … Shong, Y. K. (2016). The Role of Core-Needle Biopsy as a First-Line Diagnostic Tool for Initially Detected Thyroid Nodules. Thyroid, 26(3), 395–403. http://doi.org/10.1089/thy.2015.0404 5. Chen, B., Jain, A., Dagis, A., Chu, P., Vora, L., Maghami, E., & Salehian, B. (2015). Comparison of the Efficacy and Safety of Ultrasound-Guided Core Needle Biopsy Versus Fine-Needle Aspiration for Evaluating Thyroid Nodules. Endocrine Practice, 21(2), 128–135. http://doi.org/10.4158/EP14303.OR Adequacy and Safety of Thyroid Core Needle Biopsy (CNB)