Thyroid Bed Fine-Needle Aspiration: A Clinicocytologic Correlation
Laura J Adhikari, Jordan Reynolds, Sarah Jenkins, Aziza Nassar. Mayo Clinic, Rochester, MN; Cleveland Clinic, Cleveland, OH
Background: Monitoring changes in the thyroid bed (TB) is one of the clinical mainstays for surveillance of recurrent thyroid carcinoma. Fine needle aspiration (FNA) is a diagnostic tool that is commonly used to aid in the decision of further clinical treatment options and follow-up.
Design: We retrieved cases of soft tissue masses within the thyroid bed that were evaluated for recurrence between January 1, 2006 and February 1, 2011. All ultrasound-guided biopsies clinically suspected to be lymph node metastasis or had lymphocytes present on the FNA were excluded and only one FNA from each patient was included. If multiple biopsies were performed, only the positive FNA was included.
Results: 292 patients were identified for evaluation of recurrence; 250 papillary thyroid carcinoma (PTC), 15 follicular carcinoma, 21 medullary carcinoma, and 6 Hurthle cell carcinoma. For all FNAs that were clinically suspicious for recurrence the rate of positivity was 66.1% (193 patients). 14 of the 69 patients (20.3%) diagnosed with a negative FNA proceeded on to surgical resection or ethanol ablation. The average time between thyroidectomy and thyroid bed FNA was 76 months. On the subset of patients with a previous diagnosis PTC, who were diagnosed with either suspicious or positive for recurrent PTC on TBFNA; the following clinicopathologic parameters were found to be statistically significant.
|Parameter||Other (negative, non-diagnostic, atypical)||Suspicious/ Positive||Total||p-value***|
|Female||56 (81.2%)||118 (65.9%)||174 (70.2%)|
|Male||13 (18.8%)||61 (34.1%)||74 (29.8%)|
|Mean (SD) Tumor size||1.9cm (1.5)||2.7 cm (1.4)||2.4 cm (1.5)||<0.0001|
|Absent||31 (44.9%)||21 (11.7%)||52 (21.0%))|
|*Present||38 (55.1%)||158 (88.3%)||196 (79.0%)|
|Unknown or confined||53 (76.8%)||103 (57.5%)||156 (62.9%)|
|Present||16 (23.2%)||76 (42.5%)||92 (37.1%)|