Endocrine Abstracts

Introduction: Fine needle aspiration cytology (FNAC) is a valuable and cost-effective pre-operative investigation for thyroid nodules. The British thyroid association (BTA) previously recommended two non-neoplastic results 3–6 months apart in aspirates to exclude neoplasia¹. However, in recently updated BTA guidelines, repeat aspirates were recommended when there are clinical or ultrasound suspicions².

Aim: The aim of our study was to investigate whether one multidisciplinary benign FNA cytology can sufficiently out rule malignancy in all cases.

Methods: The cytological diagnoses of all thyroid FNA biopsies performed during the 5 years period (2008–2012) were retrieved retrospectively from the pathology laboratory information system.

Results: Five hundred and sixty seven thyroid FNAs were performed on 433 patients between 2008 and 2012. 424 (74.8%) showed benign cytology (Thy2). 41% of these cases (n=123) had a repeat FNA in 3–6 month according to previous BTA guidelines. Of initial Thy2 cytology, 108 (87.8%) remained Thy2 on follow-up aspirates, 3 (2.4%) showed Thy3 features, and 10 (8.1%) were non diagnostic (Thy1). 40 cases with initial Thy2 cytology underwent thyroidectomy for either an intermediate (Thy3) result on follow-up aspirate or due to compressive symptoms. Benign thyroid disease was confirmed in 34 (85%) cases and in the remainder six cases (15%) the histology revealed follicular adenoma. No malignant cases were found on final histology.

Conclusion: One multidisciplinary benign FNA aspirate is sufficient to out rule malignancy in most cases of Thy2 cytology. A repeat FNA should only be performed if there are remaining clinical and/or radiological concerns.

References: 1. British Thyroid Association (2007) Royal College of Physicians: BTA Guidelines for the management of thyroid cancer. 2nd edition. Internet: (http://www.british-thyroid-association.org/Guidelines/).

2. Peros P, et al. Guidelines for the management of thyroid cancer. Clinical Endocrinology, 2014; 81: 1–122.