Endocrine Abstracts

Background: Thyroid fine needle aspiration cytology (FNAC) is an essential component of investigating discrete thyroid nodules. Grade THY3 Cytology implies a follicular lesion and usually requires diagnostic Hemithyroidectomy. Published data from UK suggests an incidence of malignancy in the range of 25 to 28% following Thy3 cytology. Nodular size of > 40 mm is shown to be significantly associated with increased incidence of thyroid malignancy. Aim: To assess the biochemical and radiological investigations of thyroid nodules according to current guidelines and analyse final surgical and histological outcomes, following surgery for THY3 Cytology.

Methods: Retrospective case note analysis of 69 patients (Female n=64; 92.7%) with THY3 FNA cytology between January 2006 and December 2010.

Results: In median ± SD (range) where shown. Age of cohort was 49±16.5 yrs (19 to 84). 82% of patients had thyroid function assessed before FNAC and 83.3% were biochemically euthyroid. TSH was 1.52 ± 2.92 mIU/L (< 0.01–18.1), fT3 4.7 ±0.67 pmol/L (4.3–7.0) and fT4 15.9 ± 8.6 pmol/L (10–59). Mean attempt rate of FNA before Thy3 cytology was 1.32 per patient. 21% had inadequate sampling (THY1). 1 in 6 had Ultrasound guided FNAC performed. Mean size of dominant nodule was 3.6 cm (Range 2.0–6.4) with no difference in the average size of the dominant nodule between benign (3.76 cm) and malignant (3.87 cm) nodules. All patients were seen by a MDT member but only 42% were discussed in regional thyroid MDT. 68% of patients had surgery. The prevalence of primary thyroid malignancy in the operated cohort was 22 % (n=10). Thyroid lobectomy was the dominant procedure undertaken.

Conclusion: The prevalence of thyroid malignancy is this cohort is in nearly keeping with published UK data. 12% of patients did not have thyroid function assessed pre FNA. The multidisciplinary assessment of thyroid nodules and adequate cytological studies is critical in improving diagnostic and therapeutic outcome.

Declaration of interest: There is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.

Funding: No specific grant from any funding agency in the public, commercial or not-for-profit sector.