Analysis of patients with Thy3 cytology in a DGH setting: 2013-2014

P Machenahalli, F Kubba, K Baynes, Ealing Hospital.

Introduction: 4-7% of the adult population have a palpable thyroid nodule and more nodules are detected by ultrasound. FNAC is the gold standard method used for investigation of thyroid nodules. The British Thyroid Association introduced the Thy classification in 2014 with the aim of standardising patient pathways. Previous studies have suggested that cytological criteria of thy 2 (benign) to thy 5 (malignant) are reliable when reported by experienced pathologists.

Aim: To assess cytological, radiological and biochemical investigations of thyroid nodules and analyse the histological grading of thyroid nodules selected for surgery.

Patients and methods: Retrospective review of 25 patients with a 26 cytologically graded Thy3 thyroid nodule. Of these 18 had a surgery, 3 are under follow up, 1 has lost follow, 3 referred to a tertiary centre.

Results: Patientsí age range was 20-80 years. 76% were female (n=20).† 100% of patients had thyroid function tests prior to FNA; 84% were biochemically euthyroid.† Mean size of the dominant nodule was 4cm (range 1.0-9.5cm). 15% had inadequate sampling (Thy1) before a Thy3 grading sample was obtained. Post-operative cytology showed evidence of thyroid carcinoma in 15% (4/26). Malignant nodules ranged in size between 3-9 cm. All four thyroid carcinoma patients were over 40 years old and had nodules >2cm in diameter.

Conclusion:†† In the above analytical study, one in 6.5 thyroid nodules with thy3 cytology had thyroid malignancy with equal sex distribution. A previous study indicates the incidence of 1 malignancy per 4-5 thy3 nodules. Our study may be limited by the sample size. Only 16% of these patients had total thyroidectomy, recent studies have suggested that total thyroidectomy has better outcome for follicular thy3 nodules, this area is still debatable as patient ends on lifelong thyroxin following total thyroidectomy and unnecessary surgery for the innocent nodules.


  1. Thyroid. 2009 Jan;19(1):33-7. doi: 10.1089/thy.2008.0200 JCEM
  2. CalÚ et al. BMC Surgery 2014, 14:12 http://www.biomedcentral.com/1471-2482/14/12

1.    BTA guidelines 2014