Follicular nodules (THY3) of the thyroid: we recommend surgery

To determine the need of total thyrodectomy for patients with follicular nodules of thyroid.

From January 2005 through June 2008, 2249 consecutive patients (438 males, 1811 females; mean age 54 yr, range 9-87) with thyroid nodules were submitted to 2518 ultrasound-guided fine-needle aspiration (USgFNA) for cytological examination. USgFNA were performed by experienced surgeon (RP) and endocrinologist (RGG) under ultra- sonographyc guidance, using a 10-MHz linear transducer. Liquid-based cytology was used.

All cytological samples were classified in 5 diagnostic classes (THY1, THY2, THY3, THY4, THY5) in agreement with the British Thyroid Association (BTA); 1.4% specimen were classified as THY5, 2.1% as THY4, 7.6% as THY3, 79.5% as THY2 and 9.4% as THY1. In 97% of THY5 patients, malignancy was found. Among THY4 patients, 95.5% were positive for thyroid tumor. Among THY3 patients, malignancy was found in 29.1%. THY3 patients with thyroid tumors were younger than those with benign lesions (46 ± 14.1 yr vs 50 ± 13.8 yr; p<0.05, t test). No statistical difference was found neither in malignancy frequency among men and women nor in mean size of nodules (24 ± 11.8 mm malignant vs 23 ± 9.4 mm benign).

this study provides evidence that USgFNA offers a very sensitive and accurate method in reducing THY1 samples and in detecting malignancy (>95% both in THY5 and THY4, and >29% in THY3 lesions). Our proposal is to submit to total thyroidectomy all patients with THY5 and THY4 lesions and THY3 thyroid nodule >1 cm.