Endocrine Abstracts

Introduction: In 2004, the multidisciplinary thyroid nodule committee of our centre adopted the cytological classification from the British Thyroid Association for reporting fine-needle aspiration biopsy (FNAB) results and agreed about its proper management: Thy1, inadequate sample, repeat FNAB. Thy2, benign; follow up, repeat FNAB if nodule growth; Thy3 indeterminate or follicular lesions; surgery or repeat FNAB at 6 months if low clinical, sonographic or cytologyc suspicious; Thy4, suspicious and Thy5, malignant; surgery.

Aim: To assess the role of repeating FNAB in the evaluation of thyroid nodules initially classified as benign (Thy2) or indeterminate (Thy3).

Results: We reviewed a cohort of 149 patients: 108 classified as benign nodule (Thy2) and 41 as follicular lesion (Thy3) over a 5 years period (2004–08). Repeat FNAB under ultrasound guidance was performed in all patients. Surgical pathology results were available in 44 patients.

Among 108 Thy2-patients, 93 continue as Thy2 (86%): 23 (25%) have undergone surgery: 21 adenomatosus nodules and 2 follicular adenomas. Fifteen patients (14%) change to Thy3: 8 have had surgical excision: 1 adenomatosus nodule with a papillary carcinoma focus, 1 follicular adenoma and 6 adenomatosus nodules.

Among 41 Thy3-patients, 30 change to Thy2 (73%): 3 have been operated, all without neoplasia. Eleven patients (27%) maintain the Thy3 score or change to Thy4: All have been managed with surgery except one patient who refused: 2 follicular adenomas (20%), 2 papillary carcinomas (20%), and 6 non-neoplastic results (60%).

Conclusions: Repeat FNAB in thyroid nodules diagnosed as thy3, could avoid surgery in 70% of cases if there is no clinical or sonographic suspicious. This approach could delay surgery in less than 5% of patients with malignancy. Repeat FNAB for growting thyroid nodules, when the initial diagnosis is thy2, is not useful and only rare cases of adenomatosus nodules with carcinoma focus, could be missed.