Endocrine Abstracts

1500 euthyroid patients (1302 females and 198 males, mean age 47.8) presenting with thyroid enlargement were evaluated by fine needle aspiration (FNAC) of the thyroid as the first line investigation. The final cytological or histological diagnosis was determined after surgery (n=556) or clinical follow-up for a minimum period of 2 years (mean 9.5 yrs, range 2-19 years). Goitre type was assessed clinically and classified as diffuse in 184, multinodular in 457 or solitary nodule in 859 cases. The overall sensitivity and specificity of FNAC in the detection of thyroid malignancy was 82% and 88% respectively. Males presenting with thyroid enlargement had significantly higher rates of malignancy (12.6% versus 7.2%, P=0.009) and neoplasia (benign + malignant, 20.2% versus 12.7%, P=0.005) than females. Significantly higher rates of neoplasia (P=0.01) were detected in patients less than 30 years (20.5%, n=190) and in those aged over 60 (14%, n=372), when compared with patients aged 30-60 (12.2%, n=938). Non-significantly higher rates of malignancy were detected in younger and older age groups when compared to those aged 30-60. Subjects presenting with solitary nodules had significantly higher rates of both malignancy (10.6% versus 4.4%, P<0.001) and neoplasia (18% versus 8.0%, P<0.001) when compared with patients exhibiting diffuse or multinodular goitres. 836 patients within the cohort had serum TSH measured in a sensitive assay at presentation. Subjects with a normal (0.4-5.5mU/l, n=689) or raised TSH (>5.5mU/l, n=19) had significantly increased risks of thyroid malignancy (9.1% and 31.6%, P<0.001) and neoplasia (16.9% and 42.1%, P<0.001) when compared with those with low (<0.4mU/l) TSH (malignancy 4.7% and neoplasia 5.5% respectively).

We confirmed FNAC to be an accurate test in the detection of thyroid neoplasia in a large UK cohort of patients. Age, gender, goitre type and TSH level at presentation, all contribute significantly to the prediction of thyroid neoplasia and malignancy.