Endocrine Abstracts

Background: Thyroid nodules are the most common thyroid disease. In the majority of cases, they are benign. However, 5 to 15% of nodules are cancer. The aim of our study was to determine the clinical and biological predictive factors of malignancy in thyroid nodules.

Methods: We performed a retrospective descriptive study including 100 patients collected in the endocrinology department of La Rabta hospital over 18 year old period (2000–2018). All these patients underwent thyroidectomy for one or more suspicious thyroid nodules on clinical, ultrasound or cytological criteria. For each patient, the epidemiological, clinical and biological data and the histological result of the surgical specimen were collected. Predictive factors of malignancy were determined by the calculation of Odds Ratios.

Results: The average age of our patients was 49.9±17.4 years and the sex ratio (F/M) was 6.69. The prevalence of malignant nodules was 20%. It was of 22% in women and 8% in men (P=0.4). Multiple nodule were more likely to be associated with benign nodules (OR=0.2; P=0.004). The clinical predictors of malignancy were a right sided nodule (OR=3; P=0.03), an upper sided nodule (OR=20; P< 0.001), the hard consistency (OR=15.5; P < 0.001) and the fixed nodule (OR=21; P < 0.001). As for biochemical characteristics, there were no significant difference concerning thyroid stimulating hormone (TSH), FT4, calcium level and parathyroid hormone between benign and malignant thyroid nodules. However, hyperthyroidism was significantly associated with benignancy (OR=0.1; P=0.01). Primary hyperparathyroidism was more frequent with malignant nodules (20%). However, the association was not statistically significant.

Conclusion: Our study shows that the evaluation of thyroid nodules needs a careful study of all its clinical and biochemical characteristics.