Endocrine Abstracts

Background: Thyroid malignancy is the sixth common cancer type in the United Arab Emirates (UAE) where its incidence is increasing worldwide. There are no epidemiological data outlining the prevalence of cancer in thyroid nodules, nor previous analysis of ultrasonographic features correlating with thyroid malignancy in the UAE.

Aim: To report the prevalence of thyroid malignancy in thyroid nodules and correlate it with demographic data. A secondary aim is to define some ultrasonographic features that could predict thyroid malignancy.

Methods: Retrospective electronic medical records review of patients with thyroid nodules aged 18–80 years with a normal TSH who underwent ultrasound guided fine needle aspiration biopsy (UG-FNA) at Sheikh Khalifa Medical City (SKMC) during 2011–2015.

Results: A total of 573 nodules with normal Thyroid Stimulating Hormone (TSH) underwent UG-FNA cytological examination. Nodules were more frequent in females (59.2%) between 30–49 years of age and in males, (48.4%) between 40–59 years of age. The overall crude prevalence of thyroid cancer in thyroid nodules was 8.8% (95% Confidence Interval (CI) 6.5%–11.2%). The prevalence was 8.3% (95% CI 5.8–10.8) in females and 11.9% (95% CI 5.0–18.8) in males. The prevalence among UAE nationals, Arabs, and Far East Asians was 8%, 9.5% and 13.3% respectively. Classical papillary thyroid cancer was found in 46.9% of all cancerous nodules. Of all malignant nodules, 36.2% were complex and 36.2% were of hypoechoic echogenicity. 41.7% of cancerous nodules were between 2–4 cm size.

Conclusion: Cancer rate was higher in males (11.9%) compared to that in females (8.3%). Among the heterogenous population in the UAE, East Asians had the highest prevalence malignancy in examined thyroid nosules. The most common histological type is papillary thyroid cancer. Ultrasonographic features associated with malignancy are nodular size between 2–4 cm and echogenicity of either hypoechoic or complex.