Diagnostic Value of Fine Needle Aspiration in Diagnosis of Thyroid Nodules at the Endocrine Clinic of Hamadan City During a 10-Year Period, Iran.

BACKGROUND

Thyroid nodules are common endocrine disorders. Most nodules are benign, with only 5% to 15% being malignant. Fine needle aspiration (FNA) is a primary diagnostic method; however, recent studies have raised concerns about its diagnostic reliability. This study aimed to evaluate performance of FNA in diagnosing thyroid nodules using pathology results as the gold standard. A cross-sectional study.

METHODS

This study analyzed patients who were referred to an endocrine clinic in Hamadan city and underwent thyroidectomy during a 10-year period. The collected data included demographics, clinical symptoms, FNA results, and pathological outcomes. Statistical analysis was conducted using Stata software, with the significance level set at 0.05.

RESULTS

The study included 700 patients, predominantly female (86.2%), with a mean age of 42.5 years. FNA results were as follows: non-diagnostic in 4.8% (n=43), benign in 43.4% (n=304), atypia of undetermined significance or follicular lesion of undetermined significance in 6.1% (n=42), follicular neoplasm in 13.2% (n=92), suspicious for malignancy in 22.8% (n=160), and malignant nodules in 9.7% (n=68) of the cases. Pathology revealed malignant nodules in 56.9% (n=398) of the cases, predominantly papillary carcinoma. Significant factors associated with malignancy included younger age, male gender, history of thyroid cancer in a first-degree relative, and the presence of cervical adenopathy. FNA showed a sensitivity of 72.43% (95% CI 67.58%, 76.93%) and a specificity of 89.64% (95% CI 85.46%, 92.95%), with an accuracy of 79.85% (95% CI 76.55%, 82.87%).

CONCLUSION

While FNA is a valuable diagnostic tool for thyroid nodules, its sensitivity varies, necessitating close follow-up of patients with negative results.