Utility of thyroid aspiration biopsy

Area of Science:

• Endocrinology
• Oncology
• Surgical Pathology

Background:

• Thyroid nodules are common, and accurate diagnosis is crucial for appropriate management.
• Fine-needle aspiration biopsy (FNAB) is a primary diagnostic tool for thyroid nodules.
• Evaluating the diagnostic performance of FNAB is essential for clinical decision-making.

Purpose of the Study:

• To assess the diagnostic utility and performance metrics of fine-needle aspiration biopsy in detecting thyroid carcinoma.
• To compare the accuracy, sensitivity, and specificity of FNAB based on different interpretation criteria.

Main Methods:

• A decision-analysis approach was used to evaluate FNAB in 102 patients with thyroid nodules.
• Cytologic diagnoses were categorized, and follow-up, including thyroidectomy, was performed.
• Diagnostic performance metrics (sensitivity, specificity, predictive values, accuracy) were calculated using two distinct interpretation criteria.

Main Results:

• FNAB demonstrated no morbidity. Accuracy was highest (88%) when atypical results were not considered malignant (Criterion II).
• Sensitivity was 70% and specificity 90% under Criterion II.
• Negative predictive values were high (96-99%), while positive predictive values remained low (31-44%) regardless of the criterion used.

Conclusions:

• The sensitivity and specificity of FNAB for thyroid carcinoma detection are dependent on the interpretation criteria applied.
• FNAB is a valuable tool for thyroid nodule evaluation, particularly for excluding malignancy, when interpreted alongside clinical findings.
• Optimizing interpretation criteria enhances the diagnostic accuracy of FNAB in thyroid cancer detection.