DIAGNOSTIC ACCURACY OF ULTRASOUND IN CHARACTERIZATION OF THYROID NODULES ON THE BASIS OF TIRADS CLASSIFICATION KEEPING FNAC AS GOLD STANDARD

Abstract

Background: Thyroid nodules are increasingly common and pose a diagnostic challenge, particularly in distinguishing benign from malignant lesions. In low-resource settings like Pakistan, effective and accessible diagnostic tools are essential to guide appropriate clinical management and avoid unnecessary invasive procedures. The Thyroid Imaging Reporting and Data System (TIRADS) offers a standardized ultrasonographic approach for risk stratification of thyroid nodules. However, its validation in local populations remains limited.

Objective: To assess the diagnostic performance of TIRADS in differentiating benign and malignant thyroid nodules in a Pakistani population, using fine-needle aspiration cytology (FNAC) as the reference standard.

Methods: A cross-sectional validation study was conducted at Jinnah Postgraduate Medical Centre, Karachi, from April to September 2024. A total of 100 patients with thyroid nodules were enrolled. Ultrasound examinations were performed by an experienced radiologist using a 7–15 MHz transducer. Nodules were categorized according to TIRADS, and all participants underwent FNAC for histological confirmation. Diagnostic metrics—sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy—were calculated. Stratified analysis was conducted based on gender, age, location, and thyroid function status.

Results: The mean age of participants was 46.91 ± 18.25 years, with a slight female predominance (56%). Malignancy was identified in 64% of cases on ultrasound and 78% on FNAC. TIRADS demonstrated 80.8% sensitivity, 95.5% specificity, 98.4% PPV, 58.3% NPV, and 84.0% overall accuracy. TIRADS 5 was the most frequent category (24%). Higher sensitivity was noted among rural residents (85.7%) and females (84.1%), while specificity declined in patients over 60 years (80%).

Conclusion: TIRADS offers high diagnostic accuracy in confirming thyroid malignancy and is a valuable triage tool in resource-limited settings. However, its limited NPV warrants cautious interpretation of low-risk classifications. Local validation and radiologist training are essential for optimized use.

Background: Thyroid nodules are increasingly common and pose a diagnostic challenge, particularly in distinguishing benign from malignant lesions. In low-resource settings like Pakistan, effective and accessible diagnostic tools are essential to guide appropriate clinical management and avoid unnecessary invasive procedures. The Thyroid Imaging Reporting and Data System (TIRADS) offers a standardized ultrasonographic approach for risk stratification of thyroid nodules. However, its validation in local populations remains limited.

Objective: To assess the diagnostic performance of TIRADS in differentiating benign and malignant thyroid nodules in a Pakistani population, using fine-needle aspiration cytology (FNAC) as the reference standard.

Methods: A cross-sectional validation study was conducted at Jinnah Postgraduate Medical Centre, Karachi, from April to September 2024. A total of 100 patients with thyroid nodules were enrolled. Ultrasound examinations were performed by an experienced radiologist using a 7–15 MHz transducer. Nodules were categorized according to TIRADS, and all participants underwent FNAC for histological confirmation. Diagnostic metrics—sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy—were calculated. Stratified analysis was conducted based on gender, age, location, and thyroid function status.

Results: The mean age of participants was 46.91 ± 18.25 years, with a slight female predominance (56%). Malignancy was identified in 64% of cases on ultrasound and 78% on FNAC. TIRADS demonstrated 80.8% sensitivity, 95.5% specificity, 98.4% PPV, 58.3% NPV, and 84.0% overall accuracy. TIRADS 5 was the most frequent category (24%). Higher sensitivity was noted among rural residents (85.7%) and females (84.1%), while specificity declined in patients over 60 years (80%).

Conclusion: TIRADS offers high diagnostic accuracy in confirming thyroid malignancy and is a valuable triage tool in resource-limited settings. However, its limited NPV warrants cautious interpretation of low-risk classifications. Local validation and radiologist training are essential for optimized use.