How Accurate is the TIRADS Test?

For the reason of thyroid nodules becoming increasingly discovered in individuals via medical imaging, it’s inevitably crucial to identify and evaluate them for potential malignancies.

Thyroid nodules form lumps or growths within the thyroid gland in the neck, and come with a growing need to pinpoint and make use of a reliable ultrasound categorization to help put thyroid nodules into a rating that classifies benign and malignant lesions with a reasonable level of certainty.

In the evaluation of thyroid nodules, fine-needle aspiration cytology (FNAC) is a crucial mainstay, although it can be mildly distressing and a number of it can become unnecessarily invasive. This is why a number of studies proposed a thyroid imaging reporting and data system (TIRADS).

The TIRADS utilizes a significant number of parameters for quantitative analysis of sonographic features, this of which the interpretation of its parameters differ in each reported study.

In TIRADS, points are allocated to several ultrasound features in a thyroid nodule and even more points are given to nodules with more suspicious features. The total points in each reported study now ascertain the nodule’s stage which basically ranges from TR1 to TR5.

As you read on this article, you’ll be getting more understanding as regards the accuracy of this rating system called TIRADS, its benefits as well as its limitations.

Key Takeaway:

• High Accuracy for Risk Assessment: TIRADS (Thyroid Imaging Reporting and Data System) effectively classifies thyroid nodules based on ultrasound features, offering reliable risk stratification for malignancy.
• Standardized Scoring System: Provides a consistent method for evaluating nodules, reducing variability among radiologists.
• Limits False Positives and Negatives: Helps minimize unnecessary biopsies for low-risk nodules while ensuring high-risk nodules are identified for further testing.
• Not a Diagnostic Tool Alone: TIRADS assesses malignancy risk but requires follow-up procedures like fine needle aspiration (FNA) for a definitive diagnosis.
• Dependent on Operator Expertise: Accuracy can vary based on the skill and experience of the technician or radiologist conducting the test.
• For more information, check here and here.

 How Accurate is the TIRADS Test?

TIRADS test works with several features as observed in ultrasound imaging in classifying nodules into its five levels categorization. These features include margins, composition, presence of echogenic foci, shape and echogenicity.

The accuracy of the TIRADS test is also measured on different parameters that include its sensitivity, specificity, and overall diagnostic performance. These parameters hugely contribute to the accuracy of the TIRADS test.

The ‘sensitivity’ as a parameter for testing the accuracy of the TIRADS test refers to the test’s ability to adequately pinpoint malignant nodules. Most especially in the thyroid category 4 and 5, TIRADS test has displayed a very high sensitivity in appropriately pinpointing nodules that requires further evaluation.

The ‘specificity’ as another parameter for testing the accuracy of the TIRADS test refers to the test’s ability to adequately pinpoint benign nodules. The TIRADS test is carried out in order to reduce false positives, lessening unwarranted biopsies especially for those nodules in thyroid category 1 and 2.

Meanwhile, one very major benefit of TIRADS is its ability to create a reasonable level of standardization especially among different radiologists. It creates a consistency that reduces differences in ultrasound interpretation. This TIRADS advantage is crucial in measuring its reliability and of course it’s accuracy.

Another parameter that measures the accuracy of TIRADS test is the ‘predictive value’.  High positive predictive value (PPV) signifies that a large proportion of nodules categorized as suspicious are indeed malignant while high negative predictive value (NPV) signifies that the majority of nodules categorized as benign are indeed harmless and non-cancerous.

What is the Most Accurate Tool in the Evaluation of Thyroid Nodules?

• The most accurate tool for evaluating thyroid nodules is fine needle aspiration (FNA) biopsy.
• FNA allows for the collection of nodule cells for cytological analysis, providing a definitive diagnosis of benign or malignant nodules.
• Ultrasound is also a highly effective imaging tool for risk assessment, particularly when using systems like TIRADS.

What is the Likelihood of Cancer in TIRADS?

• The likelihood of cancer varies depending on the TIRADS category:
  • TIRADS 1 (Benign): 0% risk of malignancy.
  • TIRADS 2 (Not Suspicious): <2% risk.
  • TIRADS 3 (Mildly Suspicious): 2–5% risk.
  • TIRADS 4 (Moderately Suspicious): 5–20% risk.
  • TIRADS 5 (Highly Suspicious): >20% risk.
• The system helps prioritize nodules for biopsy based on their malignancy risk.

What is the Gold Standard Test for Thyroid Nodules?

• The gold standard test for thyroid nodule evaluation is fine needle aspiration (FNA) biopsy.
• It provides a definitive diagnosis by analyzing the cells extracted from the nodule under a microscope.
• FNA is often guided by ultrasound for improved accuracy in targeting suspicious nodules.

FAQs

How Accurate is the TIRADS Test in Detecting Thyroid Cancer?

The TIRADS (Thyroid Imaging Reporting and Data System) test is highly accurate for identifying the risk of thyroid cancer. It uses ultrasound features to classify thyroid nodules into risk categories, with each category having a specific likelihood of malignancy. While it is not a diagnostic test, TIRADS is reliable for determining which nodules require further evaluation through biopsy.

Can TIRADS Replace a Biopsy for Thyroid Nodules?

No, TIRADS cannot replace a biopsy. It is a risk stratification tool that guides the need for further testing. For nodules classified as suspicious (TIRADS 4 or 5), a fine needle aspiration (FNA) biopsy is still necessary to confirm whether the nodule is benign or malignant.

Does TIRADS Help Reduce Unnecessary Biopsies?

Yes, TIRADS helps reduce unnecessary biopsies. By categorizing nodules based on their risk of malignancy, TIRADS ensures that only nodules with moderate to high risk (TIRADS 4 or 5) are recommended for biopsy, sparing low-risk nodules (TIRADS 2 or 3) from invasive procedures.

What Factors Affect the Accuracy of the TIRADS Test?

The accuracy of the TIRADS test depends on several factors, including the expertise of the radiologist performing the ultrasound, the quality of the imaging equipment, and the consistency in applying TIRADS criteria. Operator experience plays a crucial role in ensuring reliable results.

Is TIRADS a Reliable Tool for Monitoring Thyroid Nodules Over Time?

Yes, TIRADS is reliable for monitoring thyroid nodules. It can track changes in the size, structure, or characteristics of nodules over time, helping doctors determine whether further investigation or treatment is needed. However, additional testing like biopsies may still be required for suspicious changes.

Related:

1. When to Worry About Thyroid Nodules?
2. How to Shrink a Goiter Naturally
3. Exercise After Radiofrequency Ablation
4. Can You Live Without a Thyroid?
5. What Should TSH Levels Be After Thyroid Cancer?
6. How Fast Do Thyroid Nodules Grow?
7. How Do I Know If My Thyroid Nodule is Benign?
8. What Are the Symptoms of Cancerous Thyroid Nodules?
9. Is TIRADS 3 a Treatment?
10. Thyroid Ultrasound: Normal vs. Abnormal Findings
11. What Foods Reduce Thyroid Nodules?
12. What is a TIRADS Category 6?

Conclusion

Several studies had identified TIRADS as a valuable, reliable, non-invasive and practical method for assessing thyroid nodules in routine practice. It safely averts avoidable FNACs in a significant proportion of benign thyroid lesions.

However, its accuracy may be influenced by factors that include operator’s dependency and overlap of nodules in categories.

Reference

1. Chandramohan A, Khurana A, Pushpa BT, Manipadam MT, Naik D, Thomas N, Abraham D, Paul MJ. Is TIRADS a practical and accurate system for use in daily clinical practice? Indian J Radiol Imaging. 2016 Jan-Mar;26(1):145-52. doi: 10.4103/0971-3026.178367. PMID: 27081240; PMCID: PMC4813066.
2. Comparison of the diagnostic accuracy of K-TIRADS and EU-TIRADS guidelines for detection of thyroid malignancy on ultrasound. Retrieved from here
3. Anwar K, Mohammad AY, Khan S. The sensitivity of TIRADS scoring on ultrasonography in the management of thyroid nodules. Pak J Med Sci. 2023 May-Jun;39(3):870-874. doi: 10.12669/pjms.39.3.7313. PMID: 37250572; PMCID: PMC10214774.
4. Comparison of diagnostic accuracy of ACR-TIRADS, American Thyroid Association (ATA), and EU-TIRADS guidelines in detecting thyroid malignancy. Retrieved from here
5. Tom James Cawood, Georgia Rose Mackay, Penny Jane Hunt, Donal O’Shea, Stephen Skehan, Yi Ma, TIRADS Management Guidelines in the Investigation of Thyroid Nodules; Illustrating the Concerns, Costs, and Performance, Journal of the Endocrine Society, Volume 4, Issue 4, April 2020, bvaa031. Retrieved from here