From the Guidelines
The management of thyroid nodules based on the Thyroid Imaging, Reporting and Data System (TI-RADS) involves a risk-stratified approach that guides further evaluation and intervention, with the goal of reducing unnecessary biopsies while ensuring appropriate surveillance of potentially malignant nodules 1.
TI-RADS Categories and Management
The TI-RADS system categorizes nodules from TR1 (benign) to TR5 (high suspicion for malignancy) based on ultrasound characteristics.
- TR1 nodules generally require no further evaluation as they carry minimal risk of malignancy.
- TR2 nodules (less than 2% risk) typically need no fine needle aspiration (FNA) unless they are large.
- TR3 nodules (5% risk) warrant FNA if ≥2.5 cm or follow-up if 1.5-2.4 cm.
- TR4 nodules (5-20% risk) require FNA if ≥1.5 cm or follow-up if 1.0-1.4 cm.
- TR5 nodules (>20% risk) should undergo FNA if ≥1 cm or follow-up if 0.5-0.9 cm. This system helps balance the risk of missing clinically significant cancers against the harms of overdiagnosis and overtreatment, as noted in the ACR Appropriateness Criteria for thyroid disease 1.
Follow-up Intervals
Follow-up intervals typically range from 1-5 years depending on the TI-RADS category and nodule size, with higher risk categories requiring more frequent monitoring.
- The use of ultrasound provides high-resolution imaging to characterize the nodule for the risk of malignancy, guiding the decision to biopsy under the ACR TI-RADS and other risk stratification criteria 1. By prioritizing a risk-stratified approach based on TI-RADS, clinicians can optimize the management of thyroid nodules, minimizing unnecessary interventions while ensuring timely detection and treatment of potentially malignant lesions 1.
From the Research
TI-RADS Stage and Management
The management approach for thyroid nodules based on the Thyroid Imaging, Reporting and Data System (TI-RADS) stage involves a risk-based protocol that promotes high-quality care and minimizes cost and unnecessary testing 2. The TI-RADS system is used to stratify the risk of malignancy in thyroid nodules, with higher scores indicating a higher risk of cancer.
TI-RADS Classification
The TI-RADS classification system categorizes thyroid nodules into five categories based on their ultrasound characteristics, with scores ranging from 0 to 13 points 3. The categories are:
- TI-RADS 2: Benign (0% malignancy)
- TI-RADS 3: Low suspicion (<5% malignancy)
- TI-RADS 4: Moderate suspicion (5-80% malignancy)
- TI-RADS 5: High suspicion (>80% malignancy)
Management Approach
The management approach for thyroid nodules based on the TI-RADS stage is as follows:
- TI-RADS 2 and 3: Nodules with a low risk of malignancy can be safely managed with surveillance, and fine-needle aspiration biopsy (FNAB) is not recommended 4, 5.
- TI-RADS 4 and 5: Nodules with a moderate to high risk of malignancy should undergo FNAB to determine the presence of cancer, and surgery may be recommended if cancer is diagnosed 4, 5.
- TI-RADS 4: Nodules with a moderate suspicion of malignancy may undergo molecular testing to further evaluate the risk of cancer 2.
Key Points
- The TI-RADS system is a useful tool for stratifying the risk of malignancy in thyroid nodules and guiding management decisions.
- The management approach for thyroid nodules based on the TI-RADS stage involves a risk-based protocol that promotes high-quality care and minimizes cost and unnecessary testing.
- FNAB and molecular testing may be recommended for nodules with a moderate to high risk of malignancy to determine the presence of cancer and guide treatment decisions.