From the Guidelines
For a thyroid nodule with Bethesda category III and a cancer risk of approximately 4%, the recommended approach is typically repeat fine needle aspiration (FNA) after 3-6 months or molecular testing of the initial FNA sample. This approach is supported by recent guidelines and studies, including those published in 2025 1. The management of thyroid nodules with a low cancer risk, such as in this case, should prioritize a balanced approach that considers the potential benefits and harms of different management strategies.
Key Considerations
- The cancer risk of 4% is relatively low, which justifies a more conservative approach rather than immediate surgery.
- Repeat FNA or molecular testing can help clarify the diagnosis and reduce the risk of unnecessary surgery.
- Surgical consultation for possible diagnostic lobectomy may be considered for nodules larger than 2 cm or those with suspicious ultrasound features.
- Active surveillance with regular ultrasound monitoring every 6-12 months is a reasonable option for smaller nodules without concerning features.
Individualized Management
The management decision should be individualized based on patient factors, including:
- Age
- Comorbidities
- Nodule size
- Ultrasound characteristics
- Patient preference This approach ensures that the management strategy is tailored to the individual patient's needs and priorities, while also minimizing the risk of unnecessary surgery or other interventions. As noted in recent studies, the interpretation and application of guidelines in clinical practice can be challenging, and coordinated guidelines are needed to ensure consistent and effective management of thyroid nodules 1.
From the Research
Recommended Treatment for Thyroid Nodule with Bethesda Category III
The recommended treatment for a thyroid nodule with a Bethesda category III cancer risk of 4% is not explicitly stated in the provided studies. However, the following points can be considered:
- Fine-needle aspiration (FNA) is the most dependable tool to triage thyroid nodules for medical or surgical management 2.
- Ultrasound (US) has a high efficacy in diagnosing thyroid nodules and can be helpful in differentiating benign and malignant Bethesda class III thyroid nodules 2.
- The malignancy risk of thyroid nodules reported as Bethesda category III (AUS/FLUS) on initial FNA is still controversial among different studies 3.
- Independent malignant risk factors in patients with thyroid nodule classified as Bethesda category III include microcalcification, shape, diameters, anti-thyroglobulin antibodies (TGAb), anti-thyroid peroxidase antibody (A-TPO), and nodule goiter 3.
- The American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) can be used to classify thyroid nodules and predict malignancy 4.
Diagnostic Approaches
Some diagnostic approaches that can be considered for thyroid nodules with Bethesda category III include:
- Repeat FNA 5
- Surgical excision 3, 4, 5
- Molecular assays, such as gene expression assays using FNA material 6
- Ultrasound features, such as echogenicity, echogenic foci, and shape 2, 4
Malignancy Rates
The malignancy rates for Bethesda category III thyroid nodules vary among studies, ranging from 10 to 30% 5, 6. The malignancy rate in one study was found to be 26.6-37.8% 5, while another study reported a malignancy rate of 25% for category III 6.