From the Guidelines
For a thyroid nodule that was biopsied and classified as Bethesda category 2 (benign) with follow-up ultrasound at 6 months showing similar size, routine clinical surveillance is recommended, with another follow-up ultrasound in 12-24 months to ensure continued stability, as supported by the American College of Radiology guidelines 1. This approach prioritizes the patient's quality of life and minimizes unnecessary interventions, given the very low risk of malignancy (less than 3%) in Bethesda 2 nodules. The stability in size on follow-up ultrasound further confirms the benign nature of the nodule. Key considerations in managing thyroid nodules include:
- The role of imaging in diagnosing and characterizing thyroid findings, as outlined in the ACR Appropriateness Criteria for thyroid disease 1.
- The importance of molecular testing for differentiated thyroid cancer (DTC), as discussed in the NCCN Guidelines for Thyroid Carcinoma 1.
- The need for individualized management based on the type of thyroid cancer, patient factors, and clinical presentation. However, if the patient develops concerning symptoms such as difficulty swallowing, voice changes, or if the nodule significantly increases in size (generally more than 20% increase in at least two dimensions), earlier reassessment would be warranted. No medication is typically required for benign, stable thyroid nodules unless there is associated thyroid dysfunction. Overall, the management of thyroid nodules should balance the risks and benefits of intervention, prioritizing the patient's morbidity, mortality, and quality of life.
From the Research
Thyroid Nodule Biopsy Recommendations
- For thyroid nodules biopsied with a Bethesda 2 category, the recommendation is to perform a follow-up ultrasound in 6-12 months to assess for any changes in size [ 2 ].
- If the nodule size remains similar after 6 months, the risk of malignancy is relatively low, with a reported incidence of 1.53% [ 2 ].
- However, it is essential to continue monitoring the nodule with regular ultrasound follow-ups to detect any potential changes [ 3 ].
Ultrasound Follow-up Intervals
- A study published in 2018 found that repeat US-FNA for initially non-diagnostic thyroid nodules can be performed at a six-month interval after the initial procedure without tumor progression [ 3 ].
- Another study from 2022 suggested that the combined use of TIRADS and BETHESDA categories can efficiently provide accurate results for making preoperative diagnoses of thyroid nodules and determining the risk of malignancy [ 4 ].