From the Guidelines
Thyroid nodules should be monitored with ultrasound every 3 years if the initial ultrasound is normal, starting at 8 years of age, as recommended by the most recent guidelines 1. The frequency of thyroid nodule monitoring with ultrasound is crucial for early detection and management of potential thyroid cancers.
- For individuals with a history of chemotherapy or radiation exposure, consideration should be given to annual US for at least the first 5 years following completion of thyroid cancer-directed treatment 1.
- The monitoring schedule may vary depending on the nodule's risk classification and patient history, but the general recommendation is to start ultrasound surveillance at 8 years of age and repeat every 3 years if no nodules are detected 1.
- It is essential to note that benign thyroid nodules are common, and most DICER1-related thyroid cancers are indolent, with a low incidence of extrathyroidal metastasis 1.
- Factors that may necessitate more frequent monitoring include rapid growth, development of suspicious features, or high-risk patient history such as radiation exposure or family history of thyroid cancer.
- History and physical examination, including neck palpation and neurologic exam, should be performed at least annually and at each clinical opportunity 1.
From the Research
Monitoring Thyroid Nodules with Ultrasound
- The frequency of monitoring thyroid nodules with ultrasound depends on various factors, including the size and characteristics of the nodule, as well as the patient's overall health and risk factors 2, 3, 4, 5.
- Studies have shown that most benign thyroid nodules remain stable over time, with only a small percentage showing significant growth or changes in characteristics 4, 5.
- The American Thyroid Association recommends monitoring thyroid nodules with ultrasound at regular intervals, typically every 6-12 months for nodules with suspicious characteristics, and every 1-2 years for nodules with benign characteristics 2, 3.
- A study published in 2021 recommended ultrasound examination at a distance of 2 and 5 years following cytological evaluation, then every 4-5 years from then on 4.
- Another study found that malignant nodules tend to grow faster than benign nodules, with a growth rate of >2 mm/y being a predictor of malignancy 5.
- Ultrasound-guided fine needle aspiration biopsy (FNAB) is a useful tool in the management of thyroid disease, particularly for nodules that are difficult to palpate or nonpalpable 6.
Factors Influencing Monitoring Frequency
- Nodule size: Larger nodules may require more frequent monitoring, as they are more likely to be malignant 2, 3.
- Nodule characteristics: Nodules with suspicious characteristics, such as irregular margins or microcalcifications, may require more frequent monitoring 2, 3.
- Patient's overall health and risk factors: Patients with a history of thyroid cancer or other risk factors may require more frequent monitoring 2, 3.
- Growth rate: Nodules with a rapid growth rate may require more frequent monitoring, as they are more likely to be malignant 5.