From the Guidelines
I strongly recommend scheduling a dedicated thyroid ultrasound to further evaluate the 1.8 cm hypoattenuating right thyroid nodule found on your CT chest, as it meets the American College of Radiology (ACR) criteria for additional assessment. This follow-up is necessary to provide more detailed information about the nodule's characteristics, including whether it is solid or fluid-filled, its exact size, blood flow patterns, and features that might suggest benign or potentially concerning properties 1.
Importance of Ultrasound Evaluation
The ultrasound evaluation is crucial in assessing the risk of malignancy in thyroid nodules. According to the ACR Appropriateness Criteria, thyroid nodules larger than 1 cm should be evaluated further with ultrasound, and fine-needle aspiration (FNA) should be considered if suspicious features are present 1.
Next Steps After Ultrasound
Based on the ultrasound findings, your doctor may recommend additional steps such as fine needle aspiration (biopsy) if certain suspicious features are present, such as hypoechogenicity, microcalcifications, or irregular borders 1. The biopsy results will be categorized according to the Bethesda System for Reporting Thyroid Cytopathology, which will guide further management decisions 1.
Molecular Diagnostic Testing
Molecular diagnostic testing may also be useful in evaluating FNA samples that are indeterminate, to assist in management decisions 1. The presence of certain mutations, such as BRAF V600E, can increase the suspicion of malignancy and guide further treatment.
Conclusion and Recommendation
In summary, a dedicated thyroid ultrasound is essential for further evaluating the 1.8 cm hypoattenuating right thyroid nodule, and additional steps such as fine needle aspiration (biopsy) and molecular diagnostic testing may be necessary based on the ultrasound findings. The ultrasound should be scheduled promptly, ideally within the next few weeks, and you should bring your CT chest report to the appointment for comparison.
From the Research
Thyroid Nodule Evaluation
- The presence of a hypoattenuating right thyroid nodule measuring at least 1.8 cm warrants further evaluation with dedicated thyroid ultrasound, as it meets the ACR criteria 2, 3.
- Fine needle aspiration biopsy (FNAB) is a crucial step in the evaluation of thyroid nodules, especially those with suspicious clinical findings or ultrasound features suggestive of malignancy 2, 4, 5, 6.
Ultrasound-Guided Fine-Needle Aspiration
- Ultrasound-guided fine-needle aspiration biopsy (US-FNAB) allows for real-time visualization of the needle and is essential for lowering the yield of nondiagnostic specimens and false-negative results 2, 5.
- The use of US-guidance for FNAB is highly operator-dependent, and a standardized and meticulous technique is necessary to increase diagnostic results 2, 5.
Diagnostic Features of Thyroid Nodules
- Certain morphological sonographic features, such as microcalcifications, coarse internal calcifications, and infiltrative or microlobulated margins, are significantly more common among malignant lesions 3.
- Characteristics that are statistically significantly associated with benignity include peripheral calcification and purely cystic composition 3.
- The presence of colloid on both ultrasound and cytology may be found in malignant lesions, whereas microcalcifications can sometimes be found in benign lesions 3.