Distinguishing mummified thyroid nodules from malignant thyroid nodules.

Area of Science:

• Radiology
• Endocrinology
• Oncology

Background:

• Thyroid nodules are common, with malignancy being a primary concern.
• Accurate differentiation between benign and malignant nodules is crucial for patient management.
• Distinguishing
• mummified
• thyroid nodules from malignant ones can be challenging with conventional imaging.

Purpose of the Study:

• To identify ultrasonographic (US) features that differentiate "mummified" thyroid nodules from malignant thyroid nodules.
• To improve the accuracy of imaging-based diagnosis for thyroid nodules.
• To reduce the need for unnecessary fine-needle aspiration cytology (FNAC) biopsies.

Main Methods:

• Retrospective review of US features in 193 confirmed "mummified" thyroid nodules and 109 malignant thyroid lesions.
• Analysis of US characteristics including content, echo, shape, margin, microcalcification, lymph nodes, and specific signs.
• Evaluation of nodule changes during follow-up imaging.

Main Results:

• The cystic wall shrinkage sign and concentric configuration or finger sign were highly specific for "mummified" thyroid nodules.
• These signs demonstrated high specificity (91.7% and 99.9%) in distinguishing "mummified" from malignant nodules.
• A continuous decrease in cyst size was observed in "mummified" nodules during follow-up.

Conclusions:

• "Mummified" thyroid nodules exhibit characteristic US features: cystic wall shrinkage sign and concentric configuration or finger sign.
• These US findings, along with size reduction over time, aid in differentiating "mummified" from malignant thyroid nodules.
• Ultrasonography can facilitate accurate imaging-based differential diagnosis, potentially reducing invasive procedures.