Ultrasound-based diagnosis for solid thyroid nodules with the largest diameter <5 mm

Area of Science:

• Endocrinology
• Radiology
• Oncology

Background:

• Accurate diagnosis of small solid thyroid nodules (<5 mm) is challenging.
• Ultrasound (US) is a primary imaging modality for thyroid nodules.

Purpose of the Study:

• To assess the efficacy of an ultrasound (US)-based classification system for diagnosing small solid thyroid nodules.
• To compare the diagnostic performance of US with fine-needle aspiration (FNA) cytology.

Main Methods:

• Prospective classification of 406 small solid nodules in 365 patients using a five-category US system.
• Comparison of US diagnosis with histopathologic results from 145 surgically removed nodules.
• Evaluation of diagnostic accuracy, sensitivity, specificity, and positive predictive values for both US and cytology.

Main Results:

• Diagnostic accuracies of US and cytology were similar for small solid nodules.
• US diagnosis demonstrated higher sensitivity but lower specificity and positive predictive values compared to cytology.
• Histopathology confirmed various thyroid pathologies including papillary thyroid carcinoma and nodular hyperplasia.

Conclusions:

• An US-based classification system shows promise for the diagnosis and management of small solid thyroid nodules.
• US can be a valuable tool, potentially complementing cytologic diagnosis in evaluating these small lesions.