A threshold value in Shear Wave elastography to rule out malignant thyroid nodules: a reality?

Area of Science:

• Medical Imaging
• Oncology
• Endocrinology

Background:

• Thyroid nodules are common, with malignancy detection crucial for patient management.
• Standard ultrasound relies on morphological signs, which can be subjective.
• Elastography offers a quantitative method to assess tissue stiffness.

Purpose of the Study:

• To determine the efficacy of a Shear Wave elastography threshold for excluding malignant thyroid nodules.
• To assess the added value of elastography combined with morphological ultrasound signs.

Main Methods:

• 151 thyroid nodules from 148 patients undergoing surgery were analyzed using standard ultrasound and Shear Wave elastography.
• Morphological signs and elastographic index were correlated with histological findings.
• A double-blind study design was employed.

Main Results:

• Malignant nodules exhibited significantly higher elastographic indices (115 kPa) than benign nodules (41 kPa).
• A 66 kPa threshold demonstrated 80% sensitivity and 90.5% specificity for malignancy.
• The combination of elastography and morphological signs achieved 97% sensitivity and 99.5% negative predictive value.

Conclusions:

• Shear Wave elastography, with a 66 kPa threshold, is a reliable ultrasound marker for ruling out malignant thyroid nodules.
• This quantitative and reproducible method is effective for nodules >3 cm.
• Further research is needed for calcified nodules and follicular tumors.