Shear-wave elastography (SWE) boosts diagnostic accuracy when compared with ultrasound alone or ultrasound with MRI for diagnosing soft-tissue lesions initially believed to be benign, according to a study published online November 27 in Radiology.
The findings offer clinicians yet another tool for assessing these masses, which are one of the most common reasons for musculoskeletal imaging, wrote a team led by Dr. Aniket Tavare of Chapel Allerton Hospital in Leeds, U.K. When referring physicians identify a mass, they want to know if it's malignant.
"Shear-wave elastography has been used to aid lesion detection characterization in a variety of body sites, most commonly in the breast and liver, but also in the prostate and thyroid," the group wrote. "Within the field of musculoskeletal imaging, SWE has mainly been used in evaluation of tendon disorders but has not yet found widespread clinical use. ... We hypothesized that malignant soft-tissue masses have altered elasticity that is significantly different from that of benign masses, which can be detected using SWE."
The study included 206 adults (89 men and 117 women) who were referred for biopsy of a soft-tissue mass between December 2015 and March 2017. Each patient underwent ultrasound, MRI, and shear-wave elastography before biopsy; three musculoskeletal radiologists reviewed the ultrasound images alone and then the ultrasound and MR images together, classifying the lesions as benign, probably benign, probably malignant, or malignant.
Tavare's group calculated the area under the receiver operating characteristic curve (AUC) for shear-wave elastography transverse velocity (SWV) to determine its performance compared with that of ultrasound alone or ultrasound plus MRI.
Histological data showed that 38% of the 206 study participants had malignant lesions. The SWV measure showed good diagnostic accuracy for lesions classified as benign or probably benign on ultrasound alone, with an AUC of 0.87, the group wrote. However, the measure did not provide significant diagnostic information for lesions classified as probably malignant or malignant, whether or not that classification was made with the addition of MRI to ultrasound.
The study results show that while SWV alone was not diagnostic of malignancy in soft-tissue lesions, it improved the diagnostic performance of ultrasound in lesions initially categorized as benign or probably benign, according to Tavare and colleagues.
"Shear-wave elastography can be used to add confidence to diagnosis of soft-tissue masses that appear benign or probably benign using conventional B-mode ultrasound," the investigators concluded.