Impact of breast mass size on accuracy of ultrasound elastography vs. conventional B-mode ultrasound: a meta-analysis of individual participants.

ABSTRACT

OBJECTIVES: To conduct an individual patient data meta-analysis comparing the diagnostic performance of ultrasound elastography (USE) versus B-mode ultrasound (USB) across size ranges of breast masses. METHODS: An extensive literature search of PubMed and other medical/general purpose databases from inception through August 2011 was conducted. Corresponding authors of published studies that reported a direct comparison of the diagnostic performance of USE using the elasticity score versus USB for characterisation of focal breast masses were contacted for their original patient-level data set. Summary diagnostic performance measures were compared for each test within and across three mass size groups (<10 mm, 10-19 mm, and >19 mm). RESULTS: The patient-level data sets were received from five studies, providing information on 1,412 breast masses. For breast masses <10 mm (n = 543; 121 malignant), the sensitivity/specificity of USE and USB were 76 %/93 % and 95 %/68 %, respectively. For masses 10-19 mm of size (n = 528; 247 malignant), sensitivity/specificity of USE and USB were 82 %/90 % and 95 %/67 %, respectively. For masses >19 mm of size (n = 325; 162 malignant), sensitivity/specificity of USE and USB were 74 %/94 % and 97 %/55 %, respectively. CONCLUSION: Regardless of the mass size, USE has higher specificity and lower sensitivity compared to USB in characterising breast masses. The performance of each of these two tests does not vary significantly by mass size.