Automated breast ultrasound (ABUS) can be successfully used in the visualisation and characterisation of breast lesions, and can supplement mammography in the detection of non-calcified carcinomas in women with dense breasts. This is the conclusion of the study 'The performance of 3D ABUS versus hand-held ultrasound in the visualisation and BI-RADS characterisation of breast lesions in a large cohort of 1,886 women', originally published in European Radiology.
The study aimed to evaluate ABUS compared with HHUS in the visualisation and BI-RADS characterisation of breast lesions. The study involved 1,886 women with breast density category C or D - aged 48.6 ±10.8 years. All participants underwent ABUS and HHUS examination and a subcohort of 1,665 women also underwent a mammography exam.
"We reported a high overall agreement (99.8%) in BI-RADS assessment between ABUS and HHUS," says Athina Vourtsis, director and radiologist at Diagnostic Mammography in Greece. "More importantly, our results highlighted the value of ABUS and its integration in supplementing mammography by identifying non-calcified carcinomas that were obscured by dense breast tissue. Our results are in concordance with other studies that have found that multiplanar reconstruction data increases radiologists' diagnostic approach. The reported interpretation time was approximately three minutes per examination, allowing an efficient integration of ABUS into clinical workflow."
These results are consistent with a study recently conducted at the University Hospital Quirónsalud, Madrid, comparing the performance of ABUS and HHUS. In the study, which involved 155 patients following mammography, participants underwent an ABUS exam (performed by a technician trained and informed by a radiologist) and a HHUS exam performed by a different radiologist.
"Our study showed the same reliability between the ABUS and HHUS studies, however, ABUS provides the advantage that the radiologist is able to analyse the images without having to perform the ABUS exam personally," explains Dr Isaac Daimiel Naranjo of the Diagnostic Imaging Service at the university. "Additionally, ABUS provides the ability to store the result of the test in the patient's digital medical history, which allows comparison of ABUS results over time, since the exam is reproducible."
According to Professor László Tabár, a professor emeritus of radiology at Uppsala University, Sweden, "Breast ultrasound has been recognised as an invaluable tool in supplementing mammography in women with intermediate risk. However, known limitations of HHUS, including subjectivity and operator dependence, have restricted its applicability for populationbased screening. Shown to increase detection of 26-30% more invasive cancers when used in conjunction with mammography, ABUS is patient friendly, can be performed by a trained technologist or nurse, is reproducible and not subjective - it is specifically designed for screening large numbers of asymptomatic women with dense breasts."
"Several studies have reported the added value of the coronal plane on radiologist performance by demonstrating a retraction phenomenon sign; defined as merging of straight spicules that radiate perpendicularly in the periphery of the surface of a solid mass," Vourtsis adds. "This sign corresponds to an architectural distortion and has high sensitivity and specificity for malignancy.
Our study showed that an architectural distortion visualised on the coronal plane was the only sign of an invasive lobular carcinoma; while two radial scars were detected also on the coronal plane but not recognised in mammography or HHUS. Therefore, ABUS seemed to confer an added value on the coronal plane by displaying the architectural distortions."
According to Vourtsis, well-trained technologists, adequate compression of the breast, and meticulous application of coupling lotion are key to produce an efficient ABUS examination and to improve performance.
"The ability of ABUS to separate the image acquisition from interpretation and to provide standardised images would substantially accelerate the application of 3D ABUS in high-volume screenings, with the goal of earlier detection and better outcomes," Vourtsis concluded.