COMPARISON OF THE DIAGNOSTIC PERFORMANCE OF HIGH-FREQUENCY ULTRASOUNDAS A FIRST- OR 2ND-LINE DIAGNOSTIC-TOOL IN NON-PALPABLE LESIONS OF THE BREAST

To compare the diagnostic performance of high-frequency ultrasound (HF U) as a first- or second-line diagnostic tool in non-palpable lesions (NPL) of the breast and to define the place of HFU in the diagnostic p rocess, 89 women with this kind of lesion, previously detected by mamm ography, underwent HFU with 7.5-13 MHz transducers. The examinations w ere performed by two equally experienced operators of which only one ( operator I) was aware of the mammographic findings. The mammographic e xaminations revealed the following non-palpable lesions: asymmetry-hyp erdensity (17 cases), nodule (44 cases), stellate lesion (5 cases), mi crocalcifications (23 cases). Total sensitivity of HFU in the examinat ions, performed by operator I was 83%, while in the examinations perfo rmed by operator II (unaware of the mammographic findings) it was only 35%. In all cases HFU allowed the operators to determine the basic fe atures of the lesions. Our experience confirms that ultrasonography, e ven if performed with high frequency, cannot be proposed as a screenin g examination but may profitably be employed as a second-step techniqu e to characterize NPL previously identified by mammography. This 'seco nd-step' role can do the following: rule out true pathology (cases of false-positive mammography findings); furnish some basic features in t he case of local lesions; show other findings in the case of microcalc ifications, such as microcysts, 'filled duct' appearance, parenchymal inhomogeneities and nodules; guide interventional procedures; and loca lize lesions preoperatively.