US screening has been performed using hand-held probes that are used to scan the entirety of both breasts. The technique however, requires practice and is generally performed by a physician. Recently, continuing technological advancement has made available whole-breast US scanning using an automated probe, which images wide field of view of breast tissue in three dimension (3D) reconstructed images.
From 2007.11-2007.12, 134 bilateral whole breast US was obtained using U-systems in 67 consecutive women who were scheduled to undergo US guided needle biopsy due to 72 suspicious breast masses (24 invasive cancers and 48 benign lesions). Detection rate of malignant nodule (91.7% to 95.8 %) was significantly higher than those of benign nodule (56.2% to 66.7 %) when the 3 radiologists read the 3D breast volume data. In another study, we assessed the performance of 3 radiologists for the detection of breast cancers using 3D ABUS (40 diseased and 37 normal). Almost 95 % of cancers were consistently detected with variable false positive rates (10-40%) by the radiologists. Most of false positive findings were associated with posterior shadowing beneath Cooper's ligament.
Our study suggests that the use of ABUS and interpretation with 3D volume data has the potential to reduce the recall rate for benign masses without missing the malignant masses. Even though substantial degree of cancer detection was achieved by using 3D breast volume data, radiologists' experience and training are still needed to identify small cancers and to reduce false positive rates. CAD systems may assist the radiologist in the early detection of breast cancer by highlighting suspicious areas seen on ABUS.