Comparison of 3D-Automated Breast Ultrasound With Handheld Breast Ultrasound Regarding Detection and BI-RADS Characterization of Lesions in Dense Breasts: A Study of 592 Cases.

RATIONALE AND OBJECTIVE: We aimed to compare the diagnostic performance of an automated breast ultrasound system (ABUS) with handheld ultrasound (HHUS) in the detection and characterization of lesions regarding BI-RADS classification in women with dense breasts. MATERIALS AND METHODS: After ethical approval, from July 2017 to August 2019, 592 consecutive patients were enrolled in this prospective study. On the same day, patients underwent ABUS followed by HHUS. Three breast radiologists participated in this study. The number and type of lesions and BI-RADS categorization of both ABUS and HHUS examinations of each patient were recorded in an excel file. The level of agreement between the two ultrasound systems in terms of lesion number and BI-RADS category were analyzed statistically. RESULTS: ABUS and HHUS detected 1005 and 1491 cystic and 270 and 336 mass lesions in 592 patients respectively. ABUS and HHUS detected 171 and 167 positive/suspicious cases (BIRADS 0/3/4/5). Forty suspicious lesions underwent core needle biopsy whereas 11 malignant lesions were detected by both methods. The remaining lesions were followed with a mean of 31 months. The mean size of solid lesions detected by HHUS and ABUS was 7.67 mm (range 2.1-41 mm) and 7.74 mm (range 2-42 mm) respectively. The agreement for detection of cystic lesions between two methods for each breast was good (kappa: 0.61-0.62 p < 0.001). The agreement of two methods for solid mass lesions for each breast was moderate (k = 0.57-0.60 p < 0.001). There was good agreement between the two methods for detecting suspicious lesions (kappa = 0.66 p < 0.001). CONCLUSION: The level of agreement of ABUS and HHUS for dichotomic assignment of BIRADS categories was good. Although ABUS detected fewer lesions compared to HHUS, both methods detected all malignant lesions. ABUS is a reliable method for the detection of malignancy in dense breasts.

Volume Navigation Technique for Ultrasound-Guided Biopsy of Breast Lesions Detected Only at MRI.

OBJECTIVE: The purpose of this study is to assess the utility of a volume navigation technique (VNT) for ultrasound-guided biopsy of MRI-detected, but sonographically ambiguous or occult, breast lesions. SUBJECTS AND METHODS: Within a recruitment period of 13 months (January 1, 2014, through February 1, 2015), 22 patients with 26 BI-RADS category 4 or 5 lesions that were detected at MRI but missed at second-look ultrasound were reimaged using a rapid sequence and a flexible body coil in a 3-T MRI scanner. Patients were supine, with three skin markers placed on the breasts. MRI volume data were coregistered to real-time ultrasound in a dedicated platform, and MRI-detected lesions (six masses, 11 nonmass enhancements, eight foci, and one architectural distortion) were sought using VNT-guided ultrasound. Five needle biopsy specimens were obtained either from each sonographically detected lesion (n = 11) or from VNT-guided sonographically localized breast volume corresponding to the MRI-detected, but still ultrasound-occult, lesions (n = 15). RESULTS: Histopathologic analysis revealed 18 benign and six malignant lesions. The remaining two lesions, both of which appeared as masses at MRI, were high risk and were upgraded to carcinoma after excisional biopsy. All malignant lesions underwent curative surgery; the final histopathologic diagnoses remained unchanged. Of the six malignant lesions, one was a mass, three were nonmass enhancements, and two were enhancing foci at MRI. Three malignant lesions were occult at ultrasound, and three were discerned as subtle hypoechoic changes. No benign lesion was sonographically visualized as a mass, and none progressed, with 56% disappearing at MRI performed during the follow-up period (mean, 14 months). CONCLUSION: Coregistration of MRI and real-time ultrasound enables sonographic localization of breast lesions detected at MRI only. VNT is a feasible alternative to MRI-guided biopsy of ultrasound-occult breast lesions.

Use of a Volume Navigation Technique for Combining Real-Time Ultrasound and Contrast-Enhanced MRI: Accuracy and Feasibility of a Novel Technique for Locating Breast Lesions.

OBJECTIVE: The objective of this study was to evaluate the accuracy of the volume navigation technique for combining real-time ultrasound and contrast-enhanced MRI (CE-MRI) of breast lesions. SUBJECTS AND METHODS: Thirty-eight women with single breast lesions underwent 3-T MRI. A 3.5-minute CE-MRI sequence was used, as was a flexible body coil. Patients underwent imaging in the supine position, with three markers placed on their breasts. Real-time sonographic images were coregistered to the preloaded breast CE-MRI volume by coupling skin markers, with the use of an electromagnetic transmitter positioned next to the subjects. The transmitter detected the spatial positions of the two electromagnetic sensors mounted on the transducer bracket. After this fusion process in 3D space was completed, divergences in the location of the center of each lesion on CE-MRI and ultrasound images were analyzed. RESULTS: The mean lesion size was 17.4 mm on ultrasound and 17.9 mm on MRI, whereas the mean (± SD) misalignment of the lesion centers on CE-MRI and ultrasound was 3.9 ± 2.5 mm on the x-axis (mediolateral view), 3.6 ± 2.7 mm on the y-axis (anteroposterior view), and 4.3 ± 2.6 mm on the z-axis (craniocaudal view). No lesion had a misalignment greater than 10 mm on any of three axes. The accuracy of volume navigation was independent of patient age and the lesion size, location, and histopathologic findings (p > 0.05). Intermediate lesions, which had a depth of center of 11-20 mm on ultrasound had a mean misalignment of 2.6 ± 1.9 mm, compared with 5.5 ± 2.2 mm for deep lesions, which had a depth of center greater than 20 mm (p = 0.049). CONCLUSION: The volume navigation technique is an accurate method for coregistration of CE-MRI and sonographic images, enabling lesion localization within a limited volume.

Outcomes of unconventional utilization of BI-RADS category 3 assessment at opportunistic screening.

Background An important difficulty regarding the Breast Imaging Reporting and Data System (BI-RADS) category 3 assessment is the need for extensive diagnostic workup and an additional 6-month follow-up study. Purpose To evaluate the feasibility of the BI-RADS category 3 assessments at opportunistic screening. Material and Methods Mammography charts of 9062 screening patients in a major teaching hospital situated in an urban setting of a developing country were evaluated retrospectively (1997-2010). BI-RADS category 3 patients, called for a 6-month follow-up, which comprised a single-view spot or magnification mammogram. The length of follow-up period, compliance to periodic mammographic surveillance, cancer detection rate, and negative predictive values of category 3 assessments were calculated. Results Of the screened population, 9.2% were assigned BI-RADS category 3, and 31.2% of these cases were lost to follow-up. The mean follow-up period for 606 patients was 36.9 months. The negative predictive values for 6-month, 12-month, and final control studies were 90.9%, 87.5%, and 100%, respectively. Patient compliance for 6 months, 12 months, and any control evaluations beyond 12 months was low (50.0%, 29.8%, and 47.5%, respectively). Cancer detection rate was 0.8%. Conclusion Results of the study supports the feasibility of the BI-RADS category 3 assessments at opportunistic screening without any additional diagnostic workup. The practice of category 3 assessment following screening mammograms may be a more cost-effective method for developing countries with high recall rates and low resources in eliminating the maximum risk with minimum cost within the limits of available resources.