4a Lesions Research Articles

Nachweis von Mikrokalk durch hochauflösende B-Mode-Sonographie bei BI-RADS-4a-Patientinnen

Ziel: Evaluation der diagnostischen Wertigkeit der hochauflösenden B-Mode-Sonographie zum Nachweis von Mikrokalk und mikrokalkassoziierten Herdbefunden bei Patientinnen mit BI-RADS-4a-Läsionen. Patientinnen und Methode: Bei 40 Patientinnen wurden eine Röntgenmammographie und eine B-Mode-Sonographie mit 13 MHz durchgeführt. Untersucht wurden: mit Röntgenmammographie: Ausdehnung der Mikrokalkareale und Darstellbarkeit assoziierter Herdbefunde; mit Ultraschall: Sensitivität des Mikrokalknachweises, Qualität der Darstellung, Ausdehnung der Mikrokalkareale, Darstellbarkeit assoziierter Herdbefunde und Durchführbarkeit einer ultraschallgestützten Biopsie. Ergebnisse: In der Röntgenmammographie betrug die mittlere Ausdehnung von Mikrokalkarealen 28 ± 21 mm. Sensitivität, Spezifität, positiver (PPV) und negativer prädiktiver Wert (NPV) und die Nachweisgenauigkeit mikrokalkassoziierter Herdbefunde betrugen 61,5, 57,9, 50, 45,8 und 47,5%. Die B-Mode-Sonographie erreichte eine Sensitivität von 100%. Die mittlere Ausdehnung der Mikrokalkareale betrug sonographisch 7 ± 3 mm und war damit signifikant geringer (p < 0,01). Es ergaben sich für Sensitivität, Spezifität, PPV, NPV und die Nachweisgenauigkeit 14,3, 84,2, 50, 47,1 und 47,5%. Die Durchführung einer ultraschallgestützten Biopsie erschien bei 22 (55%) Patientinnen möglich. Schlussfolgerung: Die Hochfrequenz-B-Mode-Sonographie ermöglicht einen hoch sensitiven Nachweis von Mikrokalk bei BI-RADS-4a-Läsionen und lässt eine ultraschallgestützte Biopsie bei etwa der Hälfte der Patientinnen durchführbar erscheinen.

Using Real-time Tissue Elastography for Breast Lesion Evaluation

The purpose of this study was to prospectively assess the performance of real-time tissue elastography (RTE) in the evaluation of breast masses and correlate RTE and American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) assessments with pathologic findings. Informed consent was obtained from all patients for this Health Insurance Portability and Accountability Act-compliant, Institutional Review Board-approved study. Patients with sonographically visible breast lesions for which a biopsy was recommended were considered potential study participants. Between October 2006 and February 2008, 186 consecutive women with 200 lesions were enrolled. Twelve lesions in 11 patients were excluded, resulting in a study population of 188 lesions in 175 women. After routine B-mode sonographic examination, RTE was performed using a manual free-hand compression technique. Study lesions were assigned elasticity scores (ES) based on the system proposed by Itoh et al (Radiology 2006; 239:341-350), where 1 is normal and 5 represents abnormal strain. The lesion size on RTE and B-mode imaging was compared. Results were correlated with BI-RADS assessment and pathologic findings. Pathologic examination revealed 61 of 188 malignancies (32.4%) and 127 of 188 benign lesions (67.6%). Of the malignant lesions, 84% had ES of 5 and 4, whereas 76% of benign lesions had ES of 1 and 2. The sensitivity of RTE was 92.7%, and specificity was 85.8%, with 4 false-negative and 16 false-positive results. Of the biopsy-proven benign BI-RADS 4A lesions, 63 of 76 (82.9%) had ES of 1 and 2, consistent with normal tissue. Real-time tissue elastography may provide additional characterization of breast lesions, improving specificity, particularly for low-suspicion lesions.

0491: Elastography for the Characterization of Nonpalpable Breast Lesions

We performed several prospective clinical studies to evaluate the role of sonoelastography for the characterization of nonpalpable breast lesions. First, 842 consecutive women who were scheduled to undergo US-guided core biopsy due to 864 breast lesions(79 cancers and 785 benign lesions) detected by supplemental screening US were examined with a commercialized sonoelastography. For the BI-RADS category 4a lesions, 28.5% (216 of 757) had a normal strain and 99.1% (214 of 216) of lesions with normal strain found out to be benign. Second, 300 women with 339 nonpalpable lesions were prospectively examined with sonoelastograpy and color Doppler US (CDUS) prior to biopsy. Of the 301 lesions with BI-RADS category 4a, 76 (25%) lesions showed normal strain on elastography and no vascularity on CDUS and all of them were found to be benign. Breast lesions diagnosed with DCIS by US-guided core biopsy with invasive components at surgery show less strain than pure DCIS at elastography regardless of the lesion size and B-mode US findings. Third, we evaluated the accuracy of neural network analysis of elastographic features at sonoelastography for the classification of 113 benign and 68 malignant breast tumors. Az values of the three elastographic features- mean (0.87), median (0.86) and mode (0.83)-were significantly higher than the Az values for the six B-mode features (0.54-0.69). In conclusion, addition of elastography to breast US has potential to reduce benign biopsy for BIRADS category 3 or 4a lesions that are detected by supplemental screening US.

Nonpalpable Breast Masses: Evaluation by US Elastography

ObjectiveTo compare the diagnostic performances of conventional ultrasound (US) and US elastography for the differentiation of nonpalpable breast masses, and to evaluate whether elastography is helpful at reducing the number of benign biopsies, using histological analysis as a reference standard.Materials and MethodsConventional US and real-time elastographic images were obtained for 100 women who had been scheduled for a US-guided core biopsy of 100 nonpalpable breast masses (83 benign, 17 malignant). Two experienced radiologists unaware of the biopsy and clinical findings analyzed conventional US and elastographic images by consensus, and classified lesions based on degree of suspicion regarding the probability of malignancy. Results were evaluated by receiver operating characteristic curve analysis. In addition, the authors investigated whether a subset of lesions was categorized as suspicious by conventional US, but as benign by elastography.ResultsAreas under the ROC curves (Az values) were 0.901 for conventional US and 0.916 for elastography (p = 0.808). For BI-RADS category 4a lesions, 44% (22 of 50) had an elasticity score of 1 and all were found to be benign.ConclusionElastography was found to have a diagnostic performance comparable to that of conventional US for the differentiation of nonpalpable breast masses. The authors conclude that BI-RADS category 4a lesions with an elasticity score of 1 probably do not require biopsy.