Complementary imaging of solid breast lesions:contribution of ultrasonography, fine-needle aspiration biopsy, and high-field and low-field MR imaging

• Main Author: Reinikainen, H. (Heli)
• Format: Doctoral Thesis
• Language: English
• Published: University of Oulu 2003
• Subjects: Doppler; MR imaging; biopsy; breast neoplasms; contrast media; diagnosis; low-field; ultrasonography
• Online Access: http://urn.fi/urn:isbn:9514270525; http://nbn-resolving.de/urn:isbn:9514270525

Abstract This study aimed to assess the value of B-mode, nonenhanced and enhanced power Doppler ultrasonography (US), fine-needle aspiration biopsy (FNAB) and magnetic resonance (MR) imaging as adjunctive tools in breast diagnostics. The findings were compared to histology. The mammograms and US images of 84 palpable breast lesions were retrospectively reviewed, 63 of them also blindly. The cytologic reports of 57 lesions were reviewed. Eighty-one (96%) of all the 84 lesions, and 52 of the 53 cancers were visible as a local abnormality at US. The sensitivity, specificity, and overall accuracy of FNAB cytology was 92%, 83%, and 88%, respectively. There were no false negative malignancies in the three modalities combined. Sixty-five lesions not unequivocally benign at mammography were examined with B-mode, unenhanced and enhanced power Doppler US. Vascularity was also analyzed quantitatively. The sensitivity, specificity, and overall accuracy of the morphologic evaluation was 100%, 10%, and 57%, respectively. Rounded lesions were more vascular than spiculated lesions, but vascular assessment was only helpful when supporting a benign morphology. Forty breast lesions were examined with dynamic MR imaging and power Doppler US by obtaining time-signal intensity curves, which were analyzed morphologically and quantitatively. The shape of the MR curve acchieved 90% accuracy in differentiating between benign and malignant lesions. It enabled also differentiation between fibroadenomas and malignancies. The accuracy of the US curve was 38%. Quantitatively, statistically significant differences were found using all the MR variables, except between fibroadenomas and malignancies. Using the US variables, no significant difference was found. Twenty-eight patients (34 breasts) were examined by dynamic low-field and high-field MR imaging. The images were analyzed separately by two radiologists paying attention to lesion morphology and enhancement kinetics. In 27 breasts, results were compared to biopsy. Kappa statistics was used to compare the performance between the MR-scanners and readers. The sensitivity was 100% and 100%, the specificity 82% and 73%, and the accuracy 93% and 89% at low and high field, respectively. The inter-MR-scanner kappa value was 0.77 (substantial agreement), while the inter-observer kappa value was 0.86 and 0.81 at low and high field, respectively (almost perfect agreement).