Ultrasound Evaluation of Palpable Breast Masses in Correlation with FNAC /Histopathology

Abstract

Background: According to many studies the positive predictive value for biopsy can be increased by proper complete diagnostic work up in which sonography is also included. Improvements in imaging technique with high resolution ultrasonography, many studies have described the reliable signs to differentiate benign and malignant masses. However, there are very limited Indian studies to investigate the general applicability of US features to distinguish benign from malignant solid masses. Hence this study was carried out for, Ultrasonological characterization of palpable solid breast masses and categorizing each mass as benign and malignant and to correlate categorized benign and malignant breast masses with tissue diagnosis. Methodology: Our study was a prospective analysis. Our study included 50 patients of age range between 2275 years (mean age, 42 years) with history of palpable breast masses. Data for the study was collected from the patients referred to Department of Radio diagnosis at teaching hospitals attached to Bangalore Medical College and research institute, Bangalore for the period of two years. A structured, pre-prepared case proforma (CP) was used to enter the clinical history, physical examination findings, investigations-sonography and histopathology findings. Initially sonography was performed with BIOMEDICA ESOATE AUX scanner with 7.5-10 MHz linear array transducer and data was Obtained of only solid masses. Then tissue diagnosis was obtained in all 50 cases. Later the tissue diagnosis results were correlated with sonological findings by statistical analysis. Results: The US features most predictive of a benign tissue diagnosis were oval or round shape, circumscribed margins, and width-toAP dimension ratio greater than 1.4. The features most predictive of a malignant tissue diagnosis were spiculated or micro lobulated margins, irregular shape, ill-defined margins, and width-toAP dimension ratio of 1.4 or less. Some features were not reliable in differentiating between benign and malignant lesions. For example, the effects of masses on posterior echo intensity were not a useful determinant. Some features that showed excellent correlation with a benign or malignant tissue diagnosis were too infrequent to be generally applicable. For example, a hyperechoic lesion was very reliable as a predictor of benignity but was reported in only 2/ of the masses. Conclusion: In our study we performed the prospective analysis of the sono mammography findings in correlation with tissue diagnosis. The results of our study well correlated the results of the prior studies. The US features in our study most predictive of a benign tissue diagnosis were oval or round shape, circumscribed margins, presence of edge refraction, and width-to-AP dimension ratio greater than 1:4. Some features were not reliable in differentiating between benign and malignant lesions. For example, the effects of masses on posterior echo intensity were not a useful determinant. Some features that showed excellent correlation with a benign or malignant tissue diagnosis were too infrequent to be generally applicable. The evaluation of the cases was prospective, but the sample size was relatively small and we did not asses interobserver variability in the evaluation of these features and in the final assessments. However, the results of our study were encouraging in that we were able to identify the most applicable US features for differentiating benign from malignant solid masses. These features have the potential to help decrease the number of biopsies performed for benign solid masses.