en Radiology Radiology Original Article Original Article <span style="font-family:Times New Roman;"><span style="font-size:14px;"><span style="color:#0033ff;"><strong><em>Background</em></strong><em>:</em></span> We aimed to compare the diagnostic accuracy of mammography and ultrasonography and their breast imaging-reporting and data system (BI-RADS) classification versus breast core needle biopsy (CNB) findings in distinguishing the breast masses.<br> <span style="color:#0033ff;"><strong><em>Methods</em></strong><em>:</em> </span>This cross-sectional study was conducted during 2016-2018 on female patients who were referred to a radiology center in Babol, northern Iran, for routine screening and/or for CNB. Patients underwent sonography and mammography by a senior radiologist. The breast lesions were also evaluated according to BI-RADS classification. CNB was performed on the breast masses by the same radiologist and pathological procedures were performed by an expert pathologist. Descriptive statistics were used to analyze the data.<br> <span style="color:#0033ff;"><strong><em>Results</em></strong><em>:</em></span> In total, 213 breast masses were finally assessed, of which 107 (50.2 %) masses were benign and 106 (49.8 %) masses were malignant. The sensitivity for mammography and ultrasound alone was 72.6% and 68.9%, respectively. This rate for combined mammography and ultrasound was 84.9%. About BI-RADS classification, 28 masses were classified as BI-RADS 3, 99 as BI-RADS 4A, 4 as BI-RADS 4B, 18 as BI-RADS 4C, and 64 as BI-RADS 5. BI-RADS 4A had the highest sensitivity (70.1%) among BI-RADS categories. The highest specificity pertained to BI-RADS 3 and 5 (100%) among BI-RADS categories. Also, the highest accuracy was related to BI-RADS 5 (80.3%).<br> <span style="color:#0033ff;"><strong><em>Conclusion</em></strong><em>:</em></span> The results of the present study showed that combined mammography and ultrasound had a higher rate of accuracy than mammography or ultrasound alone. Furthermore, the imaging methods BI-RADS classification had an acceptable positive predictive value.</span></span> Ultrasonography, mammography, core needle biopsy, breast malignancy 573 579 http://caspjim.com/browse.php?a_code=A-10-2130-1&slc_lang=en&sid=1 Naser Ghaemian nghaemian@gmail.com 100319475328460032150 100319475328460032150 No Department of Radiology, Shahid Beheshti Hospital, Babol University of Medical Sciences, Babol, Iran Neda Haji Ghazi Tehrani nhgt87@yahoo.com 100319475328460032151 100319475328460032151 No Student Research Committee, Babol University of Medical Sciences, Babol, Iran Mehrdad Nabahati mehrdadnabahati@gmail.com 100319475328460032152 100319475328460032152 Yes Department of Radiology, Shahid Beheshti Hospital, Babol University of Medical Sciences, Babol, Iran