Idiopathic Granulomatous Mastitis or Breast Cancer? A Comparative MRI Study in Patients Presenting with Non-Mass Enhancement.

OBJECTIVE: To compare and determine discriminative magnetic resonance imaging (MRI) findings of idiopathic granulomatous mastitis (IGM) and breast cancer (BC) that present as non-mass enhancement. MATERIALS AND METHODS: This retrospective study includes 68 IGM and 75 BC cases that presented with non-mass enhancement on breast MRI. All patients with a previous history of breast surgery, radiotherapy, or chemotherapy due to BC or a previous history of mastitis were excluded. On MRI images, presence of architectural distortion skin thickening, edema, hyperintense ducts containing protein, dilated fat-containing ducts and axillary adenopathies were noted. Cysts with enhancing walls, lesion size, lesion location, fistulas, distribution, internal enhancement pattern and kinetic features of non-mass enhancement were recorded. Apparent diffusion coefficient (ADC) values were calculated. Pearson chi-square test, Fisher's exact test, independent t test and Mann-Whitney U test were used as needed for statistical analysis and comparison. Multivariate logistic regression model was used to determine the independent predictors. RESULTS: IGM patients were significantly younger than BC patients (p < 0.001). Cysts with thin (p < 0.05) or thick walls (p = 0.001), multiple cystic lesions, (p < 0.001), cystic lesions draining to the skin (p < 0.001), and skin fistulas (p < 0.05) were detected more often in IGM. Central (p < 0.05) and periareolar (p < 0.001) location and focal skin thickening (p < 0.05) were significantly more common in IGM. Architectural distortion (p = 0.001) and diffuse skin thickening (p < 0.05) were associated with BC. Multiple regional distribution was more common in IGM, whereas diffuse distribution and clumped enhancement were more common in BC (p < 0.05). In kinetic analysis, persistent enhancement was more common in IGM, whereas plateau and wash-out types were more common in BC (p < 0.001). Independent predictors for BC were age, diffuse skin thickening and kinetic curve types. There was no significant difference in the diffusion characteristics. Based on these findings, MRI had a sensitivity, specificity and accuracy of 88%, 67.65%, and 78.32%, respectively, in differentiating IGM from BC. CONCLUSIONS: In conclusion, for non-mass enhancement, MRI can rule out malignancy with a considerably high sensitivity; however, specificity is still low, as many IGM patients have overlapping findings. Final diagnosis should be complemented with histopathology whenever necessary.

Comparison of mammography and ultrasound findings in the follow-up of patients with breast cancer treated with segmental mastectomy followed by intraoperative electron radiotherapy versus external whole breast radiotherapy

PURPOSE: This study aims to describe imaging findings in patients treated with intraoperative electron radiotherapy and compare them with those detected in patients treated with external whole breast radiotherapy (WBRT). METHODS: The study population consisted of 25 patients who received intraoperative radiotherapy [IORT (21 Gy)] as single-dose radiotherapy and a control group of 25 patients who received WBRT at the same institution. Mammography and ultrasound (US) findings were divided into three groups: minor, intermediate, and advanced. On mammography, mass lesions were considered advanced, and asymmetries or architectural distortions were considered intermediate. Oil cysts, linear scars, and the increase in parenchymal density were considered minor findings. On US, irregular non-mass lesions were considered advanced, and circumscribed hypoechoic lesions or planar irregular scars with shadowing were considered intermediate. Oil cysts, fluid collections, or linear scars were considered minor findings. RESULTS: On mammography, skin thickening (P = 0.001), edema (P < 0.001), increased parenchymal density (P < 0.001), dystrophic calcifications (P = 0.045), and scar/distortion (P = 0.005) were significantly more common in the WBRT group. On US, irregular non-mass lesions, which made interpretation considerably difficult, were significantly more common in the IORT group (P = 0.004). Dominant US findings were fluid collections and postoperative linear or planar scars in the WBRT group. Minor findings were more common in low-density breasts, and major findings (intermediate and advanced) were more common in high-density breasts on both mammographies (P = 0.011) and US (P = 0.027) in the IORT group. CONCLUSION: Ill-defined non-mass lesions detected on US in the IORT group have not been defined previously. Radiologists should be aware of these lesions because they can be confusing, especially in early follow-up studies. This study has found that minor findings are seen more frequently in low-density breasts, while major findings are more common in high-density breasts in the IORT group. This has not been reported before, and further studies with more cases are needed to verify these results.

The Role of Superb Microvascular Imaging and Shearwave Elastography in the Evaluation of Intraductal Papilloma-Like Lesions.

OBJECTIVES: The aim of this study was to investigate the role of quantitative values obtained by superb microvascular imaging (SMI) and shearwave elastography (SWE) in the prediction of malignancy in intraductal papilloma-like lesions (IDPL). METHODS: In the study, 61 patients between the ages of 14 to 73 years (mean age 44) diagnosed with IDPL on ultrasound (US) examination between the years 2020 and 2021 were included. The B-Mode US findings (shape, margins, size, echo pattern, and accompanying ductal dilatation), SMI vascular index (SMIvi), E-mean, and SWE-ratio values were recorded. RESULTS: There was a statistically significant difference between malignant (n = 14) and benign (n = 47) groups in terms of symptoms (P = .005), size (P = .042), shape (P = .002), margins (P = .001), echogenicity (P = .023), microcalcifications (P = .009), SMIvi (P = .031), E-mean (P < .005), and SWE-ratio (P = .007). According to receiver operating characteristic (ROC) curve analysis, sensitivity, specificity, accuracy, area under the curve (AUC), positive predictive values (PPV), and negative predictive values (NPV) were 57.1%, 87.2%, 80%, 0.722, 57.1%, 87.2% for US; 71.4%, 49%, 55.7%, 0.692, 30.3%, 85.7% for SMIvi; 85.7%, 71%, 74%, 0.864, 46%, 94.3% for E-mean, and 50%, 75.4%, 83%, 0.707, 91.5%, and 50% for SWE-ratio, respectively. Best results were obtained when SMI and SWE values were used together, achieving a sensitivity, specificity, accuracy, AUC, PPD, NPD of 78.6%, 93.6%, 93.4%, 0.872, 91.7%, and 93.9%, respectively. CONCLUSIONS: The SMI and SWE examinations are successful in the differentiation of benign and malignant intraductal lesions. They complement each other and contribute to B-mode US in managing IDPLs especially when used together. Our study is the first to compare the quantitative data of SWE and SMI in the differentiation of IDPLs.

Comparison of automated versus hand-held breast US in supplemental screening in asymptomatic women with dense breasts: is there a difference regarding woman preference, lesion detection and lesion characterization?

PURPOSE: To compare automated breast volumetric scanning (ABVS) with hand-held bilateral whole breast ultrasound (HHUS) prospectively in regards to patient workflow, woman preference, efficacy in lesion detection, and characterization. MATERIALS AND METHODS: Supplemental screening was performed with both ABVS and HHUS to 345 women with dense breasts and negative mammograms. Acquisition and evaluation times were recorded. Lesions were classified according to BIRADS US criteria and compared one to one. Women were recalled for a secondary HHUS examination if ABVS showed any additional lesions. Findings were compared based on biopsy results and/or 36-48 months of follow-up. RESULTS: Findings could be compared for 340 women. There were two carcinomas which were detected by both methods, with no interval cancers in the follow-up period. Recall rate was 46/340 (13.05%) for ABVS and 4/340 (1.18%) for HHUS. ABVS recalls decreased with experience. HHUS had more true negative (BIRADS 1-2) results, while ABVS had more false positive ones (p < 0.001). Positive predictive value was 4.17% for ABVS and 50% for HHUS. ABVS overdiagnosed shadowings (p < 0.01), distortions (p < 0.034), and irregular nodules (p < 0.001) in comparison to HHUS. At ABVS, 10.6% of women experienced severe pain. 59.7% stated that they would choose HHUS if they had the chance. CONCLUSION: ABVS is as good as HHUS in lesion detection. However, the recall rate is higher and positive predictive value is lower with ABVS, which could result in more follow-ups, and more anxiety for the women. More than 50% women stated they would prefer HHUS if they were given the chance.