Diagnostic Performance of ADC for Non-mass-like Breast Lesions on MR Imaging

Abstract

We assessed the usefulness and limitations of utilizing apparent diŠusion coe‹cient (ADC) values on diŠusion-weighted imaging (DWI) for the diŠerential diagnosis of benign and malignant non-mass-like breast lesions. We retrospectively reviewed 27 such lesions (16 malignant, 11 benign) detected on magnetic resonance (MR) imaging and analyzed the enhancing patterns of dynamic contrast-enhanced DCE-MRI (distribution and internal enhancement), kinetic curve patterns, and ADC values. All images were obtained with a 1.5-tesla MR unit, with patients supine. On DCE-MRI, malignant lesions tended to show either segmental or branching-ductal distribution, and when lesions with these patterns were considered malignant, sensitivity was 68.8z; speciˆcity, 63.6z; positive predictive value (PPV), 73.3z; negative predictive value (NPV), 58.3z; and accuracy, 66.7z. Kinetic curve analysis did not reliably diŠerentiate benign and malignant non-mass-like lesions. There was no signiˆcant diŠerence between the mean ADC value of the malignant lesions, 0.968×10 -3 mm 2 /s at b＝1000 s/mm 2 , and that of benign lesions, 1.207×10 -3 mm 2 /s (P ＝0.109). Receiver operating characteristic (ROC) analysis revealed the most eŠective threshold of ADC value for diŠerentiating tumors as 1.1×10 -3 mm 2 /s; values lower than this were observed more often in malignant than benign lesions (P＝0.054). Us of this threshold yielded sensitivity of 68.8z; speciˆcity, 72.7z; PPV, 78.6z; NPV, 61.5z; and accuracy, 70.4z. Combining the ADC value criteria with the analysis of DCE-MRI pattern increased sensitivity to 93.8z, negative predictive value (NPV) to 85.7z, and accuracy to 77.8z but decreased speciˆcity to 54.5z. Use of ADC values does not adequately improve DCE-MRI performance for diŠerential diagnosis of non-mass-like breast lesions, but adding the ADC value criteria to the DCE-MRI pattern analysis improves sensitivity, NPV, and accuracy.

Simple magnetic resonance imaging criteria can differentiate ductal carcinomas in situ from invasive carcinomas

“…These lesions are commonly associated to NME pattern and frequently display less suspicious kinetic enhancement characteristics 17,18 , which is in agreement to our own results. When microinvasion or frank invasion ensues, the imaging findings tend to become more typically suspicious 19 .…”

Characterization of Suspicious Breast Lesions with Dynamic Contrast enhanced MRI In comparison to Conventional mammography and Ultrasonography

“…Ring enhancement was found in one malignant case. Homogenous enhancement was found in 15 lesions, 2 (13.3%) were benign and 13(86.7%) were malignant.In our study there was no statistical correlation between the pathologically proven benign and malignant lesions regarding their enhancement pattern except the non enhancing internal septations and this may be attributed to the small number of the studied patients, however our all pathologically proven benign cases did not show enhancing internal septations (100 % specificity).Imamura et al [27] found in his study that malignant non mass lesions tended to show either segmental or branching ductal distribution, and when lesions with these patterns are considered malignant the sensitivity & specificity were 68.8% and 63.6% respectively. He also reported that using the enhancement pattern in differentiation between benign and malignant lesions is often difficult with non mass like enhancement as there is no standarized method for interpreting them.…”

“…Imamura et al [27] found in his study that malignant non mass lesions tended to show either segmental or branching ductal distribution, and when lesions with these patterns are considered malignant the sensitivity & specificity were 68.8% and 63.6% respectively. He also reported that using the enhancement pattern in differentiation between benign and malignant lesions is often difficult with non mass like enhancement as there is no standarized method for interpreting them.…”

Nonmalignant Breast Lesions: ADCs of Benign and High-Risk Subtypes Assessed as False-Positive at Dynamic Enhanced MR Imaging

“…The below-threshold ADCs of most high-risk lesions are not surprising owing to their histologic similarity to malignant lesions. By far, the majority of nonmalignant lesions reported in prior DW imaging studies were fibroadenomas and fibrocystic changes (12,19,22,36,42,43). Fibroadenomas are generally presumed to have higher ADCs because of stromal myxoid change and consequent higher water mobility (24).…”