Detection of invasive components in cases of breast ductal carcinoma in situ on biopsy by using apparent diffusion coefficient MR parameters

To evaluate whether apparent diffusion coefficient (ADC) parameters could identify invasive components in cases with ductal carcinoma in situ (DCIS) diagnosed by biopsy. This retrospective study was approved by the institutional review board and the requirement to obtain informed consent was waived. Sixty-nine consecutive women with 70 lesions diagnosed with DCIS by biopsy underwent breast magnetic resonance (MR) imaging. Multiple regions of interest were placed (as many as possible) within the lesion on ADC maps. The minimum ADC values and the ADC difference values obtained as the difference between minimum and maximum ADCs were evaluated. Surgical specimens revealed 51 lesions with pure DCIS and the remaining 19 lesions with DCIS with invasive components (DCIS-IC). The minimum ADC value for DCIS-IC (0.99 +/- 0.04 x 10(-3) mm(2)/s) was significantly lower than that of pure DCIS (1.15 +/- 0.03 x 10(-3) mm(2)/s) (PaEuro...aEuro parts per thousand= aEuro...0.0037). The ADC difference value for DCIS-IC (0.38 +/- 0.05 x 10(-3) mm(2)/s) was significantly higher than that of pure DCIS (0.17 +/- 0.03 x 10(-3) mm(2)/s). ROC curve analysis for differentiating DCIS-IC from pure DCIS revealed that the area under the curve was 0.71 for minimum ADC value and 0.77 for ADC difference value. The minimum ADC values and ADC difference values could suggest the presence of invasive components. aEuro cent Identification of invasive components in DCIS before treatment is clinically important. aEuro cent Diffusion-weighted MR imaging can help lesion assessment in breast cancer. aEuro cent The minimum ADC value may suggest the presence of an invasive component in DCIS. aEuro cent The ADC difference value also suggests the presence of an invasive component in DCIS. aEuro cent Preoperative evaluation of diffusion-weighted MR imaging may help surgical planning for DCIS.