The aim of this study is to identify the imaging features associated with the upgrade to invasive cancer in patients diagnosed with low-grade Ductal Carcinoma in situ (DCIS) in core needle biopsy.
Between 2007 to 2017, 1193 patients were diagnosed DCIS on core needle biopsy in our institution. There were 287 cases of low-grade DCIS. We analyzed the final surgical pathology and the imaging findings of low-grade DCIS cases. Entry criteria included patients underwent all three modalities in the breast (mammography(MG), ultrasonography(US), and MRI). 20 cases didn't get further intervention. 19 patients didn't undergo breast Magnetic Resonance Imaging (MRI). The final population comprised 269 cases. In each case, dedicated breast imaging radiologist reviewed every modality with limited information (laterality of the lesion). We obtained BI-RADS descriptor of each lesion in MG, US, and MRI. We identified the characteristics of upgrade cases. We compared each imaging features between upgrade and non-upgrade cases using t-test. MedCalc was used as statistic tool.
Among 239 cases of low-grade DCIS, 49 cases were upgraded to invasive ductal carcinoma. Fourteen cases were upgraded to microinvasive duct carcinoma. There were three invasive lobular carcinomas, three mucinous carcinomas, three intraductal papillary carcinoma, five lobular carcinomas in situ, and one mixed ductal and lobular carcinoma in situ. 161 cases have remained DCIS at final pathology. More than half of IDC upgrade cases(29/49) were presented as hyperdense mass in mammography, whereas only 20.4% (33/161) of non-upgrade cases showed mass at mammography. (p < 0.05) In MRI, non-upgrade cases showed a small number(16/161) with wash out pattern in delayed phase. In contrast, Twenty seven cases (55%) of IDC upgrade series showed the early rapid rise and delayed wash out pattern.
Our institution's low- grade DCIS to IDC upgrade rate was 20.5%. The IDC upgrade population shows the mass on mammography and delayed washout pattern in dynamic studies on MRI. The non-upgrader tend to be presented as calcification on mammography and plateau delayed enhancement.
Clinical trial identification
Legal entity responsible for the study
A Jung Chu.
Has not received any funding.
All authors have declared no conflicts of interest.