Limitations of Conventional Contrast-enhanced MRI in Selecting Sentinel Node Biopsy Candidates among DCIS Patients

Abstract

Purpose: A better predictive model for occult invasive disease in ductal carcinoma in situ (DCIS) patients is essential to guide the tailored use of sentinel node biopsies. We hypothesized that recent improvement of contrast-enhanced breast magnetic resonance imaging (MRI) could provide more accurate information on the presence of occult invasion in DCIS patients. Methods: From a prospectively maintained database, we identified 143 DCIS patients diagnosed with needle biopsies in whom MRI images were available. Results: Sixty-five patients (45.5%) were upstaged to invasive carcinoma after curative surgery. Ultrasonographic lesion size, mass-appearance on mammography, type of needle used, and the presence of suspicious microinvasive foci were associated with increased likelihood of upstaging. Among the features of MRI, only mass-appearance was significantly associated with the presence of invasive disease (p=0.002). However, up to 50% of masses in MRI cases had mass-appearance on mammography as well. Other morphologic and pharmacokinetic features of MRI, such as shape, margin, and patterns of enhancement and washout, did not have a significant association. Conclusion: Among various morphologic and pharmacokinetic parameters of contrast-enhanced MRI, only mass-appearance was associated with occult invasive disease. Our results show the limitations of current contrast-enhanced MRI in predicting invasive disease in patients with preoperative diagnoses of DCIS.