High Prevalence of MRI-Detected Contralateral and Ipsilateral Malignant Findings in Patients With Invasive Ductolobular Breast Cancer: Impact on Surgical Management

Abstract

INTRODUCTION: Invasive breast cancer comprises a spectrum of histologic changes with purely lobular and purely ductal cancer on either side and mixed lesions in between. Our aim was to evaluate to what extent preoperative magnetic resonance imaging (MRI) leads to the finding of additional malignancies and the effect on surgical management in the subcategory of women with invasive ductolobular disease. PATIENTS AND METHODS: From 2007 to 2012, 109 patients diagnosed with breast cancer containing a lobular component underwent preoperative MRI. The MRI findings were compared with the findings from mammography and ultrasonography. Clinically relevant additional MRI findings were verified histologically. The histologic slides were reviewed, and the percentage of the lobular component was determined. In a multidisciplinary setting, the TNM classification and surgical policy were determined using the conventional imaging findings and as a scenario that included preoperative MRI. RESULTS: MRI revealed additional malignant foci in 28 of 109 patients (26%). More extensive disease was seen in 25 patients (23%). The preoperative MRI findings changed the TNM classification in 42% of the patients and altered the surgical policy in 37%. No correlation was found between the lobular component and the probability of detecting additional malignant foci, more extensive disease, or the frequency of a change in TNM classification or surgical policy. According to the final pathology report, the change in surgical policy was justified in 85% of the patients. CONCLUSION: In patients with breast cancer presenting with lobular differentiation at biopsy, preoperative MRI can lead to the detection of additional malignancies and clinically relevant changes in surgical policy in a high percentage of patients, irrespective of the lobular component. The use of MRI as a part of the standard workup of such patients deserves consideration.