Value Added of Preoperative Contrast-Enhanced Digital Mammography in Patients With Invasive Lobular Carcinoma of the Breast

To study the ability of contrast-enhanced digital mammography (CEDM) to accurately assess disease extent with CEDM compared to full-field digital mammography (FFDM) in patients with biopsy-proven invasive lobular carcinoma. We (ILC), we performed a single-institution retrospective review of patients with pre-operativepreoperative FFDM, CEDM, and gold reference-standard post-operativepostoperative histopathology. Both Lin's and Pearson's correlation coefficients measures were higher for CEDM (P < .05). CEDM outperformsoutperformed FFDM in assessing the extent of ILC, thereby improving surgical outcomes. Background: Invasive lobular carcinoma (ILC) is the second most frequently diagnosed breast cancer, accounting for 5% to 15% of all invasive breast cancers, yet it remains radiologically elusive in many cases. The goal of this study was to compare the ability to accurately assess disease extent with contrast-enhanced digital mammography (CEDM) and full-field digital mammography (FFDM) in patients with biopsy-proven ILC. Patients and Methods: A single-institution retrospective review of patients diagnosed with ILC with preoperative CEDM was performed. One of 3 blinded radiologist readers rereviewed cases within 1 month of another. Final size diameter was based on the largest dimension on recombined CEDM or FFDM and compared to the reference standard histopathology. Bland-Altman plots were used to visualize the differences between tumor size on imaging and pathology. Results: Thirty women were included. Mean tumor diameter was 27.0 mm (range, 7.0-118 mm) on postoperative histology, 26.0 mm on CEDM, and 16.4 mm on standard mammogram. For CEDM versus FFDM, 5 (16.7%) of 30 versus 9 (30.0%) of 30 cases underestimated pathology by > 10 mm and 5 (16.7%) of 30 versus 3 (10.0%) of 30 overestimated histopathology by > 10 mm, respectively. Two (6.7%) of 30 cases required surgical reexcision. Both Lin (0.87 vs. 0.55) and Pearson (0.87 vs. 0.70) correlation coefficient measures were higher for CEDM versus FFDM. Conclusion: CEDM outperforms standard digital mammography in ability to accurately assess disease extent in patients with biopsy-proven ILC, resulting in improved surgical outcomes. Future studies should compare surgical outcomes in patients with preoperative magnetic resonance imaging and CEDM in patients with ILC.