Optimizing DCE-MRI Interpretation to Improve Tumor Extent Assessment and Margin Negativity in Breast-Conserving Surgery for Lobular Carcinoma

Motivation: Preoperative breast MRI has not reliably improved negative margin achievement in breast-conserving surgery for invasive lobular carcinoma. Goal(s): This study aims to determine the optimal DCE-MRI phase and assess the impact of including mass or non-mass enhancements for accurate tumor extent assessment in lobular carcinoma. Approach: We analyzed correlation coefficients between tumor sizes on histopathology and DCE-MRI, evaluating variations by lesion type (mass vs. non-mass), imaging phase (early vs. delayed), and cancer type (lobular vs. ductal). Results: Lobular carcinoma was generally underestimated on MRI, with the highest correlation observed when both lesion types were included, especially during the delayed phase at DCE-MRI. Impact: Incorporating both mass and non-mass enhancements in the delayed phase of DCE-MRI could improve preoperative assessment accuracy for lobular carcinoma, helping surgeons achieve negative resection margins and potentially reducing reoperation rates in breast-conserving surgery.