Utility of signal enhancement ratio on DCE-MRI for detection of residual breast cancer following surgery or neoadjuvant chemotherapy – a pilot study

Abstract

Accurate detection of residual disease following breast-conserving surgery or neoadjuvant chemotherapy is essential for appropriate treatment planning in breast cancer. This retrospective pilot study aimed to evaluate the utility of the signal enhancement ratio (SER), a quantitative parameter derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), in detecting residual malignancy. Fourteen women who underwent 3T bilateral breast DCE-MRI at a tertiary care centre in central India were included. SER maps were generated using voxel-wise calculations, and regions of interest were placed on areas of maximum enhancement. Residual disease was confirmed histologically in 4 patients and excluded in 10 patients (8 by histopathology, 2 by long-term follow-up). Median SER was significantly higher in residual disease (136.2) compared to non-residual cases (44.0, p < 0.05). Morphological features showed high sensitivity (100%) but low specificity (50%). An SER cut-off of 90 improved specificity to 90% without loss of sensitivity. SER mapping may enhance diagnostic accuracy in post-treatment breast MRI, supporting its use as a quantitative adjunct.