Automated Prediction of Breast Cancer Response to Neoadjuvant Chemotherapy from DWI Data
Shir Nitzan, Maya Gilad, Moti Freiman
TL;DR
This study tackles automated prediction of pathological complete response (pCR) to neoadjuvant chemotherapy in breast cancer using diffusion-weighted MRI (DWI). It introduces Size-Adaptive Lesion Weighting within nnU-Net to achieve fully automatic tumor segmentation, which feeds a PD-DWI pCR predictor to estimate treatment response. At pre-NAC, the method achieves a pCR prediction performance close to expert levels (AUC around $0.76$ versus a human benchmark of $0.796$), and during NAC it outperforms standard automated approaches (AUC around $0.729$ compared with $0.654$ and $0.576$). By removing the need for manual segmentation while maintaining robustness to NAC-induced histopath changes, the approach has strong potential to improve clinical planning for NAC in breast cancer.
Abstract
Effective surgical planning for breast cancer hinges on accurately predicting pathological complete response (pCR) to neoadjuvant chemotherapy (NAC). Diffusion-weighted MRI (DWI) and machine learning offer a non-invasive approach for early pCR assessment. However, most machine-learning models require manual tumor segmentation, a cumbersome and error-prone task. We propose a deep learning model employing "Size-Adaptive Lesion Weighting" for automatic DWI tumor segmentation to enhance pCR prediction accuracy. Despite histopathological changes during NAC complicating DWI image segmentation, our model demonstrates robust performance. Utilizing the BMMR2 challenge dataset, it matches human experts in pCR prediction pre-NAC with an area under the curve (AUC) of 0.76 vs. 0.796, and surpasses standard automated methods mid-NAC, with an AUC of 0.729 vs. 0.654 and 0.576. Our approach represents a significant advancement in automating breast cancer treatment planning, enabling more reliable pCR predictions without manual segmentation.
