Automated, IHC/FISH-free, H&E histopathology image-based HER2 amplification, tumor infiltrating lymphocyte (TIL) and tumor heterogeneity profiling in breast cancer.

Abstract

593 Background: Digital pathology has fostered the development of automated diagnostic solutions. However, current technologies in breast cancer remain unable to determine HER2 amplification status, which is established by immunohistochemistry (IHC) and/or fluorescent in situ hybridization (FISH). These ancillary tests carry a significant cost, prolong diagnostic time and fail to capture HER2 tumor heterogeneity and tumor infiltrating lymphocyte (TIL) burden, both of which determine the effectiveness anti-HER2 targeted therapy. Methods: This study describes the real-life clinical context development and validation of a patented novel, universal, automated, white-box, scanning platform agnostic solution that determines HER2 amplification status, prognostically significant TIL levels and tumor heterogeneity index (HI) from hematoxylin and eosin (H&E) stained malignant breast biopsy whole slide images (WSIs) alone. Unlike conventional artificial intelligence-based approaches, the underlying proprietary algorithm’s prediction criteria are explainable and are based on deterministic, hard-coded observational relationships of scale constructed from image morphological features mapped to observables representing underlying tumor-related perturbations in biological pathways/mitotic checkpoints.This includes G1/S deregulation signatures reflecting oncogenic HER2-neu. Results: Blinded validation of HER2 status prediction (n = 197 WSIs; 118 independent cases/patients) showed excellent diagnostic performance (κ = 0.85) relative to existing standard-of-care methodologies. This was independent of WSI file format, background histology, tumor subtype/grade or hormone receptor status. The device also displayed good accuracy (92%) in determining TIL profiles, and its combined HER2-TIL and HER2-HI prediction scales both exhibited a significant association with progression-free survival (CoxPH hazard ratio: 1.856; 95% CI: 1.002-3.438; p = 0.049 and CoxPH hazard ratio: 3.45; 95% CI: 0.95-12.55; p = 0.060). Conclusions: This technology opens up the future possibility of bypassing existing ancillary HER2 profiling investigations, thus potentially reducing laboratory workloads/healthcare costs while accelerating diagnostic turnaround times for patient benefit. In the interim, if used as an adjunct tool, this device could provide an objective HER2 testing reference scale while the robustness of its prediction of patient response to anti-HER2 targeted therapy is fully explored.