Whole Slide Image Classification Using Deep Learning.

Loading...
Thumbnail Image

Embargo End Date

2026-02-20

ICR Authors

Authors

Fourkioti, O

Document Type

Thesis or Dissertation

Date

2025-02-20

Date Accepted

Abstract

The digital transformation of histopathological assessment through Whole Slide Imaging (WSI) has sparked a revolution in digital pathology, primarily propelled by advancements in artificial intelligence (AI) and deep learning (DL). This thesis seeks to the contribute to this ongoing technological evolution by developing, and evaluating methods that broaden the current capabilities of pathological diagnostics. Specifically, we focus on WSI classification tasks, using solely the visual information present in the histology images, without incorporating any other data modalities. However, WSI classification models struggle to generalise on new, unseen data due to the limited availability of diverse and standardized histopathology datasets. In the first part of our thesis, we introduce a new a diverse soft tissue sarcoma (STS) dataset. The STS dataset comprises 1163 WSIs from 303 patients collected from the Royal Marsden Hospital (RMH). This dataset, spanning over 12 subtypes, is intended to be publicly accessible, fostering further studies in the field of WSI analysis and contributing to the development of models with enhanced generalizability. A recent trend emerging in WSI classification is adopting graph-based approaches, where every tile within a WSI represents the central node of a graph and its spatially closest neighbouring tiles constitute the surrounding nodes. Many WSI approaches commonly use a fixed number of neighbours for constructing the graphs. In the second part of our thesis, we explore whether the contextual information provided by neighbouring tiles enhances or hinders the network's performance in identifying patterns and features relevant to the performance of the WSI classification models. Through systematic variations in the content and arrangement of neighbouring tiles, we explore this aspect using two histopathology datasets. In the third part of our thesis, we present Context-aware Multiple Instance Learning. (CAMIL) addresses the complex challenges of intra- and intertumoral heterogeneity by leveraging dependencies among tiles within WSIs. Our findings, validated on two widely used histopathology datasets, namely camelyon16 and TCGA- NLSC, demonstrate substantial enhancements in classification performance. In the fourth part our thesis, we introduce an instance-based loss inspired by semi-supervised anomaly detection (AD). Leveraging the available slide-level labels, the AD-loss plays a crucial role in discerning between normal and anomalous tiles in WSIs. When dealing with normal slides, the AD-loss exerts a pull effect, drawing feature representations towards a predefined central point. Conversely, for disease-positive bags that are primarily composed of negative tiles occasionally interspersed with positive ones, the AD-loss initiates a push-pull effect. Results on two histopathology datasets showcase our model's ability to boost classification performance by minimising false negatives.

Citation

2025

DOI

Source Title

Publisher

Institute of Cancer Research (University Of London)

ISSN

eISSN

Research Team

Dynamical Cell Systems

Notes