Computational Pathology

Report on Current Developments in Computational Pathology

General Trends and Innovations

The field of computational pathology is witnessing significant advancements, particularly in the areas of image translation, tumor classification, prognostic prediction, and cell layout generation. These developments are driven by the integration of deep learning techniques, multiple instance learning (MIL), and generative models, which are enhancing the accuracy and efficiency of diagnostic and prognostic tasks.

  1. Image Translation and Staining Conversion: There is a growing focus on converting Hematoxylin and Eosin (H&E) stained images to Immunohistochemistry (IHC) stained images, which is crucial for cost-effective and efficient diagnostic processes. Recent innovations in this area leverage the shared Hematoxylin channel between H&E and IHC staining, coupled with advanced loss functions tailored for specific staining channels. This approach not only improves the quality of translated images but also introduces novel metrics for assessing semantic information, such as HER2 levels in breast cancer diagnostics.

  2. Tumor Classification and Multi-Center Generalization: The classification of pediatric brain tumors using digital histopathology and deep learning is advancing, with a particular emphasis on weakly supervised multiple-instance learning (MIL) approaches. These methods, which aggregate patch-level features from state-of-the-art histology-specific foundation models, are showing promising results in multi-center cohorts. The ability to generalize across different centers is a notable achievement, indicating the potential for widespread application in pediatric brain tumor diagnostics.

  3. Prognostic Prediction and Time to Recurrence: Predicting time to biochemical recurrence in prostate cancer is being approached through innovative two-stage MIL strategies. These methods first identify the most relevant areas in whole slide images (WSIs) and then use higher resolution patches to predict recurrence times. The approach demonstrates strong performance in both internal validation and external challenge datasets, with attention visualization providing insights into the most critical areas for prediction.

  4. Cell Layout Generation and Spatial Patterns: Generative models, particularly diffusion models, are being adapted for cell detection tasks in pathology images. A novel approach focuses on generating realistic cell layouts by incorporating spatial patterns, which has been shown to significantly boost the performance of state-of-the-art cell detection methods. This innovation underscores the importance of spatial information in pathology image analysis and opens new avenues for data augmentation and model performance enhancement.

  5. Cell Instance Segmentation and Classification: Advances in cell instance segmentation and classification are being driven by deep learning frameworks that can handle complex tissue types and diverse staining techniques. These methods, which often feature lightweight U-Net architectures with multiple heads, are capable of segmenting and classifying cells with high accuracy and robustness. The introduction of new datasets, such as Nissl-stained images, further supports the development and validation of these techniques.

Noteworthy Papers

  • DeReStainer: Introduces a destain-restain framework for converting H&E to IHC staining, with innovative loss functions and semantic information metrics for HER2 levels.
  • Pediatric brain tumor classification: Demonstrates the potential of weakly supervised MIL approaches in multi-center pediatric brain tumor classification, with strong generalization across different centers.
  • Biochemical Prostate Cancer Recurrence Prediction: Proposes a two-stage MIL strategy for predicting time to recurrence, with attention visualization highlighting critical areas for prediction.
  • Spatial Diffusion for Cell Layout Generation: Focuses on generating realistic cell layouts using spatial patterns, significantly boosting cell detection performance.
  • CISCA and CytoDArk0: Introduces a deep learning framework for cell instance segmentation and classification, supported by a new Nissl-stained dataset for brain cytoarchitecture studies.

These papers represent significant strides in computational pathology, offering innovative solutions and advancing the field in multiple dimensions.

Sources

DeReStainer: H&E to IHC Pathological Image Translation via Decoupled Staining Channels

Pediatric brain tumor classification using digital histopathology and deep learning: evaluation of SOTA methods on a multi-center Swedish cohort

Biochemical Prostate Cancer Recurrence Prediction: Thinking Fast & Slow

Spatial Diffusion for Cell Layout Generation

CISCA and CytoDArk0: a Cell Instance Segmentation and Classification method for histo(patho)logical image Analyses and a new, open, Nissl-stained dataset for brain cytoarchitecture studies