This is the Pytorch implementation for the multiple instance learning model described in the paper Dual-stream Multiple Instance Learning Network for Whole Slide Image Classification with Self-supervised Contrastive Learning.

Install anaconda/miniconda
Required packages

  $ conda env create --name dsmil --file env.yml
  $ conda activate dsmil

The MIL benchmark dataset can be downloaded via:

  $ python download.py --dataset=mil

Precomputed features for TCGA Lung Cancer dataset can be downloaded via:

  $ python download.py --dataset=tcga

This dataset requires 20GB of free disk space.

Train DSMIL on standard MIL benchmark dataset:

  $ python train_mil.py

Switch between MIL benchmark dataset, use option:

[--datasets]      # musk1, musk2, elephant, fox, tiger

Other options are available for learning rate (0.0002), cross validation fold (5), weight-decay (5e-3), and number of epochs (40).

Train DSMIL on TCGA Lung Cancer dataset (precomputed features):

 $ python train_tcga.py --simclr=0

If you are processing WSI from raw images, you will need to download the WSIs first.

1. Download WSIs.
   Navigate to './tcga-download/' and download WSIs from TCGA data portal using the manifest file and configuration file.
   The example shows the case of Windows operating system. The WSIs will be saved in './WSI/TCGA-lung/LUAD' and './WSI/TCGA-lung/LUSC'.
   The raw WSIs take about 1TB disc space and may take several days to download. Open command line tool (Command Prompt for the case of Windows), navigate to './tcga-download', and use commands:

  $ cd tcga-download
  $ gdc-client -m gdc_manifest.2020-09-06-TCGA-LUAD.txt --config config-LUAD.dtt
  $ gdc-client -m gdc_manifest.2020-09-06-TCGA-LUSC.txt --config config-LUSC.dtt

2. Prepare the patches.
   We will be using OpenSlide, a C library with a Python API that provides a simple interface to read WSI data. We refer the users to OpenSlide Python API document for the details of using this tool.
   The patches will be saved in './WSI/TCGA-lung/pyramid' in a pyramidal structure for the magnifications of 20x and 5x. Navigate to './tcga-download/OpenSlide/bin' and run the script 'TCGA-pre-crop.py'

  cd tcga-download/OpenSlide/bin
  $ python TCGA-pre-crop.py

3. Train the embedder.
   We provided a modified script from this repository Pytorch implementation of SimCLR For training the embedder.
   Navigate to './simclr' and edit the attributes in the configuration file 'config.yaml'. You will need to determine a batch size that fits your gpu(s). We recommand to use a batch size of at least 512 to get good simclr features. The trained model weights and loss log are saved in folder './simclr/runs'.

  cd simclr
  $ python run.py

4. Compute the features.

  $ python compute_feats.py

5. Start training.

  $ python train_tcga.py --simclr=1

You could modify train_tcga.py to easily let it work with your datasets. After you have trained your embedder, you will need to compute the features and organize them as:

1. For each bag, generate a .csv file where each row contains the feature of an instance. The .csv file should be named as "bagID.csv" and put into a folder named "dataset-name".

2. Generate a "dataset-name.csv" file with two columns where the first column contains the paths to all bagID.csv files, and the second column contains the bag labels.

3. Replace the corresponding file path in the script with the file path of "dataset.csv".

  bags_path = pd.read_csv(PATH_TO_[dataset-name.csv])

4. Configure the corresponding number of classes argument for creating the DSMIL model.
5. Start training.

  $ python train_tcga.py --simclr=1

If you use the code or results in your research, please use the following BibTeX entry.

@article{li2020dualstream,
  author =   {Bin Li and Yin Li and Kevin W. Eliceiri},
  title =    {Dual-stream Multiple Instance Learning Network for Whole Slide Image Classification with Self-supervised Contrastive Learning},
  journal =  {arXiv preprint arXiv:2011.08939},
  year =     {2020}
}