lungCT

Second Prize Julian's Blog

First Prize Liao Fangzhou

Related Blog: https://www.jianshu.com/p/50158f8daf0d and https://blog.csdn.net/qq_25624231/article/details/79632072

Goal

To predict the development of lung cancer in a patient given a set of CT images.

Solution

To spoonfeed a neural network with examples with a better snr and a more direct relationship between the labels and the features.

• Train a network to detect nodules and predict the malignancy of detected nodules.
• Estimate the chance that the patient would develop a cancer given this information and some other features.

Papers

U-Net:Convolutional Networks for Biomedical Image Segmentation

Multi-region two-stream R-CNN for a action detection

Evaluate the Malignancy of Pulmonary Nodules Using the 3D Deep Leaky Noisy-or Network

1. Preprocessing

step1_preprocess_ndsb.py This will extract all the ndsb dicom files , scale to 1x1x1 mm, and make a directory containing .png slice images. Lung segmentation mask images are also generated. They will be used later in the process for faster predicting.

step1_preprocess_luna16.py This will extract all the LUNA source files , scale to 1x1x1 mm, and make a directory containing .png slice images. Lung segmentation mask images are also generated. This step also generates various CSV files for positive and negative examples.

step1b_preprocess_make_train_cubes.py The nodule detectors are trained on positive and negative 3d cubes which must be generated from the LUNA16 and NDSB datasets. step1b_preprocess_make_train_cubes.py takes the different csv files and cuts out 3d cubes from the patient slices. The cubes are saved in different directories.

resources/step1_preprocess_mass_segmenter.py generate the mass u-net trainset. The generated resized images + labels is provided in this archive so this step does not need to be run. However, this file can be used to regenerate the traindata.

2. Training neural nets

step2_train_nodule_detector.py train the 3D convnets that detect nodules and predict malignancy.T his will train various combinations of positive and negative labels. The resulting models (NAMES) are stored in the ./workdir directory and the final results are copied to the models folder.

step2_train_mass_segmenter.py train the mass detector. It trains 3 folds and final models are stored in the models (names) folder. Training the 3D convnets will be around 10 hours per piece. The 3 mass detector folds will take around 8 hours in total.

3. Predicting neural nets

step3_predict_nodules.py detect nodules in a 3d grid per patient. The detected nodules and predicted malignancy are stored per patient in a separate directory.

4. Training of submissions, combining submissions

step4_train_submissions.py Based on the per-patient csv’s the masses.csv and other metadata we will train an xgboost model to generate submissions.

There are 3 levels of submissions. First the per-model submissions. (level1). Different models are combined in level2, and Daniel’s submissions are added. These level 2 submissions will be combined (averaged) into one final submission. Below are the different models that will be generated/combined.

Level 1
Luna16_fs (trained on full luna16 set)
Luna16_ndsbposneg v1 (trained on luna16 + manual pos/neg labels in ndsb)
Luna16_ndsbposneg v2 (trained on luna16 + manual pos/neg labels in ndsb)
Daniel model 1
Daniel model 2
posneg, daniel will be averaged into one level 2 model

Level 2
Luna16_fs
Luna16_ndsbposneg
Daniel

These 3 models will be averaged into 1 final_submission.csv

数据集

训练集由LUNA16数据集（the Lung Nodule Analysis 2016）和NDSB3（Data Science Bowl 2017）数据集两部分组成. LUNA16 888个病例，标记了1186个肺结节； NDSB3: 1397 train，198 validate，506 test，且人工标注了训练集中754个结节和验证集中78个结节。

LUNA16存在许多较小注释结节，且临床经验认为直径6mm以下的肺结节无危险。但NDSB3数据集中，存在较多的大直径结节且结节多与主支气管相连。因此，针对两个数据集的差异，需去除LUNA16数据集中直径6mm的结节，同时对NDSB3数据集进行人工标注。

Progress

• Mon-Aug 20, read web information
• Tue, read blog, download related papers, clear about the outline of this problem.
• Wed, ....