Detecting skin cancer with an iPhone Tory Jarmain CEO & - - PowerPoint PPT Presentation
Detecting skin cancer with an iPhone Tory Jarmain CEO & - - PowerPoint PPT Presentation
Detecting skin cancer with an iPhone Tory Jarmain CEO & Co-Founder Skin disorders are prevalent in 43% of outpatient visits Source: Why do patients visit their doctors? Assessing the most prevalent conditions in a defined US
Skin disorders are prevalent in 43% of outpatient visits
Source: “Why do patients visit their doctors? Assessing the most prevalent conditions in a defined US population.“ Stauver, et al.
PREVALENCE DISEASE GROUP 0-18 19-29 30-49 50-64 65+ All Skin disorders 33% 38% 41% 50% 66% 43% Arthritis and joint disorders 14% 25% 35% 50% 63% 34% Back problems 6% 20% 29% 34% 44% 24% Lipid metabolism disorders 0% 3% 19% 49% 70% 22% Upper respiratory disease 24% 19% 22% 22% 23% 22%
Source: “Why do patients visit their doctors? Assessing the most prevalent conditions in a defined US population.“ Stauver, et al.
Source: American Academy of Dermatology
1 in 5 Americans will develop skin cancer in their lifetime
Source: American Academy of Dermatology
1 in 3 cancer diagnoses is skin cancer
Source: “Deep Networks for Early Stage Skin Disease and Skin Cancer Classification.” Esteva, et al.
Dermatologists have 52% accuracy classifying skin lesions with non-dermoscopic imagery
MELANOMA BENIGN
Source: American Academy of Dermatology
The average wait time to see a dermatologist is 1 month in the U.S. and 3-6 months in much of the world. In that time, skin disorders can become life threatening.
Source: Merritt Hawkins
Use deep learning to triage skin disorder cases OUR IDEA
Snap a photo, detect a skin disorder and see visually similar cases SOLUTION
View results Learn more Snap a photo
D
MELANOMA DETECTION
Assist physicians in binary classification of skin lesions SCOPE
Achieve or improve upon state-of-the-art results for skin lesion segmentation and classification. Measure the impact of segmentation on the accuracy of the classifier.
GOALS
Segmenting skin lesions improves the accuracy and sensitivity
- f a deep learning
classification model
HYPOTHESIS
Dermoscopic images may contain artifacts, be low contrast, and contain multiple lesions CHALLENGES
CONVOLUTIONAL NEURAL NETWORKS
CONVOLUTION LAYER
Source: “Deep Learning for Computer Vision.” Karpathy, Andrej.
CONVOLUTION LAYER
Source: “Deep Learning for Computer Vision.” Karpathy, Andrej.
CONVOLUTION LAYER
Source: “Deep Learning for Computer Vision.” Karpathy, Andrej.
ACTIVATION LAYER
Source: “Skin Lesion Detection From Dermoscopic Images Using Convolutional Neural Networks”
POOLING LAYER
Source: “Deep Learning for Computer Vision.” Karpathy, Andrej.
FULLY CONNECTED LAYER
Source: “Deep Learning for Computer Vision.” Karpathy, Andrej.
MAIN SCHEME
Source: LeCun, et al.
MAIN SCHEME
Source: LeCun, et al.
MAIN SCHEME
Source: LeCun, et al.
MAIN SCHEME
Source: LeCun, et al.
Class Benign Malignant Total Training subset 727 173 900 Test subset 304 75 379
DATA AUGMENTATION
Original image
Random transformations
METHOD SCHEME
Source: “Convolutional Networks for Biomedical Image Segmentation.” Olaf Ronneberger, et al. Original skin lesion Binary mask
SEGMENTATION
CLASSIFICATION WITH VGG-16
- Five convolutional blocks
- 3 x 3 receptive field
- ReLU as Activation Function
- Max-Pooling
- Classifier block
- 3 fully-connected layers at
the top of the network
Pretrain a ConvNet on a very large dataset (e.g. ImageNet, which contains 1.2 million images with 1000 categories), and then use the ConvNet either as an initialization or a fixed feature extractor for the task of interest.
TRANSFER LEARNING
Train this Freeze these
EVALUATION
SEGMENTATION EVALUATION
Rank Participant Jaccard Index Dice Coefficient Accuracy Sensitivity Specificity 1 Adrià Romero Lopez 0.918 0.869 0.918 0.930 0.954 1 Urko Sanchez 0.843 0.910 0.953 0.910 0.965 2 Lequan Yu 0.829 0.897 0.949 0.911 0.957 3 Mahmudur Rahman 0.822 0.895 0.952 0.880 0.969 Ground truth Mask obtained 1 MIDDLE Group
1
CLASSIFICATION EVALUATION
Model Accuracy Loss Sensitivity Precision Unaltered lesion classifier 0.847 0.472 0.824 0.952 Perfectly segmented lesion classifier 0.840 0.496 0.865 0.962 Automatically segmented lesion classifier 0.817 0.514 0.892 0.968
CLASSIFICATION EVALUATION
Model Accuracy Loss Sensitivity Precision Unaltered lesion classifier 0.847 0.472 0.824 0.952 Perfectly segmented lesion classifier 0.840 0.496 0.865 0.962 Automatically segmented lesion classifier 0.817 0.514 0.892 0.968
CLASSIFICATION EVALUATION
With segmentation
- Accuracy decreases
- Loss increases
Model Accuracy Loss Sensitivity Precision Unaltered lesion classifier 0.847 0.472 0.824 0.952 Perfectly segmented lesion classifier 0.840 0.496 0.865 0.962 Automatically segmented lesion classifier 0.817 0.514 0.892 0.968
CLASSIFICATION EVALUATION
With segmentation
- Sensitivity increases
- Precision increases
SENSITIVITY
The most important metric in medical settings. By missing a true melanoma case (False Negative) the model would fail in early
- diagnosis. It is better to raise a False Positive
than to create a False Negative.
SENSITIVITY
number of true positives number of true positives + number of false negatives Sensitivity =
Model Accuracy Loss Sensitivity Precision Unaltered lesion classifier 0.847 0.472 0.824 0.952 Perfectly segmented lesion classifier 0.840 0.496 0.865 0.962 Automatically segmented lesion classifier 0.817 0.514 0.892 0.968
CLASSIFICATION EVALUATION
The automatically segmented classifier performs best
CONFUSION MATRICES
Unaltered Classifier
Perfectly Segmented Classifier
Automatically Segmented Classifier
False Negatives descending
23-WAY CLASSIFICATION
23,000 images 600 diseases
Sources: “A Deep Learning Approach to Universal Skin Disease Classification.” Liao, Haofu. “Deep Networks for Early Stage Skin Disease and Skin Cancer Classification.“ Esteva, et al.
- Acne and rosacea
- Malignant lesions
- Atopic dermatitis
- Bullous disease
- Bacterial infections
- Eczema
- Exanthems & drug eruptions
- Hair diseases
- STDs
- Pigmentation disorders
- Connective tissue diseases
- Melanoma, nevi & moles
- Nail diseases
- Contact dermatitis
- Psoriasis & lichen planus
- Infestations & bites
- Benign tumors
- Systemic disease
- Fungal infections
- Urticaria
- Vascular tumors
- Vasculitis
- Viral infections
Deep Residual Networks
Source: “Deep Residual Networks: Deep Learning Gets Way Deeper.” He, Kaiming.
Source: “Deep Residual Networks: Deep Learning Gets Way Deeper.” He, Kaiming.
Source: “Deep Residual Networks: Deep Learning Gets Way Deeper.” He, Kaiming.
Source: “Deep Residual Learning for Image Recognition.” Kaiming, et al.