ImageNet has 1,034,908 labeled images. In a hospital setting, you'd be lucky to get 1000 participants.
That means those datasets really show off the power of unsupervised, semi-supervised, or one-shot learning algorithms. And if you set up the problem well, each increment of ROC translates into a life saved.
Happy to point you in the right direction when the time comes—my email is in my HN profile.