Surgeons in Japan have 3D printed out 10 different cancerous kidney models which can be used as a way for them to simulate complicated surgeries. Dr. Yoshiyuki Shiga lead the research for this procedure.
http://3dprint.com/2282/3d-print-can...-kidney-model/

Allowing surgeons to practice on an accurate, clear 3d model of the organ allows them to cut down the time that blood flow needs to be cut off from the patient's kidneys. This can lead to a much better prognosis, and a higher success rate for the patient's. Now we can say that 3d printed kidney, heart, and liver models have all been produced to help surgeons understand a procedure better. Here is a picture of one of the 3d printed polymer kidney models: