The concept of focal therapy is not new. Already in 1955 during the annual meeting of the Trans Southeast Section of the American Urological Association (AUA) a serie of partial prostatectomies has been presented by Dr R. Womack. At that time the delimitation of the prostatic tissue resection was empirical based on the macroscopic aspect and the consistency of the gland. With the onset of mpMRI and targeted biopsies more than half-century later some surgical teams have performed partial prostatectomies validating at the same time the focal approach in organ-confined prostate cancer . Meanwhile less invasive techniques have been developed for more than 20 years now using different kinds of energy. However it is the surge of the mpMRI and MRI/US software which has revolutionized the focal therapy field.
Vascular Targeted-Phototherapy (VTP) or Prostate Photodynamic Therapy or Tookad Prostate Therapy refers to the same non-thermal technique based on the use of a photosensitizer (Tookad) and a laser light. Amongst the focal therapy techniques used in localized prostate cancer the VTP is the sole to have reached the highest level of scientific evidence with a randomized clinical trial (RCT) 
This technology has been around for decades. Based on the use of an ultrasonic energy in the frequency range of 20 kHz–200 MHz to create focused thermal ablation of the targeted tissue this « cooking » strategy is performed at a temperature of 80 to 100° C 
In the oncology field cryotherapy has been used in different organs. In prostate cancer, the US seems to be the leading county for this technique which has been around for the last 20 years. Dr J.S. Jones with the COLD Registry has been studying one the oldest serie in the field.
Irreversible Electroporation Therapy is performed mainly using the Nanoknife® technology. Amongst the different technologies and energies it is the most recent. More and more teams through the world are evaluating this innovative approach.