This study is designed to be a prospective, non-randomized pilot study in 6 subjects treated at up to three (3) clinical sites. This study will involve six (6) subjects who meet the low risk prostate cancer criteria defined by this protocol. The subjects' prostate cancer foci, the location of which will be determined by ultrasound guided transperineal 3-Dimensional Prostate Mapping Biopsy (3D-PMB), will be targeted for treatment with the NanoKnife System. The primary objective of this portion of the study will be to evaluate procedural and short-term post treatment safety of the NanoKnife treatment via incidence of adverse events and evaluation of effect on urologic (urinary and erectile) function. The secondary objective of this study is to evaluate the short term efficacy of the NanoKnife treatment. Local efficacy in the area of treatment will be assessed via histological evaluation of 3D-PMB cores obtained throughout the half of the prostate where treatment was targeted at three (3) months post NanoKnife treatment, to evaluate the ablation zone created by the NanoKnife treatment. Following the 3 month biopsy assessment the data from these 6 subjects will be submitted to FDA for confirmation of short term safety and efficacy.