The clinical application of a Prostate Mechanical Imaging (PMI) technique for prostate assessment is examined in this study. PMI technology is based on the visualization of internal structures and dimensions of the prostate by measuring mechanical stress patterns on the gland surface with pressure sensor arrays. Temporal and spatial changes in the stress pattern provide information on the hardness of the prostate. Projected patient sample size for the study is 40 men over the age of 21. Patients will be selected for the study if both of the following criteria are met: (1) abnormal DRE findings; and (2) patients who are scheduled for a TRUS-guided prostate biopsy and/ or radical prostatectomy due to an abnormal DRE, and/or increased PSA, and/or other clinical indications.