Mp-3TMRI and 68Ga-PSMA PET/CT Guided Prostate Biopsy and Tumor Node Metastasis (TNM) Staging.

Inclusion Criteria: Cohort 1 - Biopsy guidance in clinically-suspected PCa 1\. Men aged 45 to 75 years old with clinically-suspected PCa candidated for either initial or repeat TRUS-guided prostate biopsy, meeting any of the following criteria: a) Abnormal PSA metrics, defined as follows: A rising and/or persistently elevated serum PSA (i.e PSA \> 2.5ng/ml for men in the age group comprising 60 to 75 years old; PSA \> 3.0ng/ml for men in the age group comprising 45 to 60 years old) and at least one of the following PSA-based metrics: i. Percent free PSA (%fPSA) \< 25% with PSA range 4-10ng/ml (NCCN); ii. PSA velocity (PSAvel) \>0.35 ng/mL/y; iii. PSA density (PSAden) \> 0.25ng/mL/cc iv. PSA \> 10ng/ml, 50% risk of PCa (EAU) b) Suspicious digital rectal examination (DRE), 5-30% risk of PCa; c) Prostate Cancer Gene 3 (PCA3) \> 35; d) Suspicious findings on first-round biopsy: i. A few Atypical Glands immediately adjacent to HG-PIN, 50% risk of PCa; ii. Atypical Small Acinar Proliferation, 40% of PCa; iii. Multifocal High-Grade Prostatic intraepithelial neoplasia (HG-PIN), 30% ; iv. Intraductal carcinoma as solitary finding, 90% of PCa; Cohort 2 - Biopsy guidance on Active Surveillance Men consenting to enter the PRIAS MRI side-study as per currently inclusion criteria in Version Number 1.0 dated August 20, 2013. These are: 1. Histologically-proven adenocarcinoma of the prostate; 2. Age ≥ 18 3. Men should be fit for curative treatment; 4. Clinical stage T1c or T2; 5. Gleason score 3+3=6; 6. One or two biopsy cores invaded with prostate cancer: 1. If an MRI, including targeted biopsies on positive lesions, is done at inclusion, there is no limit in the number of positive cores (that is, more than two, and no limit in the % of cancer present in the cores); 2. If saturation biopsies (either trans-perineal or trans-rectal) are done 15% of the cores can be positive with a maximum of 4 (i.e. 26 cores 4 cores can be positive) (all other inclusion criteria still apply); 7. PSA density (PSA D) less than 0.2; 8. PSA-level at diagnosis ≤ 10 ng/mL; Cohort 3a - Pre-surgical TNM staging in high-risk prostate cancer 1. Male, aged 18 years or older; 2. Cyto / histological confirmation of PCa (i.e. TRUS-guided biopsies; TURP); 3. Any of the PCa high risk features for Organ-Confined Disease (OCD): * Clinical T stage ≥ T2c; * Gleason Score ≥ 8; * Serum PSA \> 20 ng/mL; 4. Any of the PCa high-risk features for Locally-Advanced Disease (LAD): * Clinical T stage ≥ T3b-T4 OR any T and clinical N1 disease; * Gleason Score ≥ 8; * Serum PSA \> 20 ng/mL; 5. Routine clinical staging (CTscan ± Bone scan) performed within 12 weeks enrolment returning negative or equivocal results for distant metastatic disease; Cohort 3b - pelvic TNM staging of prostate cancer prior to nerve-sparing radical prostatectomy 1. Male, aged 18 years or older; 2. Cyto / histological confirmation of PCa (i.e. TRUS-guided biopsies; TURP); 3. All of the following PCa-related features must be met for nerve-sparing (either mono- or bi-lateral): * Clinical T stage ≤ T2b; * Gleason Score ≤ 7 (3+4) and maximum one biopsy with Gleason \> 6 at the ipsilateral side; * Serum PSA \< 10 ng/mL; Exclusion Criteria: The participant may not enter the study if ANY of the following apply: 1. Hormone androgen deprivation therapy of any type within 6 months prior to enrollment. 2. Prior pelvic radiotherapy; 3. Sickle cell disease; 4. Insufficient renal function (eGFR \< 30 mL/min/1.73 m2); 5. Hip prosthesis, vascular grafting or other conditions affecting imaging; 6. Contraindication to MRI, including but not restricted to: pacemaker or other electronic im-plants, known metal in the orbit, MR incompatible surgical or cerebral aneurysm clips, shrapnel, tattoos, non-removable body piercings (relative contraindications); 7. History of allergic reactions attributed to compounds of similar chemical or biologic com-position to 68Ga-PSMA or Gadolinium-based contrast agents used in the study.