PROSABI: Prospective Multi-centre Study of Prognostic Factors in mCRPC Patients Treated With Abiraterone Acetate.

Inclusion Criteria: 1. Male age ≥ 18 years 2. Histologically confirmed adenocarcinome of the prostate 3. ECOG Performance Status ≤ 2 4. Castration resistance must be documented with surgical or medical castration with serum testosterone \< 50 ng/mL (\< 2.0 nM). 5. Men diagnosed with at least one metastatic lesion on CT or bone scan. 6. Documented biochemical and/or radiographic progression to previous treatment according to PCWG2 criteria. 7. Patients who are candidates for standard of care treatment with abiraterone acetate: 1000 mg every 24 hours plus prednisone 5 mg every 12 hours. 8. Availability of formalin-fixed paraffin-embedded blocks from the prostate biopsy and/or radical prostatectomy. 9. Acceptable hematological, hepatic and renal functions.9. Acceptable haematological, hepatic and renal functions. Exclusion Criteria: 1. Previous cancer diagnosis, except those patients who had a localized malignant tumour and who are five years cancer-free or those diagnosed with skin cancers (of non-melanoma type) or excised in situ carcinomas. 2. Any condition or reason that, in the opinion of the Investigator, interferes with the ability of the patient to participate in the trial, which places the patient at undue risk, or complicates the interpretation of safety data