Diagnosis of Prostate Cancer Screening by digital rectal examination (DRE) and prostate-specific antigen (PSA) Diagnosis by needle biopsy of the prostate (most common) or biopsy of metastatic lesion Grading by histology Staging by CT / MRI and bone scanning, possibly prostate-specific membrane antigen (PSMA) - based PET CT Sometimes stony-hard induration or nodules are palpable during DRE, but the examination is often normal; induration and nodularity suggest cancer but must be differentiated from granulomatous prostatitis, prostate calculi, and other prostate disorders.