How do you know if someone has prostate cancer?

Prostate cancer dx: Only men get prostate cancer (women don't have prostates). To diagnose this, men usually first are found to have a high result on a blood test called the PSA. This can also be high for other reasons, so to see if it is from cancer, they undergo a biopsy done by a urologist (doctor specializing in male urinary tract). Biopsy is done in the office as outpatient.