Final answer:
The primary screening modality for prostate cancer is Prostate specific antigen (PSA).
Step-by-step explanation:
A routine exam by a doctor may find a lump on the prostate, which might be followed by a blood test that detects an elevated level of PSA. PSA is a protein secreted by the prostate that normally circulates in the blood. Higher-than-normal levels of PSA can be caused by prostate cancer, but they may also have other causes. Ultrasound or magnetic resonance imaging (MRI) might also be undertaken to provide images of the prostate gland and additional information about cancer.