Prostate Cancer Screening

Screening looks for prostate cancer in a person without symptoms; it is not the same activity as investigating urinary complaints, monitoring a known cancer, or checking response after treatment. The main screening test is serum prostate-specific antigen (PSA), a protein produced by prostate tissue. PSA is prostate-specific, not cancer-specific: malignant cells may increase PSA leakage into the blood, but benign prostatic hyperplasia, prostatitis, urinary infection, recent ejaculation, and recent prostate instrumentation can do the same. Most prostate cancers found through screening are asymptomatic. Hesitancy, weak stream, and nocturia more often reflect benign prostatic hyperplasia than cancer, while the absence of urinary symptoms does not make cancer impossible. Screening therefore begins with a decision about whether testing is likely to offer meaningful benefit, not with a search for symptoms. The benefit is earlier detection of clinically significant disease. The cost is a chain of possible downstream harm: an elevated result can lead to repeat testing, MRI, biopsy, and treatment for a cancer that would never have caused illness. Treatment may cause erectile dysfunction, urinary incontinence, or infection. The person must understand...