PSAnivå

PSAnivå refers to the concentration of prostate-specific antigen (PSA) in the blood. PSA is a protein produced by cells of the prostate gland and can be measured in nanograms per milliliter (ng/mL). The test is used primarily in screening for prostate cancer, and in monitoring disease activity or response to treatment in men with known prostate cancer.

Interpretation of PSA results is not straightforward. A single PSA value does not prove cancer, and elevated levels can occur for several reasons other than cancer. Common factors that can raise PSA include aging, benign prostatic hyperplasia (BPH), prostatitis or urinary infection, recent ejaculation, prostate manipulation, or recent procedures. Conversely, a normal PSA does not guarantee absence of cancer, particularly in some men with aggressive disease.

Clinical use often involves considering age-specific ranges, PSA velocity (the rate of change over time), and sometimes additional tests. For example, the ratio of free to total PSA, PSA density (PSA relative to prostate volume), and imaging with MRI can help refine risk assessment. In many settings, a PSA level below about 4.0 ng/mL is considered normal, but this threshold is not universal and ranges can vary by age, race, and laboratory method.

Limitations and debates surround PSA screening, including risks of false positives and overdiagnosis. Decisions about testing and follow-up are typically made after discussion between a patient and clinician, taking individual risk factors, preferences, and the potential benefits and harms into account.