Prostate specific antigen (PSA) is currently the primary screening tool for prostate cancer, but PSA values can be affected by numerous factors.
For example, the results may vary slightly from test to test, depending on the standard of the instrument and the reagents used. Some drugs can affect PSA values, such as 5α-reductase inhibitors, and it is important to inform your doctor before the test.
In addition, rectal examinations, prostate massage, cystoscopy, catheterization, transrectal ultrasonography, prostate puncture, acute urinary retention, severe constipation, and ejaculation can also cause a transient increase in PSA values. Other diseases of the prostate, such as acute prostatitis and prostate enlargement, can also cause an abnormal increase in PSA values.
Take care to exclude these factors when performing PSA testing to get the most accurate PSA values possible.