BACKGROUND: Serum prostate-specific antigen (PSA), when used in combination with existing detection methods, improves the clinician's ability to detect early and potentially curable prostate cancer. FINDINGS: This report describes clinically important issues about use of the serum PSA concentration for detecting early prostate cancer. Other PSA-related factors--PSA density, PSA velocity, and age-specific reference ranges--seem to enhance the ability of clinicians to distinguish benign prostatic conditions from early prostate cancer. Because digital rectal examination only minimally affects the serum PSA concentration, delaying a determination after this examination is unnecessary. Finasteride therapy for benign prostatic hyperplasia should be initiated only after the prostate has been evaluated for cancer because this 5 alpha-reductase inhibitor lowers the serum PSA value by approximately 50%; however, reassessment of the prostate for cancer is necessary if the PSA level fails to decrease as expected or increases to more than 2 ng/mL during finasteride treatment. CONCLUSION: Currently, PSA is the most important, accurate, and clinically useful tumor marker for prostate cancer.
BACKGROUND: Serum prostate-specific antigen (PSA), when used in combination with existing detection methods, improves the clinician's ability to detect early and potentially curable prostate cancer. FINDINGS: This report describes clinically important issues about use of the serum PSA concentration for detecting early prostate cancer. Other PSA-related factors--PSA density, PSA velocity, and age-specific reference ranges--seem to enhance the ability of clinicians to distinguish benign prostatic conditions from early prostate cancer. Because digital rectal examination only minimally affects the serum PSA concentration, delaying a determination after this examination is unnecessary. Finasteride therapy for benign prostatic hyperplasia should be initiated only after the prostate has been evaluated for cancer because this 5 alpha-reductase inhibitor lowers the serum PSA value by approximately 50%; however, reassessment of the prostate for cancer is necessary if the PSA level fails to decrease as expected or increases to more than 2 ng/mL during finasteride treatment. CONCLUSION: Currently, PSA is the most important, accurate, and clinically useful tumor marker for prostate cancer.