Prostate-specific antigen (PSA) is a glycoprotein found in the prostate tissues. Its presence is tested by immunoassay techniques to assist in the detection of prostatic carcinoma. It is considered to be a more specific immunohistochemical marker for metastatic tumor of prostate origin than is ACP. ACP is a test also performed to diagnose prostatic carcinoma, but it is not entirely specific for this disease, because increased values have been noted in bladder as well as in prostatic carcinoma. Increased levels of PSA correlate with the amount of prostatic tissue, both malignant and benign.

• Prostatic massage or rectal examination within 48 hours of the test can cause elevated levels.

• Screening for early detection of prostate carcinoma and evaluating those who are at risk for this disease, primarily men over 40 years of age
• Diagnosing a malignant tumor of the prostate gland, revealed by increased levels, depending on the volume of the tumor
• Determining chemotherapeutic regimen protocol or radiation therapy and monitoring and evaluating the response to therapy, revealed by a decrease in the PSA level
• Evaluating progression or recurrence of the tumor, revealed by a rise in the PSA level

Nursing Care Before the Procedure

Client preparation is the same as that for any test involving the collection of a peripheral blood sample (see Appendix I).

A venipuncture is performed and the sample collected in a red-topped tube. The age of the client should be noted on the laboratory form. The sample should be refrigerated if the test is not performed within 24 hours.

Nursing Care After the Procedure

Care and assessment after the procedure are the same as for any study involving the collection of a peripheral blood sample.