Acid phosphatase

Specimen:

5 mL blood in lithium heparin or plain tube. May require early separation into tube with special preservatives.

Defer collection for at least 72 h after rectal examination, urethral instrumentation, prostatic massage or FNAB, as high levels may result from these procedures.

Method:

Immunoassay, spectrophotometry.

Reference Interval:

Method dependent - consult pathologist.

Application:

Test largely superseded by Prostate specific antigen assay, which has greater sensitivity and specificity for the detection of invasive or metastatic adenocarcinoma of the prostate.

May be useful in monitoring Gaucher disease.

Interpretation:

The test is relatively specific for the prostatic isoenzyme. High levels indicate tumour extension beyond the prostatic capsule or metastatic spread. A normal level does not exclude the diagnosis of prostatic malignancy.

The preferred test is Prostate specific antigen.

Reference:

Gao X et al. Prostate 1997; 31: 264-281.