Test Catalog

Test Id : PACP

Prostatic Acid Phosphatase, Serum

Useful For
Suggests clinical disorders or settings where the test may be helpful

Aiding in predicting recurrence after radical prostatectomy for clinically localized prostate cancer


Following response to androgen ablation therapy, when used in conjunction with prostate-specific antigen

Method Name
A short description of the method used to perform the test

Automated Chemiluminescent Immunometric Assay

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Prostatic Acid Phosphatase, S

Lists additional common names for a test, as an aid in searching

Acid Phosphatase, Prostatic Isoenzyme, ELISA

PAP, Prostatic Acid Phosphatase


Specimen Type
Describes the specimen type validated for testing


Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Patient Preparation: For 12 hours before specimen collection, do not take multivitamins or dietary supplements containing biotin (vitamin B7), which is commonly found in hair, skin, and nail supplements and multivitamins.

Collection Container/Tube: 

Preferred: Red top

Acceptable: Serum gel

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

0.4 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject
Gross lipemia OK

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 7 days
Frozen 180 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Aiding in predicting recurrence after radical prostatectomy for clinically localized prostate cancer


Following response to androgen ablation therapy, when used in conjunction with prostate-specific antigen

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Prostatic acid phosphatase (PAP), a glycoprotein synthesized by the prostate gland, is a member of a diverse group of isoenzymes that are capable of hydrolyzing phosphate esters in acidic medium. They are classified on the basis of their electrophoretic mobilities.


PAP was a major tumor marker for prostate cancer for more than 50 years.(1) However, PAP is no longer used to screen for or stage prostate cancer. In most instances, serum prostate specific antigen (PSA) is used instead. PAP usefulness is now limited to niche applications. Pre-treatment PAP measurement may add unique, clinically useful prognostic information for predicting recurrence in men who are undergoing radical prostatectomy for clinically localized prostate cancer. PAP also may be useful for following the progression of disease response to therapy in men treated by androgen ablation. However, for both of these applications, PSA provides more information and also should be utilized.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

< or =2.1 ng/mL

Provides information to assist in interpretation of the test results

Prostatic acid phosphatase (PAP) levels above the reference range may indicate prostate cancer, but can be due to many other factors, see Cautions.


A rise in PAP levels in patients with known prostate cancer can indicate tumor progression or recurrence. However, there is considerable intra-subject biological variability, limiting the usefulness of this test.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Prostatic acid phosphatase (PAP) measurement must not be regarded as an absolute test for malignancy since other factors, including benign prostatic hyperplasia, prostatic infarction, and manipulation of the prostate gland may result in elevated serum PAP concentrations.


PAP measurements provide little additional information beyond that provided by prostate-specific antigen measurements.


Human anti-mouse antibodies (HAMA) may be present in specimens from patients who have received immunotherapy utilizing monoclonal antibodies. Other heterophile antibodies also may be present in patient specimens. This assay has been specifically formulated to minimize the effects of these antibodies on the assay. However, carefully evaluate results from patients known to have such antibodies.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Moul JW, Connelly RR, Perahia B, McLeod DG: The contemporary value of pretreatment prostatic acid phosphatase to predict pathological stage and recurrence in radical prostatectomy cases. J Urol. 1998;159:935-940

2. Beaver TR, Schultz AL, Fink LM, et al: Discordance between concentration of prostate-specific antigen and acid phosphatase in serum of patients with adenocarcinoma of the prostate. Clin Chem. 1988;34:1524

3. Velonas VM, Woo HH, dos Remedios CG, Assinder SJ: Current status of biomarkers for prostate cancer. Int J Mol Sci. 2013 May 24;14(6):11034-60. doi: 10.3390/ijms140611034

4. Kong HY, Byun J: Emerging roles of human prostatic Acid phosphatase. Biomol Ther (Seoul). 2013 Jan;21(1):10-20. doi: 10.4062/biomolther.2012.095

Method Description
Describes how the test is performed and provides a method-specific reference

The patient sample is added to a solid phase that is coated with a mouse monoclonal antibody specific for prostatic acid phosphatase (PAP). A goat-anti-PAP-alkaline phosphatase conjugate is added to form an antibody sandwich complex. Excess conjugate is removed by washing and an adamantyl dioxetane phosphate substrate is added to produce chemiluminescence. Light emission is proportional to PAP concentration in the specimen.(Package insert: IMMULITE 2000 PAP. PIL2KPA-17. Siemens Healthcare; 03/15/2018)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday, Wednesday, Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

1 to 3 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

3 months

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

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Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.


LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
PACP Prostatic Acid Phosphatase, S 20420-6
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
PACP Prostatic Acid Phosphatase, S 20420-6

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports