Prostate Specific Antigen (PSA) - Free and Total, Serum/Plasma

Test Overview

Method

Electrochemiluminescent immunoassay (ECLIA)

Result Included

Total PSA; Free PSA; Free PSA/Total PSA Ratio

Specimen

Specimen Type

Serum
Plasma (Li Heparin)
Plasma (EDTA)

Volume

Sample Volume

2 mL

Specimen Comment

Barricor™ tube is not acceptable.

Collection & Handling

Collection Instructions

Recommend collecting prior to rectal exam or other action that may alter circulating PSA concentration.

Handling Information

Store and send frozen.

Stability

Refrigerated	Frozen
5 days	3 months

Rejection Criteria

Criteria	Specification
Specimen	Barricor™ tube

Performance & Interpretation

Turnaround Time

2 days

Results

PSA - Total

µg/L

Less than 4.0
May be increased by prostate manipulation (massage/biopsy) or cytoscopy. Hospitalization may decrease PSA levels.

ng/mL x 1.00
Free PSA

µg/L

See interpretation for Free/Total PSA Ratio.

ng/mL x 1.00
Free PSA/Total PSA Ratio

Ratio

Total <4: Prostate cancer unlikely and Free is not informative.
Total ≥10: Prostate cancer likely and Free is not informative.
Total ≥4 and ≤10: If Free/Total ratio ≥0.27, chance of prostate cancer is about 10%. If ratio is <0.17, chance of prostate cancer is about 50%.

Referral Location

Canada

Interface & Setup

HL7 Interface Codes

Order Code	Result Name	Result Codes	Units
FPSA	Prostate Spec Ag (Monitor)	20696	ug/L
	Free PSA (Monitor)	20697	ug/L
	Free/Total PSA Ratio	20698

Test Version

Last Updated

2023-02-01

Prostate Specific Antigen (PSA) – Free and Total, Serum/Plasma