return to P index

return to index page

PTD-285

Test Directory - Prostate Specific Antigen (PSA)

The PSA method will be changing from 4th October 2016. Due to differences between the new and old method PSA will be reported with two values to enable the establishment of a new PSA baseline for monitoring purposes. Values obtained from other laboratories with different assay methods cannot be used interchangeably.

Synonyms

PSA

Clinical Indications

In combination with digital rectal examination PSA can aid diagnosis of prostate cancer in symptomatic patients. PSA is also useful for monitoring patients with diagnosed pancreatic cancer. The value of PSA in screening asymptomatic men has not been proven in clinical trials.

Request Form

Combined Pathology Blood form (Yellow/Black)

Availability

On request

Specific Criteria

Should not be used for screening in asymptomatic men. A patient information leaflet is available

Patient Preparation

Urological manipulations affect PSA levels and if possible sample should be taken before procedure. Effects are as follows:

DRE / 
Prostate massage

May cause minor increases in some patients, take sample for PSA before procedure.

Ejaculation

Results conflicting but may increase PSA levels.

TURP / 
Needle Biopsy

Increases PSA levels significantly. Wait at least 6 weeks before taking sample for PSA levels 

Ultrasound

Increases PSA levels in a minority of patients

Cystoscopy

Flexible cystoscopy does not appear to increase PSA levels but rigid cystoscopy may increase levels.

Turnaround Time

Same Day

Specimen

Serum

Volume

2 ml

Container

Yellow top (SST) tube or

Paediatric orange top (lithium-heparin)

Reference Range

In line with the UKNSC Screening for Prostate Cancer Review (2015) the following referral cut offs are reported:

Age (M)

Threshold:

≤69 yr     

<3 ng/ml

70-79 yr    

<5 ng/ml

≥80 yr     

No range

    

Half-life in Serum

Approx. 2.5 days after radical prostatectomy. Half-life after radiotherapy may be many months.

Interpretation

Benign prostatic hypertrophy (BPH), acute and chronic prostatitis, urinary retention, prostate biopsy, prostate massage and ejaculation may give rise to transient elevation of PSA levels

Lab handling

 

Processing: Analysed from primary tube at the Hub laboratory and stored at 4C


 Version 2.1 / Jan 2017                                                                                                          Approved by: Consultant Biochemist